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Sample records for particle physics quantum

  1. Exceptional quantum geometry and particle physics

    NASA Astrophysics Data System (ADS)

    Dubois-Violette, Michel

    2016-11-01

    Based on an interpretation of the quark-lepton symmetry in terms of the unimodularity of the color group SU (3) and on the existence of 3 generations, we develop an argumentation suggesting that the "finite quantum space" corresponding to the exceptional real Jordan algebra of dimension 27 (the Euclidean Albert algebra) is relevant for the description of internal spaces in the theory of particles. In particular, the triality which corresponds to the 3 off-diagonal octonionic elements of the exceptional algebra is associated to the 3 generations of the Standard Model while the representation of the octonions as a complex 4-dimensional space C ⊕C3 is associated to the quark-lepton symmetry (one complex for the lepton and 3 for the corresponding quark). More generally it is suggested that the replacement of the algebra of real functions on spacetime by the algebra of functions on spacetime with values in a finite-dimensional Euclidean Jordan algebra which plays the role of "the algebra of real functions" on the corresponding almost classical quantum spacetime is relevant in particle physics. This leads us to study the theory of Jordan modules and to develop the differential calculus over Jordan algebras (i.e. to introduce the appropriate notion of differential forms). We formulate the corresponding definition of connections on Jordan modules.

  2. Quantum Optics, Diffraction Theory, and Elementary Particle Physics

    ScienceCinema

    None

    2016-07-12

    Physical optics has expanded greatly in recent years. Though it remains part of the ancestry of elementary particle physics, there are once again lessons to be learned from it. I shall discuss several of these, including some that have emerged at CERN and Brookhaven.

  3. Physical qubits from charged particles: Infrared divergences in quantum information

    SciTech Connect

    Leon, Juan; Martin-Martinez, Eduardo

    2009-05-15

    We consider soft-photon effects (ir structure of QED) on the construction of physical qubits. Soft photons appear when we build charged qubits from the asymptotic states of QED. This construction is necessary in order to include the effect of soft photons on entanglement measures. The nonexistence of free charged particles (due to the long range of QED interactions) leads us to question the sense of the very concept of free charged qubit. In this work, using the ''dressing'' formalism, we build physical charged qubits from dressed fields which have the correct asymptotic behavior, are gauge invariant, have propagators with a particle pole structure, and are free from infrared divergences. Finally, we discuss the impact of the soft corrections on the entanglement measures.

  4. Quantum Particles From Quantum Information

    NASA Astrophysics Data System (ADS)

    Görnitz, T.; Schomäcker, U.

    2012-08-01

    Many problems in modern physics demonstrate that for a fundamental entity a more general conception than quantum particles or quantum fields are necessary. These concepts cannot explain the phenomena of dark energy or the mind-body-interaction. Instead of any kind of "small elementary building bricks", the Protyposis, an abstract and absolute quantum information, free of special denotation and open for some purport, gives the solution in the search for a fundamental substance. However, as long as at least relativistic particles are not constructed from the Protyposis, such an idea would remain in the range of natural philosophy. Therefore, the construction of relativistic particles without and with rest mass from quantum information is shown.

  5. Quantum Concepts in Physics

    NASA Astrophysics Data System (ADS)

    Longair, Malcolm

    2013-01-01

    Part I. The Discovery of Quanta: 1. Physics and theoretical physics in 1895; 2. Planck and black-body radiation; 3. Einstein and quanta, 1900-1911; Part II. The Old Quantum Theory: 4. The Bohr model of the hydrogen atom; 5. Sommerfield and Ehrenfest - generalising the Bohr model; 6. Einstein coefficients, Bohr's correspondence principle and the first selection rules; 7. Understanding atomic spectra - additional quantum numbers; 8. Bohr's model of the periodic table and the origin of spin; 9. The wave-particle duality; Part III. The Discovery of Quantum Mechanics; 10. The collapse of the old quantum theory and the seeds of its regeneration; 11. The Heisenberg breakthrough; 12. Matrix mechanics; 13. Dirac's quantum mechanics; 14. Schrödinger and wave mechanics; 15. Reconciling matrix and wave mechanics; 16. Spin and quantum statistics; 17. The interpretation of quantum mechanics; 18. The aftermath; 19. Epilogue; Indices.

  6. Quantum Physics for Beginners.

    ERIC Educational Resources Information Center

    Strand, J.

    1981-01-01

    Suggests a new approach for teaching secondary school quantum physics. Reviews traditional approaches and presents some characteristics of the three-part "Quantum Physics for Beginners" project, including: quantum physics, quantum mechanics, and a short historical survey. (SK)

  7. Research in theoretical particle physics

    SciTech Connect

    McKay, D.W.; Munczek, H.; Ralston, J.

    1992-05-01

    This report discusses the following topics in high energy physics: dynamical symmetry breaking and Schwinger-Dyson equation; consistency bound on the minimal model Higgs mass; tests of physics beyond the standard model; particle astrophysics; the interface between perturbative and non-perturbative QCD; cosmology; anisotropy in quantum networks and integer quantum hall behavior; anomalous color transparency; quantum treatment of solitons; color transparency; quantum stabilization of skyrmions; and casimir effect. (LSP)

  8. "Loops and Legs in Quantum Field Theory", 12th DESY Workshop on Elementary Particle Physics

    NASA Astrophysics Data System (ADS)

    The bi-annual international conference "Loops and Legs in Quantum Field Theory" has been held at Weimar, Germany, from April 27 to May 02, 2014. It has been the 12th conference of this series, started in 1992. The main focus of the conference are precision calculations of multi- loop and multi-leg processes in elementary particle physics for processes at present and future high-energy facilities within and beyond the Standard Model. At present many physics questions studied deal with processes at the LHC and future facilities like the ILC. A growing number of contributions deals with important developments in the field of computational technologies and algorithmic methods, including large-scale computer algebra, efficient methods to compute large numbers of Feynman diagrams, analytic summation and integration methods of various kinds, new related function spaces, precise numerical methods and Monte Carlo simulations. The present conference has been attended by more than 110 participants from all over the world, presenting more than 75 contributions, most of which have been written up for these pro- ceedings. The present volume demonstrates in an impressive way the enormous development of the field during the last few years, reaching the level of 5-loop calculations in QCD and a like- wise impressive development in massive next-to-leading order and next-to-next-to-leading order processes. Computer algebraic and numerical calculations require terabyte storage and many CPU years, even after intense parallelization, to obtain state-of-the-art theoretical predictions. The city of Weimar gave a suitable frame to the conference, with its rich history, especially in literature, music, arts, and architecture. Goethe, Schiller, Wieland, Herder, Bach and Liszt lived there and created many of their masterpieces. The many young participants signal that our field is prosperous and faces an exciting future. The conference hotel "Kaiserin Augusta" offered a warm hospitality and

  9. The Birth of Elementary-Particle Physics.

    ERIC Educational Resources Information Center

    Brown, Laurie M.; Hoddeson, Lillian

    1982-01-01

    Traces the origin and development of particle physics, concentrating on the roles of cosmic rays and theory. Includes charts highlighting significant events in the development of cosmic-ray physics and quantum field theory. (SK)

  10. How a single particle simultaneously modifies the physical reality of two distant others: a quantum nonlocality and weak value study

    PubMed Central

    de Lima Bernardo, Bertúlio; Canabarro, Askery; Azevedo, Sérgio

    2017-01-01

    The concept of wave-particle duality, which is a key element of quantum theory, has been remarkably found to manifest itself in several experimental realizations as in the famous double-slit experiment. In this specific case, a single particle seems to travel through two separated slits simultaneously. Nevertheless, it is never possible to measure it in both slits, which naturally appears as a manifestation of the collapse postulate. In this respect, one could as well ask if it is possible to “perceive” the presence of the particle at the two slits simultaneously, once its collapse could be avoided. In this article, we use the recently proposed entanglement mediation protocol to provide a positive answer to this question. It is shown that a photon which behaves like a wave, i.e., which seems to be present in two distant locations at the same time, can modify two existing physical realities in these locations. Calculations of the “weak trace” left by such photon also enforce the validity of the present argumentation. PMID:28045059

  11. How a single particle simultaneously modifies the physical reality of two distant others: a quantum nonlocality and weak value study

    NASA Astrophysics Data System (ADS)

    de Lima Bernardo, Bertúlio; Canabarro, Askery; Azevedo, Sérgio

    2017-01-01

    The concept of wave-particle duality, which is a key element of quantum theory, has been remarkably found to manifest itself in several experimental realizations as in the famous double-slit experiment. In this specific case, a single particle seems to travel through two separated slits simultaneously. Nevertheless, it is never possible to measure it in both slits, which naturally appears as a manifestation of the collapse postulate. In this respect, one could as well ask if it is possible to “perceive” the presence of the particle at the two slits simultaneously, once its collapse could be avoided. In this article, we use the recently proposed entanglement mediation protocol to provide a positive answer to this question. It is shown that a photon which behaves like a wave, i.e., which seems to be present in two distant locations at the same time, can modify two existing physical realities in these locations. Calculations of the “weak trace” left by such photon also enforce the validity of the present argumentation.

  12. Quantum physics meets biology.

    PubMed

    Arndt, Markus; Juffmann, Thomas; Vedral, Vlatko

    2009-12-01

    Quantum physics and biology have long been regarded as unrelated disciplines, describing nature at the inanimate microlevel on the one hand and living species on the other hand. Over the past decades the life sciences have succeeded in providing ever more and refined explanations of macroscopic phenomena that were based on an improved understanding of molecular structures and mechanisms. Simultaneously, quantum physics, originally rooted in a world-view of quantum coherences, entanglement, and other nonclassical effects, has been heading toward systems of increasing complexity. The present perspective article shall serve as a "pedestrian guide" to the growing interconnections between the two fields. We recapitulate the generic and sometimes unintuitive characteristics of quantum physics and point to a number of applications in the life sciences. We discuss our criteria for a future "quantum biology," its current status, recent experimental progress, and also the restrictions that nature imposes on bold extrapolations of quantum theory to macroscopic phenomena.

  13. Experimental Particle Physics

    SciTech Connect

    Rosenfeld, Carl; Mishra, Sanjib R.; Petti, Roberto; Purohit, Milind V.

    2014-08-31

    The high energy physics group at the University of South Carolina, under the leadership of Profs. S.R. Mishra, R. Petti, M.V. Purohit, J.R. Wilson (co-PI's), and C. Rosenfeld (PI), engaged in studies in "Experimental Particle Physics." The group collaborated with similar groups at other universities and at national laboratories to conduct experimental studies of elementary particle properties. We utilized the particle accelerators at the Fermi National Accelerator Laboratory (Fermilab) in Illinois, the Stanford Linear Accelerator Center (SLAC) in California, and the European Center for Nuclear Research (CERN) in Switzerland. Mishra, Rosenfeld, and Petti worked predominantly on neutrino experiments. Experiments conducted in the last fifteen years that used cosmic rays and the core of the sun as a source of neutrinos showed conclusively that, contrary to the former conventional wisdom, the "flavor" of a neutrino is not immutable. A neutrino of flavor "e," "mu," or "tau," as determined from its provenance, may swap its identity with one of the other flavors -- in our jargon, they "oscillate." The oscillation phenomenon is extraordinarily difficult to study because neutrino interactions with our instruments are exceedingly rare -- they travel through the earth mostly unimpeded -- and because they must travel great distances before a substantial proportion have made the identity swap. Three of the experiments that we worked on, MINOS, NOvA, and LBNE utilize a beam of neutrinos from an accelerator at Fermilab to determine the parameters governing the oscillation. Two other experiments that we worked on, NOMAD and MIPP, provide measurements supportive of the oscillation experiments. Good measurements of the neutrino oscillation parameters may constitute a "low energy window" on related phenomena that are otherwise unobservable because they would occur only at energies way above the reach of conceivable accelerators. Purohit and Wilson participated in the BaBar experiment

  14. Particle physics: Axions exposed

    NASA Astrophysics Data System (ADS)

    Lombardo, Maria Paola

    2016-11-01

    Physicists are hunting for a particle called the axion that could solve two major puzzles in fundamental physics. An ambitious study calculates the expected mass of this particle, which might reshape the experimental searches. See Letter p.69

  15. Quantum particle interacting with a metallic particle: Spectra from quantum Langevin theory

    NASA Astrophysics Data System (ADS)

    Loh, W. M. Edmund; Ooi, C. H. Raymond

    2017-01-01

    The effect of a nearby metallic particle on the quantum optical properties of a quantum particle in the four-level double Raman configuration is studied using the quantum Langevin approach. We obtain analytical expressions for the correlated quantum fields of Stokes and anti-Stokes photons emitted from the system and perform analysis on how the interparticle distance, the direction of observation or detection, the strengths of controllable laser fields, the presence of surface plasmon resonance, and the number density of the quantum particle affect the quantum spectra of the Stokes and anti-Stokes fields. We explore the physics behind the quantum-particle-metallic-nanoparticle interaction within the dipole approximation, that is, when the interparticle distance is much larger than the sizes of the particles. Our results show the dependence of the spectra on the interparticle distance in the form of oscillatory behavior with damping as the interparticle distance increases. At weaker laser fields the enhancement of quantum fields which manifests itself in the form of a Fano dip in the central peak of the spectra becomes significant. Also, the quantum-particle-metallic-nanoparticle coupling, which is affected by the size of the metallic nanoparticle and the number density of the quantum particle, changes the angular dependence of the spectra by breaking the angular rotational symmetry. In the presence of surface plasmon resonance the oscillatory dependence of the spectra on the interparticle distance and angles of observation becomes even stronger due to the plasmonic enhancement effect.

  16. Quantum physics meets biology

    PubMed Central

    Arndt, Markus; Juffmann, Thomas; Vedral, Vlatko

    2009-01-01

    Quantum physics and biology have long been regarded as unrelated disciplines, describing nature at the inanimate microlevel on the one hand and living species on the other hand. Over the past decades the life sciences have succeeded in providing ever more and refined explanations of macroscopic phenomena that were based on an improved understanding of molecular structures and mechanisms. Simultaneously, quantum physics, originally rooted in a world-view of quantum coherences, entanglement, and other nonclassical effects, has been heading toward systems of increasing complexity. The present perspective article shall serve as a “pedestrian guide” to the growing interconnections between the two fields. We recapitulate the generic and sometimes unintuitive characteristics of quantum physics and point to a number of applications in the life sciences. We discuss our criteria for a future “quantum biology,” its current status, recent experimental progress, and also the restrictions that nature imposes on bold extrapolations of quantum theory to macroscopic phenomena. PMID:20234806

  17. Elementary particle physics

    NASA Technical Reports Server (NTRS)

    Perkins, D. H.

    1986-01-01

    Elementary particle physics is discussed. Status of the Standard Model of electroweak and strong interactions; phenomena beyond the Standard Model; new accelerator projects; and possible contributions from non-accelerator experiments are examined.

  18. Research program in particle physics

    SciTech Connect

    Sudarshan, E.C.G.; Dicus, D.A.; Ritchie, J.L.; Lang, K.

    1992-07-01

    This report discusses the following topics: Quantum Gravity and Mathematical Physics; Phenomenology; Quantum Mechanics and Quantum Field Theory; Status of BNL Expt. 791; BNL Expt. 791; BNL Expt. 888; and SSC Activities.

  19. RESEARCH IN PARTICLE PHYSICS

    SciTech Connect

    Kearns, Edward

    2013-07-12

    This is the final report for the Department of Energy Grant to Principal Investigators in Experimental and Theoretical Particle Physics at Boston University. The research performed was in the Energy Frontier at the LHC, the Intensity Frontier at Super-Kamiokande and T2K, the Cosmic Frontier and detector R&D in dark matter detector development, and in particle theory.

  20. Review of particle physics

    SciTech Connect

    Olive, K. A.

    2016-10-01

    The Review summarizes much of particle physics and cosmology. Using data from previous editions, plus 3,062 new measurements from 721 papers, we list, evaluate, and average measured properties of gauge bosons and the recently discovered Higgs boson, leptons, quarks, mesons, and baryons. We summarize searches for hypothetical particles such as supersymmetric particles, heavy bosons, axions, dark photons, etc. All the particle properties and search limits are listed in Summary Tables. We also give numerous tables, figures, formulae, and reviews of topics such as Higgs Boson Physics, Supersymmetry, Grand Unified Theories, Neutrino Mixing, Dark Energy, Dark Matter, Cosmology, Particle Detectors, Colliders, Probability and Statistics. As a result, among the 117 reviews are many that are new or heavily revised, including those on Pentaquarks and Inflation.

  1. Review of particle physics

    DOE PAGES

    Olive, K. A.

    2016-10-01

    The Review summarizes much of particle physics and cosmology. Using data from previous editions, plus 3,062 new measurements from 721 papers, we list, evaluate, and average measured properties of gauge bosons and the recently discovered Higgs boson, leptons, quarks, mesons, and baryons. We summarize searches for hypothetical particles such as supersymmetric particles, heavy bosons, axions, dark photons, etc. All the particle properties and search limits are listed in Summary Tables. We also give numerous tables, figures, formulae, and reviews of topics such as Higgs Boson Physics, Supersymmetry, Grand Unified Theories, Neutrino Mixing, Dark Energy, Dark Matter, Cosmology, Particle Detectors, Colliders,more » Probability and Statistics. As a result, among the 117 reviews are many that are new or heavily revised, including those on Pentaquarks and Inflation.« less

  2. Cosmology and Particle Physics

    NASA Astrophysics Data System (ADS)

    Steigman, G.

    1982-01-01

    The cosmic connections between physics on the very largest and very smallest scales are reviewed with an emphasis on the symbiotic relation between elementary particle physics and cosmology. After a review of the early Universe as a cosmic accelerator, various cosmological and astrophysical constraints on models of particle physics are outlined. To illustrate this approach to particle physics via cosmology, reference is made to several areas of current research: baryon non-conservation and baryon asymmetry; free quarks, heavy hadrons and other exotic relics; primordial nucleosynthesis and neutrino masses. In the last few years we have witnessed the birth and growth to healthy adolescence of a new collaboration between astrophysicists and particle physicists. The most notable success of this cooperative effort has been to provide the framework for understanding, within the context of GUTs and the hot big-bang cosmology, the universal baryon asymmetry. The most exciting new predictions this effort has spawned are that exotic relics may exist in detectable abundances. In particular, we may live in a neutrino-dominated Universe. In the next few years, accummulating laboratory data (for example proton decay, neutrino masses and oscillations) coupled with theoritical work in particle physics and cosmology will ensure the growth to maturity of this joint effort.

  3. Particle physics and cosmology

    SciTech Connect

    Kolb, E.W.

    1986-10-01

    This series of lectures is about the role of particle physics in physical processes that occurred in the very early stages of the bug gang. Of particular interest is the role of particle physics in determining the evolution of the early Universe, and the effect of particle physics on the present structure of the Universe. The use of the big bang as a laboratory for placing limits on new particle physics theories will also be discussed. Section 1 reviews the standard cosmology, including primordial nucleosynthesis. Section 2 reviews the decoupling of weakly interacting particles in the early Universe, and discusses neutrino cosmology and the resulting limits that may be placed on the mass and lifetime of massive neutrinos. Section 3 discusses the evolution of the vacuum through phase transitions in the early Universe and the formation of topological defects in the transitions. Section 4 covers recent work on the generation of the baryon asymmetry by baryon-number violating reactions in Grand Unified Theories, and mentions some recent work on baryon number violation effects at the electroweak transition. Section 5 is devoted to theories of cosmic inflation. Finally, Section 6 is a discussion of the role of extra spatial dimensions in the evolution of the early Universe. 78 refs., 32 figs., 6 tabs.

  4. Operation Quantum Physics

    NASA Astrophysics Data System (ADS)

    Fleming, Gordon N.

    For those at least, like our authors, who embrace an interpretation of quantum theory as realistic, objective and applicable to individual systems, the quantum measurement problem has not been solved and remains a thorn in the side. But quantum measurement theory, i.e. the theory of measurements performable on quantum systems, has evolved considerably from the classic version formulated long ago by Von Neumann (1955), and this book presents a version of the generalised theory and a variety of examples of its application. It can be regarded as a sequel to an earlier book, The Quantum Theory of Measurement by the first and last of the present authors, along with Peter Mittelstaedt (Busch et al., 1991 ). But while the earlier book focused on the authors' philosophical interpretation and the basic physics underlying quantum measurement theory, the present book is more concerned with the resulting mathematical and structural features and with applications. Still, ideology is very present here and the reader should be aware that the book is part of the tradition growing out of the earlier work of Ludwig (1983) and Krause (1983), Ali (1985) and Prugovecki (1986), and Davies (1976) and Holevo (1982). Ludwig and Krause, and the Marburg school generally, sought to understand and interpret quantum theory ultimately in terms of the manipulation of macroscopic systems alone. Ali, Prugovecki and others (Schroeck, 1996) have sought to construct, in quantum theory, the concept of joint probability distributions for sets of non-commuting observables (and thereby, phase space) by generalising the traditional concept of (sharp) observable to include one of unsharp, or fuzzy observable. The classic open system study of Davies and the probability study of Holevo were less driven by ideological concerns.

  5. Quantum Mechanics and physical calculations

    NASA Astrophysics Data System (ADS)

    Karayan, H. S.

    2014-03-01

    We suggest to realize the computer simulation and calculation by the algebraic structure built on the basis of the logic inherent to processes in physical systems (called physical computing). We suggest a principle for the construction of quantum algorithms of neuroinformatics of quantum neural networks. The role of academician Sahakyan is emphasized in the development of quantum physics in Armenia.

  6. Detecting the relative localisation of quantum particles

    NASA Astrophysics Data System (ADS)

    Knott, P. A.; Sindt, J.; Dunningham, J. A.

    2013-06-01

    One interpretation of how the classical world emerges from quantum physics involves the build-up of certain robust entangled states between particles due to scattering events [1]. This is intriguing because it links classical behaviour with the uniquely quantum effect of entanglement and differs from other interpretations that say classicality arises when quantum correlations are lost or neglected in measurements. However, the problem with this new interpretation has been finding an experimental way of verifying it. Here we outline a straightforward scheme that enables just that and should, in principle, allow experiments to confirm the theory to any desired degree of accuracy.

  7. Research in particle physics

    SciTech Connect

    Not Available

    1993-08-01

    This proposal presents the research accomplishments and ongoing activities of Boston University researchers in high energy physics. Some changes have been made in the structure of the program from the previous arrangement of tasks. Task B, Accelerator Design Physics, is being submitted as a separate proposal for an independent grant; this will be consistent with the nature of the research and the source of funding. We are active in seven principal areas which will be discussed in this report: Colliding Beams - physics of e{sup +}e{sup {minus}} and {bar p}p collisions; MACRO Experiment - search for magnetic monopoles and study of cosmic rays; Proton Decay - search for nucleon instability and study of neutrino interactions; Particle Theory - theoretical high energy particle physics, including two Outstanding Junior Investigator awards; Muon G-2 - measurement of the anomalous magnetic moment of the muon; SSCintcal - calorimetry for the GEM Experiment; and Muon detectors for the GEM Experiment.

  8. Quantum optics. Gravity meets quantum physics

    SciTech Connect

    Adams, Bernhard W.

    2015-02-27

    Albert Einstein’s general theory of relativity is a classical formulation but a quantum mechanical description of gravitational forces is needed, not only to investigate the coupling of classical and quantum systems but simply to give a more complete description of our physical surroundings. In this issue of Nature Photonics, Wen-Te Liao and Sven Ahrens reveal a link between quantum and gravitational physics. They propose that in the quantum-optical effect of superradiance, the world line of electromagnetic radiation is changed by the presence of a gravitational field.

  9. Review of Particle Physics

    NASA Astrophysics Data System (ADS)

    Olive, K. A.; Particle Data Group; et al.

    2016-10-01

    The Review summarizes much of particle physics and cosmology. Using data from previous editions, plus 3,062 new measurements from 721 papers, we list, evaluate, and average measured properties of gauge bosons and the recently discovered Higgs boson, leptons, quarks, mesons, and baryons. We summarize searches for hypothetical particles such as supersymmetric particles, heavy bosons, axions, dark photons, etc. All the particle properties and search limits are listed in Summary Tables. We also give numerous tables, figures, formulae, and reviews of topics such as Higgs Boson Physics, Supersymmetry, Grand Unified Theories, Neutrino Mixing, Dark Energy, Dark Matter, Cosmology, Particle Detectors, Colliders, Probability and Statistics. Among the 117 reviews are many that are new or heavily revised, including those on Pentaquarks and Inflation. The complete Review is published online in a journal and on the website of the Particle Data Group (http://pdg.lbl.gov). The printed PDG Book contains the Summary Tables and all review articles but no longer includes the detailed tables from the Particle Listings. A Booklet with the Summary Tables and abbreviated versions of some of the review articles is also available. Contents Abstract, Contributors, Highlights and Table of ContentsAcrobat PDF (150 KB) IntroductionAcrobat PDF (456 KB) Particle Physics Summary Tables Gauge and Higgs bosonsAcrobat PDF (155 KB) LeptonsAcrobat PDF (134 KB) QuarksAcrobat PDF (84 KB) MesonsAcrobat PDF (871 KB) BaryonsAcrobat PDF (300 KB) Searches (Supersymmetry, Compositeness, etc.)Acrobat PDF (91 KB) Tests of conservation lawsAcrobat PDF (330 KB) Reviews, Tables, and Plots Detailed contents for this sectionAcrobat PDF (37 KB) Constants, Units, Atomic and Nuclear PropertiesAcrobat PDF (278 KB) Standard Model and Related TopicsAcrobat PDF (7.3 MB) Astrophysics and CosmologyAcrobat PDF (2.7 MB) Experimental Methods and CollidersAcrobat PDF (3.8 MB) Mathematical Tools or Statistics, Monte Carlo, Group

  10. Field theory and particle physics

    SciTech Connect

    Eboli, O.J.P.; Gomes, M.; Santoro, A.

    1990-01-01

    This book contains the proceedings of the topics covered during the fifth Jorge Andre Swieca Summer School. The first part of the book collects the material devoted to quantum field theory. There were four courses on methods in Field Theory; H. O. Girotti lectured on constrained dynamics, R. Jackiw on the Schrodinger representation in Field Theory, S.-Y. Pi on the application of this representation to quantum fields in a Robertson-Walker spacetime, and L. Vinet on Berry Connections. There were three courses on Conformal Field Theory: I. Todorov focused on the problem of construction and classification of conformal field theories. Lattice models, two-dimensional S matrices and conformal field theory were looked from the unifying perspective of the Yang-Baxter algebras in the lectures given by M. Karowski. Parasupersymmetric quantum mechanics was discussed in the lectures by L. Vinet. Besides those courses, there was an introduction to string field theory given by G. Horowitz. There were also three seminars: F. Schaposnik reported on recent applications of topological methods in field theory, P. Gerbert gave a seminar on three dimensional gravity and V. Kurak talked on two dimensional parafermionic models. The second part of this proceedings is devoted to phenomenology. There were three courses on Particle Physics: Dan Green lectured on collider physics, E. Predrazzi on strong interactions and G. Cohen-Tanoudji on the use of strings in strong interactions.

  11. Algebraic formulation of quantum theory, particle identity and entanglement

    NASA Astrophysics Data System (ADS)

    Govindarajan, T. R.

    2016-08-01

    Quantum theory as formulated in conventional framework using statevectors in Hilbert spaces misses the statistical nature of the underlying quantum physics. Formulation using operators 𝒞∗ algebra and density matrices appropriately captures this feature in addition leading to the correct formulation of particle identity. In this framework, Hilbert space is an emergent concept. Problems related to anomalies and quantum epistemology are discussed.

  12. Increasing complexity with quantum physics.

    PubMed

    Anders, Janet; Wiesner, Karoline

    2011-09-01

    We argue that complex systems science and the rules of quantum physics are intricately related. We discuss a range of quantum phenomena, such as cryptography, computation and quantum phases, and the rules responsible for their complexity. We identify correlations as a central concept connecting quantum information and complex systems science. We present two examples for the power of correlations: using quantum resources to simulate the correlations of a stochastic process and to implement a classically impossible computational task.

  13. Particle physics -- Future directions

    SciTech Connect

    Chris Quigg

    2001-11-29

    Wonderful opportunities await particle physics over the next decade, with the coming of the Large Hadron Collider at CERN to explore the 1-TeV scale (extending efforts at LEP and the Tevatron to unravel the nature of electroweak symmetry breaking) and many initiatives to develop our understanding of the problem of identity: what makes a neutrino a neutrino and a top quark a top quark. Here I have in mind the work of the B factories and the Tevatron collider on CP violation and the weak interactions of the b quark; the wonderfully sensitive experiments at Brookhaven, CERN, Fermilab, and Frascati on CP violation and rare decays of kaons; the prospect of definitive accelerator experiments on neutrino oscillations and the nature of the neutrinos; and a host of new experiments on the sensitivity frontier. We might even learn to read experiment for clues about the dimensionality of spacetime. If we are inventive enough, we may be able to follow this rich menu with the physics opportunities offered by a linear collider and a (muon storage ring) neutrino factory. I expect a remarkable flowering of experimental particle physics, and of theoretical physics that engages with experiment. I describe some of the great questions before us and the challenges of providing the instruments that will be needed to define them more fully and eventually to answer them.

  14. Quantum vacuum noise in physics and cosmology.

    PubMed

    Davies, P. C. W.

    2001-09-01

    The concept of the vacuum in quantum field theory is a subtle one. Vacuum states have a rich and complex set of properties that produce distinctive, though usually exceedingly small, physical effects. Quantum vacuum noise is familiar in optical and electronic devices, but in this paper I wish to consider extending the discussion to systems in which gravitation, or large accelerations, are important. This leads to the prediction of vacuum friction: The quantum vacuum can act in a manner reminiscent of a viscous fluid. One result is that rapidly changing gravitational fields can create particles from the vacuum, and in turn the backreaction on the gravitational dynamics operates like a damping force. I consider such effects in early universe cosmology and the theory of quantum black holes, including the possibility that the large-scale structure of the universe might be produced by quantum vacuum noise in an early inflationary phase. I also discuss the curious phenomenon that an observer who accelerates through a quantum vacuum perceives a bath of thermal radiation closely analogous to Hawking radiation from black holes, even though an inertial observer registers no particles. The effects predicted raise very deep and unresolved issues about the nature of quantum particles, the role of the observer, and the relationship between the quantum vacuum and the concepts of information and entropy. (c) 2001 American Institute of Physics.

  15. Lithography using quantum entangled particles

    NASA Technical Reports Server (NTRS)

    Williams, Colin (Inventor); Dowling, Jonathan (Inventor); della Rossa, Giovanni (Inventor)

    2003-01-01

    A system of etching using quantum entangled particles to get shorter interference fringes. An interferometer is used to obtain an interference fringe. N entangled photons are input to the interferometer. This reduces the distance between interference fringes by n, where again n is the number of entangled photons.

  16. Lithography using quantum entangled particles

    NASA Technical Reports Server (NTRS)

    Williams, Colin (Inventor); Dowling, Jonathan (Inventor)

    2001-01-01

    A system of etching using quantum entangled particles to get shorter interference fringes. An interferometer is used to obtain an interference fringe. N entangled photons are input to the interferometer. This reduces the distance between interference fringes by n, where again n is the number of entangled photons.

  17. Cosmology and particle physics

    NASA Technical Reports Server (NTRS)

    Turner, Michael S.

    1988-01-01

    The interplay between cosmology and elementary particle physics is discussed. The standard cosmology is reviewed, concentrating on primordial nucleosynthesis and discussing how the standard cosmology has been used to place constraints on the properties of various particles. Baryogenesis is discussed, showing how a scenario in which the B-, C-, and CP-violating interactions in GUTs provide a dynamical explanation for the predominance of matter over antimatter and for the present baryon-to-photon ratio. It is shown how the very early dynamical evolution of a very weakly coupled scalar field which is initially displaced from the minimum of its potential may explain a handful of very fundamental cosmological facts which are not explained by the standard cosmology.

  18. Physics of windblown particles

    NASA Technical Reports Server (NTRS)

    Greeley, Ronald; Leach, Rodman; Marshall, John R.; White, Bruce; Iversen, James D.; Nickling, William G.; Gillette, Dale; Sorensen, Michael

    1987-01-01

    A laboratory facility proposed for the Space Station to investigate fundamental aspects of windblown particles is described. The experiments would take advantage of the environment afforded in earth orbit and would be an extension of research currently being conducted on the geology and physics of windblown sediments on earth, Mars, and Venus. Aeolian (wind) processes are reviewed in the planetary context, the scientific rational is given for specific experiments to be conducted, the experiment apparatus (the Carousel Wind Tunnel, or CWT) is described, and a plan presented for implementing the proposed research program.

  19. Elementary Particles and the Laws of Physics

    NASA Astrophysics Data System (ADS)

    Feynman, Richard P.; Weinberg, Steven

    1987-11-01

    Developing a theory that seamlessly combines relativity and quantum mechanics, the most important conceptual breakthroughs in twentieth century physics, has proved to be a difficult and ongoing challenge. This book details how two distinguished physicists and Nobel laureates have explored this theme in two lectures given in Cambridge, England, in 1986 to commemorate the famous British physicist Paul Dirac. Given for nonspecialists and undergraduates, the talks transcribed in Elementary Particles and the Laws of Physics focus on the fundamental problems of physics and the present state of our knowledge. Professor Feynman examines the nature of antiparticles, and in particular the relationship between quantum spin and statistics. Professor Weinberg speculates on how Einstein's theory of gravitation might be reconciled with quantum theory in the final law of physics. Highly accessible, deeply thought provoking, this book will appeal to all those interested in the development of modern physics.

  20. The quantum physics of observers

    NASA Astrophysics Data System (ADS)

    Mills, B. I.

    2002-08-01

    The observer is herein studied as an aspect of laboratory physics. It is generally accepted that our status as observers is mediated by our material aspects: our body and brain. But, observers are typically equated with classical coordinate systems. An alternative, modelling the observer as a quantum entity, is considered. The corresponding transformations between two quantum observers affect the computed wavefunctions of other quantum entities in a physically meaningful manner.

  1. Parables of Physics and a Quantum Romance

    ERIC Educational Resources Information Center

    Machacek, A. C.

    2014-01-01

    Teachers regularly use stories to amplify the concepts taught and to encourage student engagement. The literary form of a parable is particularly suitable for classroom use, and examples are given, including a longer one intended to stimulate discussion on the nature of quantum physics (and the wave-particle duality in particular).

  2. Parables of physics and a quantum romance

    NASA Astrophysics Data System (ADS)

    Machacek, A. C.

    2014-01-01

    Teachers regularly use stories to amplify the concepts taught and to encourage student engagement. The literary form of a parable is particularly suitable for classroom use, and examples are given, including a longer one intended to stimulate discussion on the nature of quantum physics (and the wave-particle duality in particular).

  3. Particle physics---Experimental

    SciTech Connect

    Lord, J.J.; Boynton, P.E.; Burnett, T.H.; Wilkes, R.J.

    1991-08-21

    We are continuing a research program in particle astrophysics and high energy experimental particle physics. We have joined the DUMAND Collaboration, which is constructing a deep undersea astrophysical neutrino detector near Hawaii. Studies of high energy hadronic interactions using emulsion chamber techniques were also continued, using balloon flight exposures to ultra-high cosmic ray nuclei (JACEE) and accelerator beams. As members of the DUMAND Collaboration, we have responsibility for development a construction of critical components for the deep undersea neutrino detector facility. We have designed and developed the acoustical positioning system required to permit reconstruction of muon tracks with sufficient precision to meet the astrophysical goals of the experiment. In addition, we are making significant contributions to the design of the database and triggering system to be used. Work has been continuing in other aspects of the study of multiparticle production processes in nuclei. We are participants in a joint US/Japan program to study nuclear interactions at energies two orders of magnitude greater than those of existing accelerators, using balloon-borne emulsion chambers. On one of the flights we found two nuclear interactions of multiplicity over 1000 -- one with a multiplicity of over 2000 and pseudorapidity density {approximately} 800 in the central region. At the statistical level of the JACEE experiment, the frequency of occurrence of such events is orders of magnitude too large. We have continued our ongoing program to study hadronic interactions in emulsions exposed to high energy accelerator beams.

  4. Dirac particle in gravitational quantum mechanics

    NASA Astrophysics Data System (ADS)

    Pedram, Pouria

    2011-08-01

    In this Letter, we consider the effects of the Generalized (Gravitational) Uncertainty Principle (GUP) on the eigenvalues and the eigenfunctions of the Dirac equation. This form of GUP is consistent with various candidates of quantum gravity such as string theory, loop quantum gravity, doubly special relativity and black hole physics and predicts both a minimum measurable length and a maximum measurable momentum. The modified Hamiltonian contains two additional terms proportional to a( and a( where αi are Dirac matrices and a∼1/MPlc is the GUP parameter. For the case of the Dirac free particle and the Dirac particle in a box, we solve the generalized Dirac equation and find the modified energy eigenvalues and eigenfunctions.

  5. Quantum evaporation of flavor-mixed particles

    NASA Astrophysics Data System (ADS)

    Medvedev, Mikhail V.

    2014-03-01

    Particles whose propagation (mass) and interaction (flavor) bases are misaligned are mixed, e.g., neutrinos, quarks, Kaons, etc. We show that interactions (elastic scattering) of individual mass-eigenstates can result in their inter-conversions. Most intriguing and counter-intuitive implication of this process is a new process, which we refer to as the ``quantum evaporation.'' Consider a mixed particle trapped in a gravitational potential. If such a particle scatters off something (e.g., from another mixed particle) elastically from time to time, this particle (or both particles, respectively) can eventually escape to infinity with no extra energy supplied. That is as if a ``flavor-mixed satellite'' hauled along a bumpy road puts itself in space without a rocket, fuel, etc. Of course, the process at hand is entirely quantum and has no counterpart in classical mechanics. It also has nothing to do with tunneling or other known processes. We discuss some implications to the dark matter physics, cosmology and cosmic neutrino background. Supported by grant DOE grant DE-FG02-07ER54940 and NSF grant AST-1209665.

  6. Teaching Quantum Physics without Paradoxes

    ERIC Educational Resources Information Center

    Hobson, Art

    2007-01-01

    Although the resolution to the wave-particle paradox has been known for 80 years, it is seldom presented. Briefly, the resolution is that material particles and photons are the quanta of extended spatially continuous but energetically quantized fields. But because the resolution resides in quantum field theory and is not usually spelled out in…

  7. Multiple-Particle Interference and Quantum Error Correction

    NASA Astrophysics Data System (ADS)

    Steane, Andrew

    1996-11-01

    The concept of multiple-particle interference is discussed, using insights provided by the classical theory of error correcting codes. This leads to a discussion of error correction in a quantum communication channel or a quantum computer. Methods of error correction in the quantum regime are presented, and their limitations assessed. A quantum channel can recover from arbitrary decoherence of x qubits if K bits of quantum information are encoded using n quantum bits, where K/n can be greater than 1 - 2H (2x/n), but must be less than 1 - 2H (x/n). This implies exponential reduction of decoherence with only a polynomial increase in the computing resources required. Therefore quantum computation can be made free of errors in the presence of physically realistic levels of decoherence. The methods also allow isolation of quantum communication from noise and evesdropping (quantum privacy amplification).

  8. Particle Physics Masterclass

    ScienceCinema

    Helio Takai

    2016-07-12

    Students from six local high schools -- Farmingdale, Sachem East, Shoreham, Smithtown East, Ward Melville, and William Floyd -- came to Brookhaven National Laboratory to experience research with particle physicist Helio Takai. They were among more than 6,

  9. Particle Physics Masterclass

    SciTech Connect

    Helio Takai

    2009-04-10

    Students from six local high schools -- Farmingdale, Sachem East, Shoreham, Smithtown East, Ward Melville, and William Floyd -- came to Brookhaven National Laboratory to experience research with particle physicist Helio Takai. They were among more than 6,

  10. Quantum physics and complex networks

    NASA Astrophysics Data System (ADS)

    Biamonte, Jacob

    2014-03-01

    There is a widely used and successful theory of ``chemical reaction networks,'' which provides a framework describing systems governed by mass action kinetics. Computer science and population biology use the same ideas under a different name: ``stochastic Petri nets.'' But if we look at these theories from the perspective of quantum theory, they turn out to involve creation and annihilation operators, coherent states and other well-known ideas--yet in a context where probabilities replace amplitudes. I will explain this connection as part of a detailed analogy between quantum mechanics and stochastic mechanics which we've produced several results on recently, including the recent analytical results uniting quantum physics and complex networks. Our general idea is about merging concepts from quantum physics and complex network theory to provide a bidirectional bridge between both disciplines. Support is acknowledged from the Foundational Questions Institute (FQXi) and the Compagnia di San Paolo Foundation.

  11. Towards testing quantum physics in deep space

    NASA Astrophysics Data System (ADS)

    Kaltenbaek, Rainer

    2016-07-01

    MAQRO is a proposal for a medium-sized space mission to use the unique environment of deep space in combination with novel developments in space technology and quantum technology to test the foundations of physics. The goal is to perform matter-wave interferometry with dielectric particles of up to 10^{11} atomic mass units and testing for deviations from the predictions of quantum theory. Novel techniques from quantum optomechanics with optically trapped particles are to be used for preparing the test particles for these experiments. The core elements of the instrument are placed outside the spacecraft and insulated from the hot spacecraft via multiple thermal shields allowing to achieve cryogenic temperatures via passive cooling and ultra-high vacuum levels by venting to deep space. In combination with low force-noise microthrusters and inertial sensors, this allows realizing an environment well suited for long coherence times of macroscopic quantum superpositions and long integration times. Since the original proposal in 2010, significant progress has been made in terms of technology development and in refining the instrument design. Based on these new developments, we submitted/will submit updated versions of the MAQRO proposal in 2015 and 2016 in response to Cosmic-Vision calls of ESA for a medium-sized mission. A central goal has been to address and overcome potentially critical issues regarding the readiness of core technologies and to provide realistic concepts for further technology development. We present the progress on the road towards realizing this ground-breaking mission harnessing deep space in novel ways for testing the foundations of physics, a technology pathfinder for macroscopic quantum technology and quantum optomechanics in space.

  12. Physics as quantum information processing

    NASA Astrophysics Data System (ADS)

    Mauro D'Ariano, Giacomo

    2011-10-01

    The experience from Quantum Information has lead us to look at Quantum Theory (QT) and the whole Physics from a different angle. The information-theoretical paradigm—It from Bit— prophesied by John Archibald Wheeler is relentlessly advancing. Recently it has been shown that QT is derivable from pure informational principles. The possibility that there is only QT at the foundations of Physics has been then considered, with space-time, Relativity, quantization rules and Quantum Field Theory (QFT) emerging from a quantum-information processing. The resulting theory is a discrete version of QFT with automatic relativistic invariance, and without fields, Hamiltonian, and quantization rules. In this paper I review some recent advances on these lines. In particular: i) How space-time and relativistic covariance emerge from the quantum computation; ii) The derivation of the Dirac equation as free information flow, without imposing Lorentz covariance; iii) the information-theoretical meaning of inertial mass and Planck constant; iv) An observable consequence of the theory: a mass-dependent refraction index of vacuum. I will then conclude with two possible routes to Quantum Gravity.

  13. Theoretical particle physics

    SciTech Connect

    Not Available

    1992-09-30

    This report discusses the following topics: heavy quark physics; Chiral Perturbation theory; Skyrmions; quarkonia and nuclear matter; parity violating nuclear matrix elements; how precisely can one determine M{sub U}/M{sub D}; weak scale baryogenesis; constraints of baryogenesis form neutrino masses; majorons, double beta decay, supernova 1987A; rare decays; chiral lattice fermions; Pauli-Villars regulator and the Higgs mass bound; and Higgs and Yukawa interactions.

  14. Nuclear physics and particle therapy

    NASA Astrophysics Data System (ADS)

    Battistoni, G.

    2016-05-01

    The use of charged particles and nuclei in cancer therapy is one of the most successful cases of application of nuclear physics to medicine. The physical advantages in terms of precision and selectivity, combined with the biological properties of densely ionizing radiation, make charged particle approach an elective choice in a number of cases. Hadron therapy is in continuous development and nuclear physicists can give important contributions to this discipline. In this work some of the relevant aspects in nuclear physics will be reviewed, summarizing the most important directions of research and development.

  15. The Multiverse and Particle Physics

    NASA Astrophysics Data System (ADS)

    Donoghue, John F.

    2016-10-01

    The possibility of fundamental theories with very many ground states, each with different physical parameters, changes the way that we approach the major questions of particle physics. Most importantly, it raises the possibility that these different parameters could be realized in different domains in the larger universe. In this review, I survey the motivations for the multiverse and the impact of the idea of the multiverse on the search for new physics beyond the Standard Model.

  16. Quantum fingerprinting with a single particle

    SciTech Connect

    Massar, S.

    2005-01-01

    We show that the two-slit experiment in which a single quantum particle interferes with itself can be interpreted as a quantum fingerprinting protocol: the interference pattern exhibited by the particle contains information about the environment it encountered in the slits which would require much more communication to learn classically than is required quantum mechanically. An extension to the case where the particle has many internal degrees of freedom is suggested, and its interpretation is discussed. The interpretation of these results is discussed in detail, and a possible experimental realization is proposed.

  17. Classical and Quantum Thermal Physics

    NASA Astrophysics Data System (ADS)

    Prasad, R.

    2016-11-01

    List of figures; List of tables; Preface; Acknowledgement; Dedication; 1. The kinetic theory of gases; 2. Ideal to real gas, viscosity, conductivity and diffusion; 3. Thermodynamics: definitions and Zeroth law; 4. First Law of Thermodynamics and some of its applications; 5. Second Law of Thermodynamics and some of its applications; 6. TdS equations and their applications; 7. Thermodynamic functions, potentials, Maxwell equations, the Third Law and equilibrium; 8. Some applications of thermodynamics to problems of physics and engineering; 9. Application of thermodynamics to chemical reactions; 10. Quantum thermodynamics; 11. Some applications of quantum thermodynamics; 12. Introduction to the thermodynamics of irreversible processes; Index.

  18. Clothed Particles in Quantum Electrodynamics and Quantum Chromodynamics

    NASA Astrophysics Data System (ADS)

    Shebeko, Alexander

    2016-03-01

    The notion of clothing in quantum field theory (QFT), put forward by Greenberg and Schweber and developed by M. Shirokov, is applied in quantum electrodynamics (QED) and quantum chromodynamics (QCD). Along the guideline we have derived a novel analytic expression for the QED Hamiltonian in the clothed particle representation (CPR). In addition, we are trying to realize this notion in QCD (to be definite for the gauge group SU(3)) when drawing parallels between QCD and QED.

  19. Unifying Quantum Physics with Biology

    NASA Astrophysics Data System (ADS)

    Goradia, Shantilal

    2014-09-01

    We find that the natural logarithm of the age of the universe in quantum mechanical units is close to 137. Since science is not religion, it is our moral duty to recognize the importance of this finding on the following ground. The experimentally obtained number 137 is a mystical number in science, as if written by the hand of God. It is found in cosmology; unlike other theories, it works in biology too. A formula by Boltzmann also works in both: biology and physics, as if it is in the heart of God. His formula simply leads to finding the logarithm of microstates. One of the two conflicting theories of physics (1) Einstein's theory of General Relativity and (2) Quantum Physics, the first applies only in cosmology, but the second applies in biology too. Since we have to convert the age of the universe, 13 billion years, into 1,300,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000 Planck times to get close to 137, quantum physics clearly shows the characteristics of unifying with biology. The proof of its validity also lies in its ability to extend information system observed in biology.

  20. Quantum dynamics in ultracold atomic physics

    NASA Astrophysics Data System (ADS)

    He, Qiong-Yi; Reid, Margaret D.; Opanchuk, Bogdan; Polkinghorne, Rodney; Rosales-Zárate, Laura E. C.; Drummond, Peter D.

    2012-02-01

    We review recent developments in the theory of quantum dynamics in ultracold atomic physics, including exact techniques and methods based on phase-space mappings that are applicable when the complexity becomes exponentially large. Phase-space representations include the truncated Wigner, positive- P and general Gaussian operator representations which can treat both bosons and fermions. These phase-space methods include both traditional approaches using a phase-space of classical dimension, and more recent methods that use a non-classical phase-space of increased dimensionality. Examples used include quantum Einstein-Podolsky-Rosen (EPR) entanglement of a four-mode BEC, time-reversal tests of dephasing in single-mode traps, BEC quantum collisions with up to 106 modes and 105 interacting particles, quantum interferometry in a multi-mode trap with nonlinear absorption, and the theory of quantum entropy in phase-space. We also treat the approach of variational optimization of the sampling error, giving an elementary example of a nonlinear oscillator.

  1. Introduction to Elementary Particle Physics

    NASA Astrophysics Data System (ADS)

    Salinas, C. J. Solano; Hurtado, K.; Romero, C.

    2009-04-01

    This is a short review of Particle Physics and the most widely accepted theory, the Standard Model, with its questions and limitations. We also show a quick review of some of te theories beyonf the Standard Model. It is based in the introductory talk given the Third School on Cosmic Rays and Astrophysics held in Arequipa, Peru.

  2. A research Program in Elementary Particle Physics

    SciTech Connect

    Sobel, Henry; Molzon, William; Lankford, Andrew; Taffard, Anyes; Whiteson, Daniel; Kirkby, David

    2013-07-25

    Work is reported in: Neutrino Physics, Cosmic Rays and Elementary Particles; Particle Physics and Charged Lepton Flavor Violation; Research in Collider Physics; Dark Energy Studies with BOSS and LSST.

  3. EPR paradox, quantum nonlocality and physical reality

    NASA Astrophysics Data System (ADS)

    Kupczynski, M.

    2016-03-01

    Eighty years ago Einstein, Podolsky and Rosen demonstrated that instantaneous reduction of wave function, believed to describe completely a pair of entangled physical systems, led to EPR paradox. The paradox disappears in statistical interpretation of quantum mechanics (QM) according to which a wave function describes only an ensemble of identically prepared physical systems. QM predicts strong correlations between outcomes of measurements performed on different members of EPR pairs in far-away locations. Searching for an intuitive explanation of these correlations John Bell analysed so called local realistic hidden variable models and proved that correlations consistent with these models satisfy Bell inequalities which are violated by some predictions of QM and by experimental data. Several different local models were constructed and inequalities proven. Some eminent physicists concluded that Nature is definitely nonlocal and that it is acting according to a law of nonlocal randomness. According to these law perfectly random, but strongly correlated events, can be produced at the same time in far away locations and a local and causal explanation of their occurrence cannot be given. We strongly disagree with this conclusion and we prove the contrary by analysing in detail some influential finite sample proofs of Bell and CHSH inequalities and so called Quantum Randi Challenges. We also show how one can win so called Bell's game without violating locality of Nature. Nonlocal randomness is inconsistent with local quantum field theory, with standard model in elementary particle physics and with causal laws and adaptive dynamics prevailing in the surrounding us world. The experimental violation of Bell-type inequalities does not prove the nonlocality of Nature but it only confirms a contextual character of quantum observables and gives a strong argument against counterfactual definiteness and against a point of view according to which experimental outcomes are produced

  4. Repelling, binding, and oscillating of two-particle discrete-time quantum walks

    NASA Astrophysics Data System (ADS)

    Wang, Qinghao; Li, Zhi-Jian

    2016-10-01

    In this paper, we investigate the effects of particle-particle interaction and static force on the propagation of probability distribution in two-particle discrete-time quantum walk, where the interaction and static force are expressed as a collision phase and a linear position-dependent phase, respectively. It is found that the interaction can lead to boson repelling and fermion binding. The static force also induces Bloch oscillation and results in a continuous transition from boson bunching to fermion anti-bunching. The interplays of particle-particle interaction, quantum interference, and Bloch oscillation provide a versatile framework to study and simulate many-particle physics via quantum walks.

  5. Introduction to Quantum Sensors in Cryogenic Particle Detection

    NASA Astrophysics Data System (ADS)

    Kim, Yong-Hamb; Kim, Sun Kee

    Cryogenic detectors have been important tools in many aspects of science because their sensitivities can provide more than extreme limits of conventional semiconductor based detectors. The sensor developments in cryogenic particle detection are based on the precise measurement of noble properties of condensed matter in low temperatures. The major measurement technologies originate from quantum measurements, phase transitions and superconducting electronics. Although the early developments of cryogenic detectors were initiated by applications to elementary particle physics, they have been adopted in biology, forensics, and security as well as astronomy and nuclear science. Various types of cryogenic detectors cover a wide energy range from THz radiations to hundreds MeV particles. We review the recent development of sensor technologies in cryogenic particle detection. The measurement principles are covered together with applications to elementary particle physics and THz measurement.

  6. Research in particle physics. [Dept. of Physics, Boston Univ

    SciTech Connect

    Whitaker, Scott J.

    1992-09-01

    Research accomplishments and current activities of Boston University researchers in high energy physics are presented. Principal areas of activity include the following: detectors for studies of electron[endash]positron annihilation in colliding beams; advanced accelerator component design, including the superconducting beam inflector, electrostatic quadrupoles, and the electrostatic muon kicker''; the detector for the MACRO (Monopole, Astrophysics, and Cosmic Ray Observatory) experiment; neutrino astrophysics and the search for proton decay; theoretical particle physics (electroweak and flavor symmetry breaking, hadron collider phenomenology, cosmology and astrophysics, new field-theoretic models, nonperturbative investigations of quantum field theories, electroweak interactions); measurement of the anomalous magnetic moment of the muon; calorimetry for the GEM experiment; and muon detectors for the GEM experiment at the Superconducting Super Collider.

  7. GPUs in experimental particle physics

    NASA Astrophysics Data System (ADS)

    Berger, Niklaus

    2012-03-01

    Many applications in particle and nuclear physics demand vast computational power with high throughput and low latency. Graphics Processing Units (GPUs) provide such massively parallel floating point computing power at low cost. Indeed many problems are easily parallelized and can be sped up by orders of magnitude by the use of GPUs. The talk will discuss two very different examples, namely the use of GPUs for partial wave analysis and on-line track reconstruction. Partial wave analysis is a key tool in hadron spectroscopy. The unbinned likelihood fits employed are an almost perfect match for the architecture of GPUs. GPU based partial wave analysis was pioneered at the Beijing Spectrometer III experiment in order to deal with world's largest datasets from electron-positron collisions in the charm threshold energy region and is now employed by many groups in the field. The presentation will describe the challenges for implementing a GPU based partial wave analysis and how they were overcome. Usually the most time consuming part of analysing particle physics events is the reconstruction of tracks of charged particles. A new generation of high rate experiments running without a hardware trigger (e.g. the LHCb upgrade, PANDA, a proposed μ->eee search) will be relying on very fast on-line event reconstruction, including tracking. This in turn requires massive amounts of computing power, which is currently best provided by GPUs. The talk will describe the state of GPU based tracking efforts.

  8. Teaching Elementary Particle Physics: Part I1

    NASA Astrophysics Data System (ADS)

    Hobson, Art

    2011-01-01

    I'll outline suggestions for teaching elementary particle physics, often called high energy physics, in high school or introductory college courses for non-scientists or scientists. Some presentations of this topic simply list the various particles along with their properties, with little overarching structure. Such a laundry list approach is a great way to make a fascinating topic meaningless. Students need a conceptual framework from which to view the elementary particles. That conceptual framework is quantum field theory (QFT). Teachers and students alike tend to quake at this topic, but bear with me. We're talking here about concepts, not technicalities. My approach will be conceptual and suitable for non-scientists and scientists; if mathematical details are added in courses for future scientists, they should be simple and sparse. Introductory students should not be expected to do QFT, but only to understand its concepts. Those concepts take some getting used to, but they are simple and can be understood by any literate person, be she plumber, attorney, musician, or physicist.

  9. Final Report: Particle Physics Research Program

    SciTech Connect

    Karchin, Paul E.

    2011-09-01

    We describe recent progress in accelerator-based experiments in high-energy particle physics and progress in theoretical investigations in particle physics. We also describe future plans in these areas.

  10. Research in Elementary Particle Physics

    SciTech Connect

    White, Andrew Paul; De, Kaushik; Brandt, Andrew; Yu, Jaehoon; Farbin, Amir

    2015-02-02

    This report details the accomplishments and research results for the High Energy Physics Group at the University of Texas at Arlington at the Energy and Intensity Frontiers. For the Energy Frontier we have made fundamental contributions in the search for supersymmetric particles, proposed to explain the stabilization of the mass of the Higgs Boson – the agent giving mass to all known particles. We have also made major contributions to the search for additional Higgs Bosons and to the planning for future searches. This work has been carried out in the context of the ATLAS Experiment at CERN (European Nuclear Research Laboratory) and for which we have made major contributions to computing and data distribution and processing, and have worked to calibrate the detector and prepare upgraded electronics for the future. Our other contribution to the Energy Frontier has been to the International Linear Collider (ILC) project, potentially hosted by Japan, and to the Silicon Detector Concept (SiD) in particular. We have lead the development of the SiD Concept and have worked on a new form of precise energy measurement for particles from the high energy collisions of electrons and positrons at the ILC. For the Intensity Frontier, we have worked to develop the concept of Long Baseline Neutrino Experiment(s) (LBNE) at the Fermi National Accelerator Laboratory. Our contributions to detector development, neutrino beam studies, particle identification, software development will facilitate future studies of the oscillation of one type of neutrino into other type(s), establish the order of the neutrino masses, and, through an innovative new idea, allow us to create a beam of dark matter particles.

  11. Innovative quantum technologies for microgravity fundamental physics and biological research

    NASA Technical Reports Server (NTRS)

    Kierk, I.; Israelsson, U.; Lee, M.

    2001-01-01

    This paper presents a new technology program, within the fundamental physics research program, focusing on four quantum technology areas: quantum atomics, quantum optics, space superconductivity and quantum sensor technology, and quantum fluid based sensor and modeling technology.

  12. Innovative quantum technologies for microgravity fundamental physics and biological research

    NASA Technical Reports Server (NTRS)

    Kierk, I. K.

    2002-01-01

    This paper presents a new technology program, within the fundamental physics, focusing on four quantum technology areas: quantum atomics, quantum optics, space superconductivity and quantum sensor technology, and quantum field based sensor and modeling technology.

  13. Unstable particles in non-relativistic quantum mechanics?

    SciTech Connect

    Hernandez-Coronado, H.

    2011-10-14

    The Schroedinger equation is up-to-a-phase invariant under the Galilei group. This phase leads to the Bargmann's superselection rule, which forbids the existence of the superposition of states with different mass and implies that unstable particles cannot be described consistently in non-relativistic quantum mechanics (NRQM). In this paper we claim that Bargmann's rule neglects physical effects and that a proper description of non-relativistic quantum mechanics requires to take into account this phase through the Extended Galilei group and the definition of its action on spacetime coordinates.

  14. Simulating physical phenomena with a quantum computer

    NASA Astrophysics Data System (ADS)

    Ortiz, Gerardo

    2003-03-01

    In a keynote speech at MIT in 1981 Richard Feynman raised some provocative questions in connection to the exact simulation of physical systems using a special device named a ``quantum computer'' (QC). At the time it was known that deterministic simulations of quantum phenomena in classical computers required a number of resources that scaled exponentially with the number of degrees of freedom, and also that the probabilistic simulation of certain quantum problems were limited by the so-called sign or phase problem, a problem believed to be of exponential complexity. Such a QC was intended to mimick physical processes exactly the same as Nature. Certainly, remarks coming from such an influential figure generated widespread interest in these ideas, and today after 21 years there are still some open questions. What kind of physical phenomena can be simulated with a QC?, How?, and What are its limitations? Addressing and attempting to answer these questions is what this talk is about. Definitively, the goal of physics simulation using controllable quantum systems (``physics imitation'') is to exploit quantum laws to advantage, and thus accomplish efficient imitation. Fundamental is the connection between a quantum computational model and a physical system by transformations of operator algebras. This concept is a necessary one because in Quantum Mechanics each physical system is naturally associated with a language of operators and thus can be considered as a possible model of quantum computation. The remarkable result is that an arbitrary physical system is naturally simulatable by another physical system (or QC) whenever a ``dictionary'' between the two operator algebras exists. I will explain these concepts and address some of Feynman's concerns regarding the simulation of fermionic systems. Finally, I will illustrate the main ideas by imitating simple physical phenomena borrowed from condensed matter physics using quantum algorithms, and present experimental

  15. A proposed physical analog for a quantum probability amplitude

    NASA Astrophysics Data System (ADS)

    Boyd, Jeffrey

    What is the physical analog of a probability amplitude? All quantum mathematics, including quantum information, is built on amplitudes. Every other science uses probabilities; QM alone uses their square root. Why? This question has been asked for a century, but no one previously has proposed an answer. We will present cylindrical helices moving toward a particle source, which particles follow backwards. Consider Feynman's book QED. He speaks of amplitudes moving through space like the hand of a spinning clock. His hand is a complex vector. It traces a cylindrical helix in Cartesian space. The Theory of Elementary Waves changes direction so Feynman's clock faces move toward the particle source. Particles follow amplitudes (quantum waves) backwards. This contradicts wave particle duality. We will present empirical evidence that wave particle duality is wrong about the direction of particles versus waves. This involves a paradigm shift; which are always controversial. We believe that our model is the ONLY proposal ever made for the physical foundations of probability amplitudes. We will show that our ``probability amplitudes'' in physical nature form a Hilbert vector space with adjoints, an inner product and support both linear algebra and Dirac notation.

  16. Hybrid quantum systems with trapped charged particles

    NASA Astrophysics Data System (ADS)

    Kotler, Shlomi; Simmonds, Raymond W.; Leibfried, Dietrich; Wineland, David J.

    2017-02-01

    Trapped charged particles have been at the forefront of quantum information processing (QIP) for a few decades now, with deterministic two-qubit logic gates reaching record fidelities of 99.9 % and single-qubit operations of much higher fidelity. In a hybrid system involving trapped charges, quantum degrees of freedom of macroscopic objects such as bulk acoustic resonators, superconducting circuits, or nanomechanical membranes, couple to the trapped charges and ideally inherit the coherent properties of the charges. The hybrid system therefore implements a "quantum transducer," where the quantum reality (i.e., superpositions and entanglement) of small objects is extended to include the larger object. Although a hybrid quantum system with trapped charges could be valuable both for fundamental research and for QIP applications, no such system exists today. Here we study theoretically the possibilities of coupling the quantum-mechanical motion of a trapped charged particle (e.g., an ion or electron) to the quantum degrees of freedom of superconducting devices, nanomechanical resonators, and quartz bulk acoustic wave resonators. For each case, we estimate the coupling rate between the charged particle and its macroscopic counterpart and compare it to the decoherence rate, i.e., the rate at which quantum superposition decays. A hybrid system can only be considered quantum if the coupling rate significantly exceeds all decoherence rates. Our approach is to examine specific examples by using parameters that are experimentally attainable in the foreseeable future. We conclude that hybrid quantum systems involving a single atomic ion are unfavorable compared with the use of a single electron because the coupling rates between the ion and its counterpart are slower than the expected decoherence rates. A system based on trapped electrons, on the other hand, might have coupling rates that significantly exceed decoherence rates. Moreover, it might have appealing properties such

  17. Non-Perturbative, Unitary Quantum-Particle Scattering Amplitudes from Three-Particle Equations

    SciTech Connect

    Lindesay, James V

    2002-03-19

    We here use our non-perturbative, cluster decomposable relativistic scattering formalism to calculate photon-spinor scattering, including the related particle-antiparticle annihilation amplitude. We start from a three-body system in which the unitary pair interactions contain the kinematic possibility of single quantum exchange and the symmetry properties needed to identify and substitute antiparticles for particles. We extract from it unitary two-particle amplitude for quantum-particle scattering. We verify that we have done this correctly by showing that our calculated photon-spinor amplitude reduces in the weak coupling limit to the usual lowest order, manifestly covariant (QED) result with the correct normalization. That we are able to successfully do this directly demonstrates that renormalizability need not be a fundamental requirement for all physically viable models.

  18. A Synthetic Approach to the Transfer Matrix Method in Classical and Quantum Physics

    ERIC Educational Resources Information Center

    Pujol, O.; Perez, J. P.

    2007-01-01

    The aim of this paper is to propose a synthetic approach to the transfer matrix method in classical and quantum physics. This method is an efficient tool to deal with complicated physical systems of practical importance in geometrical light or charged particle optics, classical electronics, mechanics, electromagnetics and quantum physics. Teaching…

  19. Quantum Random Walks with General Particle States

    NASA Astrophysics Data System (ADS)

    Belton, Alexander C. R.

    2014-06-01

    A convergence theorem is obtained for quantum random walks with particles in an arbitrary normal state. This unifies and extends previous work on repeated-interactions models, including that of Attal and Pautrat (Ann Henri Poincaré 7:59-104 2006) and Belton (J Lond Math Soc 81:412-434, 2010; Commun Math Phys 300:317-329, 2010). When the random-walk generator acts by ampliation and either multiplication or conjugation by a unitary operator, it is shown that the quantum stochastic cocycle which arises in the limit is driven by a unitary process.

  20. Research in theoretical particle physics. Technical progress report, May 1, 1991--April 30, 1992

    SciTech Connect

    McKay, D.W.; Munczek, H.; Ralston, J.

    1992-05-01

    This report discusses the following topics in high energy physics: dynamical symmetry breaking and Schwinger-Dyson equation; consistency bound on the minimal model Higgs mass; tests of physics beyond the standard model; particle astrophysics; the interface between perturbative and non-perturbative QCD; cosmology; anisotropy in quantum networks and integer quantum hall behavior; anomalous color transparency; quantum treatment of solitons; color transparency; quantum stabilization of skyrmions; and casimir effect. (LSP)

  1. Undergraduate computational physics projects on quantum computing

    NASA Astrophysics Data System (ADS)

    Candela, D.

    2015-08-01

    Computational projects on quantum computing suitable for students in a junior-level quantum mechanics course are described. In these projects students write their own programs to simulate quantum computers. Knowledge is assumed of introductory quantum mechanics through the properties of spin 1/2. Initial, more easily programmed projects treat the basics of quantum computation, quantum gates, and Grover's quantum search algorithm. These are followed by more advanced projects to increase the number of qubits and implement Shor's quantum factoring algorithm. The projects can be run on a typical laptop or desktop computer, using most programming languages. Supplementing resources available elsewhere, the projects are presented here in a self-contained format especially suitable for a short computational module for physics students.

  2. Cosmic Rays and Particle Physics

    NASA Astrophysics Data System (ADS)

    Gaisser, Thomas K.; Engel, Ralph; Resconi, Elisa

    2016-06-01

    Preface to the first edition; Preface to the second edition; 1. Cosmic rays; 2. Cosmic ray data; 3. Particle physics; 4. Hadronic interactions and accelerator data; 5. Cascade equations; 6. Atmospheric muons and neutrinos; 7. Neutrino masses and oscillations; 8. Muons and neutrinos underground; 9. Cosmic rays in the Galaxy; 10. Extragalactic propagation of cosmic rays; 11. Astrophysical - rays and neutrinos; 12. Acceleration; 13. Supernovae in the Milky Way; 14. Astrophysical accelerators and beam dumps; 15. Electromagnetic cascades; 16. Extensive air showers; 17. Very high energy cosmic rays; 18. Neutrino astronomy; A.1. Units, constants and definitions; A.2. References to flux measurements; A.3. Particle flux, density, and interaction cross section; A.4. Fundamentals of scattering theory; A.5. Regge amplitude; A.6. Glauber model of nuclear cross sections; A.7. Earth's atmosphere; A.8. Longitudinal development of air showers; A.9. Secondary positrons and electrons; A.10. Liouville's theorem and cosmic ray propagation; A.11. Cosmology and distances measures; A.12. The Hillas splitting algorithm; References; Index.

  3. The dialogue between particle physics and cosmology

    SciTech Connect

    Sadoulet, B.

    1988-04-01

    In the last decade, a very close relationship has developed between particle physics and cosmology. The purpose of these lectures is to introduce particle physicists to the many scientific connections between the two fields. Before entering into the discussion of specific topics, it will first be shown that particle physics and cosmology are completely interdependent. 173 refs., 35 figs., 5 tabs.

  4. A signed particle formulation of non-relativistic quantum mechanics

    SciTech Connect

    Sellier, Jean Michel

    2015-09-15

    A formulation of non-relativistic quantum mechanics in terms of Newtonian particles is presented in the shape of a set of three postulates. In this new theory, quantum systems are described by ensembles of signed particles which behave as field-less classical objects which carry a negative or positive sign and interact with an external potential by means of creation and annihilation events only. This approach is shown to be a generalization of the signed particle Wigner Monte Carlo method which reconstructs the time-dependent Wigner quasi-distribution function of a system and, therefore, the corresponding Schrödinger time-dependent wave-function. Its classical limit is discussed and a physical interpretation, based on experimental evidences coming from quantum tomography, is suggested. Moreover, in order to show the advantages brought by this novel formulation, a straightforward extension to relativistic effects is discussed. To conclude, quantum tunnelling numerical experiments are performed to show the validity of the suggested approach.

  5. Effective Particles in Quantum Field Theory

    NASA Astrophysics Data System (ADS)

    Głazek, Stanisław D.; Trawiński, Arkadiusz P.

    2017-03-01

    The concept of effective particles is introduced in the Minkowski space-time Hamiltonians in quantum field theory using a new kind of the relativistic renormalization group procedure that does not integrate out high-energy modes but instead integrates out the large changes of invariant mass. The new procedure is explained using examples of known interactions. Some applications in phenomenology, including processes measurable in colliders, are briefly presented.

  6. Particle Physics on the Eve of Lhc

    NASA Astrophysics Data System (ADS)

    Studenikin, Alexander I.

    2009-01-01

    Fundamentals of particle physics. The quantum number of color, colored quarks and dynamic models of Hadrons composed of quasifree quarks / V. Matveev, A. Tavkhelidze. Discovery of the color degree of freedom in particle physics: a personal perspective / O. W. Greenberg. The evolution of the concepts of energy, momentum, and mass from Newton and Lomonosov to Einstein and Feynman / L. Okun -- Physics at accelerators and studies in SM and beyond. Search for new physics at LHC (CMS) / N. Krasnikov. Measuring the Higgs Boson(s) at ATLAS / C. Kourkoumelis. Beyond the standard model physics reach of the ATLAS experiment / G. Unel. The status of the International Linear Collider / B. Foster. Review of results of the electron-proton collider HERA / V. Chekelian. Recent results from the Tevatron on CKM matrix elements from Bs oscillations and single top production, and studies of CP violation in Bs Decays / J. P. Fernández. Direct observation of the strange b Barion [symbol] / L. Vertogradov. Search for new physics in rare B Decays at LHCb / V. Egorychev. CKM angle measurements at LHCb / S. Barsuk. Collider searches for extra spatial dimensions and black holes / G. Landsberg -- Neutrino Physics. Results of the MiniBooNE neutrino oscillation experiment / Z. Djurcic. MINOS results and prospects / J. P. Ochoa-Ricoux. The new result of the neutrino magnetic moment measurement in the GEMMA experiment / A. G. Beda ... [et al.]. The Baikal neutrino experiment: status, selected physics results, and perspectives / V. Aynutdinov ... [et al.]. Neutrino telescopes in the deep sea / V. Flaminio. Double beta decay: present status / A. S. Barabash. Beta-beams / C. Volpe. T2K experiment / K. Sakashita. Non-standard neutrino physics probed by Tokai-to-Kamioka-Korea two-detector complex / N. Cipriano Ribeiro ... [et al.]. Sterile neutrinos: from cosmology to the LHC / F. Vannucci. From Cuoricino to Cuore towards the inverted hierarchy region / C. Nones. The MARE experiment: calorimetric

  7. H-theorem in quantum physics

    PubMed Central

    Lesovik, G. B.; Lebedev, A. V.; Sadovskyy, I. A.; Suslov, M. V.; Vinokur, V. M.

    2016-01-01

    Remarkable progress of quantum information theory (QIT) allowed to formulate mathematical theorems for conditions that data-transmitting or data-processing occurs with a non-negative entropy gain. However, relation of these results formulated in terms of entropy gain in quantum channels to temporal evolution of real physical systems is not thoroughly understood. Here we build on the mathematical formalism provided by QIT to formulate the quantum H-theorem in terms of physical observables. We discuss the manifestation of the second law of thermodynamics in quantum physics and uncover special situations where the second law can be violated. We further demonstrate that the typical evolution of energy-isolated quantum systems occurs with non-diminishing entropy. PMID:27616571

  8. H-theorem in quantum physics.

    PubMed

    Lesovik, G B; Lebedev, A V; Sadovskyy, I A; Suslov, M V; Vinokur, V M

    2016-09-12

    Remarkable progress of quantum information theory (QIT) allowed to formulate mathematical theorems for conditions that data-transmitting or data-processing occurs with a non-negative entropy gain. However, relation of these results formulated in terms of entropy gain in quantum channels to temporal evolution of real physical systems is not thoroughly understood. Here we build on the mathematical formalism provided by QIT to formulate the quantum H-theorem in terms of physical observables. We discuss the manifestation of the second law of thermodynamics in quantum physics and uncover special situations where the second law can be violated. We further demonstrate that the typical evolution of energy-isolated quantum systems occurs with non-diminishing entropy.

  9. Quantum optics and frontiers of physics: the third quantum revolution

    NASA Astrophysics Data System (ADS)

    Celi, Alessio; Sanpera, Anna; Ahufinger, Veronica; Lewenstein, Maciej

    2017-01-01

    The year 2015 was the International Year of Light. However, it also marked, the 20th anniversary of the first observation of Bose-Einstein condensation in atomic vapors by Eric Cornell, Carl Wieman and Wolfgang Ketterle. This discovery could be considered as one of the greatest achievements of quantum optics that has triggered an avalanche of further seminal discoveries and achievements. For this reason we devote this essay for the focus issue on ‘Quantum Optics in the International Year of Light’ to the recent revolutionary developments in quantum optics at the frontiers of all physics: atomic physics, molecular physics, condensed matter physics, high energy physics and quantum information science. We follow here the lines of the introduction to our book ‘Ultracold atoms in optical lattices: Simulating quantum many-body systems’ (Lewenstein et al 2012 Ultracold Atoms in Optical Lattices: Simulating Quantum Many-body Systems (Oxford: University Press)), and to a lesser extent the review article M Lewenstein et al (2007 Adv. Phys. 56 243). The book, however, was published in 2012, and many things has happened since then—the present essay is therefore upgraded to include the latest developments.

  10. Multi-physics/scale simulations using particles

    NASA Astrophysics Data System (ADS)

    Koumoutsakos, Petros

    2006-03-01

    Particle simulations of continuum and discrete phenomena can be formulated by following the motion of interacting particles that carry the physical properties of the systems that is being approximated (continuum) or modeled (discrete) by the particles. We identify the common computational characteristics of particle methods and emphasize their key properties that enable the formulation of a novel, systematic framework for multiscale simulations, that can be applicable to the simulation of diverse physical problems. We present novel multiresolution particle methods for continuum (fluid/solid) simulations, using adaptive mesh refinement and wavelets, by relaxing the grid-free character of particle methods and discuss the coupling of scales in continuum-atomistic flow simulations.

  11. Physics: Quantum problems solved through games

    NASA Astrophysics Data System (ADS)

    Maniscalco, Sabrina

    2016-04-01

    Humans are better than computers at performing certain tasks because of their intuition and superior visual processing. Video games are now being used to channel these abilities to solve problems in quantum physics. See Letter p.210

  12. Studies in theoretical particle physics

    SciTech Connect

    Kaplan, D.B.

    1991-07-01

    This proposal focuses on research on three distinct areas of particle physics: (1) Nonperturbative QCD. I tend to continue work on analytic modelling of nonperturbative effects in the strong interactions. I have been investigating the theoretical connection between the nonrelativistic quark model and QCD. The primary motivation has been to understand the experimental observation of nonzero matrix elements involving current strange quarks in ordinary matter -- which in the quark model has no strange quark component. This has led to my present work on understanding constituent (quark model) quarks as collective excitations of QCD degrees of freedom. (2) Weak Scale Baryogenesis. A continuation of work on baryogenesis in the early universe from weak interactions. In particular, an investigation of baryogenesis occurring during the weak phase transition through anomalous baryon violating processes in the standard model of weak interactions. (3) Flavor and Compositeness. Further investigation of a new mechanism that I recently discovered for dynamical mass generation for fermions, which naturally leads to a family hierarchy structure. A discussion of recent past work is found in the next section, followed by an outline of the proposed research. A recent publication from each of these three areas is attached to this proposal.

  13. Computer Visualization of Many-Particle Quantum Dynamics

    SciTech Connect

    Ozhigov, A. Y.

    2009-03-10

    In this paper I show the importance of computer visualization in researching of many-particle quantum dynamics. Such a visualization becomes an indispensable illustrative tool for understanding the behavior of dynamic swarm-based quantum systems. It is also an important component of the corresponding simulation framework, and can simplify the studies of underlying algorithms for multi-particle quantum systems.

  14. Topics in elementary particle physics

    NASA Astrophysics Data System (ADS)

    Jin, Xiang

    The author of this thesis discusses two topics in elementary particle physics: n-ary algebras and their applications to M-theory (Part I), and functional evolution and Renormalization Group flows (Part II). In part I, Lie algebra is extended to four different n-ary algebraic structure: generalized Lie algebra, Filippov algebra, Nambu algebra and Nambu-Poisson tensor; though there are still many other n-ary algebras. A natural property of Generalized Lie algebras — the Bremner identity, is studied, and proved with a totally different method from its original version. We extend Bremner identity to n-bracket cases, where n is an arbitrary odd integer. Filippov algebras do not focus on associativity, and are defined by the Fundamental identity. We add associativity to Filippov algebras, and give examples of how to construct Filippov algebras from su(2), bosonic oscillator, Virasoro algebra. We try to include fermionic charges into the ternary Virasoro-Witt algebra, but the attempt fails because fermionic charges keep generating new charges that make the algebra not closed. We also study the Bremner identity restriction on Nambu algebras and Nambu-Poisson tensors. So far, the only example 3-algebra being used in physics is the BLG model with 3-algebra A4, describing two M2-branes interactions. Its extension with Nambu algebra, BLG-NB model, is believed to describe infinite M2-branes condensation. Also, there is another propose for M2-brane interactions, the ABJM model, which is constructed by ordinary Lie algebra. We compare the symmetry properties between them, and discuss the possible approaches to include these three models into a grand unification theory. In Part II, we give an approximate solution for Schroeder's equations, based on series and conjugation methods. We use the logistic map as an example, and demonstrate that this approximate

  15. Two-particle bosonic-fermionic quantum walk via integrated photonics.

    PubMed

    Sansoni, Linda; Sciarrino, Fabio; Vallone, Giuseppe; Mataloni, Paolo; Crespi, Andrea; Ramponi, Roberta; Osellame, Roberto

    2012-01-06

    Quantum walk represents one of the most promising resources for the simulation of physical quantum systems, and has also emerged as an alternative to the standard circuit model for quantum computing. Here we investigate how the particle statistics, either bosonic or fermionic, influences a two-particle discrete quantum walk. Such an experiment has been realized by exploiting polarization entanglement to simulate the bunching-antibunching feature of noninteracting bosons and fermions. To this scope a novel three-dimensional geometry for the waveguide circuit is introduced, which allows accurate polarization independent behavior, maintaining remarkable control on both phase and balancement.

  16. Quarked!--Adventures in Particle Physics Education

    ERIC Educational Resources Information Center

    MacDonald, Teresa; Bean, Alice

    2009-01-01

    Particle physics is a subject that can send shivers down the spines of students and educators alike--with visions of long mathematical equations and inscrutable ideas. This perception, along with a full curriculum, often leaves this topic the road less traveled until the latter years of school. Particle physics, including quarks, is typically not…

  17. Particle Physics: From School to University.

    ERIC Educational Resources Information Center

    Barlow, Roger

    1992-01-01

    Discusses the teaching of particle physics as part of the A-level physics course in British secondary schools. Utilizes the quark model of hadrons and the conceptual kinematics of particle collisions, as examples, to demonstrate practical instructional possibilities in relation to student expectations. (JJK)

  18. Teaching Elementary Particle Physics: Part I

    ERIC Educational Resources Information Center

    Hobson, Art

    2011-01-01

    I'll outline suggestions for teaching elementary particle physics, often called "high energy physics," in high school or introductory college courses for non-scientists or scientists. Some presentations of this topic simply list the various particles along with their properties, with little overarching structure. Such a laundry list approach is a…

  19. On foundation of quantum physics

    SciTech Connect

    Solov'ev, E. A.

    2009-05-15

    Some aspects of the interpretation of quantum theory are discussed. It is emphasized that quantum theory is formulated in the Cartesian coordinate system; in other coordinates the result obtained with the help of the Hamiltonian formalism and commutator relations between 'canonically conjugated' coordinate and momentum operators leads to a wrong version of quantum mechanics. The origin of time is analyzed by the example of atomic collision theory in detail; it is shown that the time-dependent Schroedinger equation is meaningless since in the high-impact-energy limit it transforms into an equation with two time-like variables. Following the Einstein-Rozen-Podolsky experiment and Bell's inequality, the wave function is interpreted as an actual field of information in the elementary form. The concept 'measurement' is also discussed.

  20. Differential evolution for many-particle adaptive quantum metrology.

    PubMed

    Lovett, Neil B; Crosnier, Cécile; Perarnau-Llobet, Martí; Sanders, Barry C

    2013-05-31

    We devise powerful algorithms based on differential evolution for adaptive many-particle quantum metrology. Our new approach delivers adaptive quantum metrology policies for feedback control that are orders-of-magnitude more efficient and surpass the few-dozen-particle limitation arising in methods based on particle-swarm optimization. We apply our method to the binary-decision-tree model for quantum-enhanced phase estimation as well as to a new problem: a decision tree for adaptive estimation of the unknown bias of a quantum coin in a quantum walk and show how this latter case can be realized experimentally.

  1. The Physical Renormalization of Quantum Field Theories

    SciTech Connect

    Binger, Michael William.; /Stanford U., Phys. Dept. /SLAC

    2007-02-20

    The profound revolutions in particle physics likely to emerge from current and future experiments motivates an improved understanding of the precise predictions of the Standard Model and new physics models. Higher order predictions in quantum field theories inevitably requires the renormalization procedure, which makes sensible predictions out of the naively divergent results of perturbation theory. Thus, a robust understanding of renormalization is crucial for identifying and interpreting the possible discovery of new physics. The results of this thesis represent a broad set of investigations in to the nature of renormalization. The author begins by motivating a more physical approach to renormalization based on gauge-invariant Green's functions. The resulting effective charges are first applied to gauge coupling unification. This approach provides an elegant formalism for understanding all threshold corrections, and the gauge couplings unify in a more physical manner compared to the usual methods. Next, the gauge-invariant three-gluon vertex is studied in detail, revealing an interesting and rich structure. The effective coupling for the three-gluon vertex, {alpha}(k{sub 1}{sup 2}, k{sub 2}{sup 2}, k{sub 3}{sup 2}), depends on three momentum scales and gives rise to an effective scale Q{sub eff}{sup 2}(k{sub 1}{sup 2}, k{sub 2}{sup 2}, k{sub 3}{sup 2}) which governs the (sometimes surprising) behavior of the vertex. The effects of nonzero internal masses are important and have a complicated threshold and pseudo-threshold structure. The pinch-technique effective charge is also calculated to two-loops and several applications are discussed. The Higgs boson mass in Split Supersymmetry is calculated to two-loops, including all one-loop threshold effects, leading to a downward shift in the Higgs mass of a few GeV. Finally, the author discusses some ideas regarding the overall structure of perturbation theory. This thesis lays the foundation for a comprehensive multi

  2. Standard Model of Particle Physics--a health physics perspective.

    PubMed

    Bevelacqua, J J

    2010-11-01

    The Standard Model of Particle Physics is reviewed with an emphasis on its relationship to the physics supporting the health physics profession. Concepts important to health physics are emphasized and specific applications are presented. The capability of the Standard Model to provide health physics relevant information is illustrated with application of conservation laws to neutron and muon decay and in the calculation of the neutron mean lifetime.

  3. Toward a physical theory of quantum cognition.

    PubMed

    Takahashi, Taiki

    2014-01-01

    Recently, mathematical models based on quantum formalism have been developed in cognitive science. The target articles in this special issue of Topics in Cognitive Science clearly illustrate how quantum theoretical formalism can account for various aspects of human judgment and decision making in a quantitatively and mathematically rigorous manner. In this commentary, we show how future studies in quantum cognition and decision making should be developed to establish theoretical foundations based on physical theory, by introducing Taketani's three-stage theory of the development of science. Also, implications for neuroeconomics (another rapidly evolving approach to human judgment and decision making) are discussed.

  4. Charged particle therapy: the physics of interaction.

    PubMed

    Lomax, Antony J

    2009-01-01

    Particle therapy has a long and distinguished history with more than 50,000 patients having been treated, mainly with high-energy proton therapy. Particularly, for proton therapy, there is an increasing interest in exploiting the physical characteristics of charged particles for further improving the potential of radiation therapy. In this article, we review the most important interactions of charged particles with matter and describe the basic physical principles that underlie why particle beams behave the way they do and why such a behavior could bring many benefits in radiation therapy.

  5. The Particle inside a Ring: A Two-Dimensional Quantum Problem Visualized by Scanning Tunneling Microscopy

    ERIC Educational Resources Information Center

    Ellison, Mark D.

    2008-01-01

    The one-dimensional particle-in-a-box model used to introduce quantum mechanics to students suffers from a tenuous connection to a real physical system. This article presents a two-dimensional model, the particle confined within a ring, that directly corresponds to observations of surface electrons in a metal trapped inside a circular barrier.…

  6. Being qua becoming: Aristotle's "Metaphysics", quantum physics, and Process Philosophy

    NASA Astrophysics Data System (ADS)

    Johnson, David Kelley

    In Aristotle's First Philosophy, science and philosophy were partners, but with the rise of empiricism, went their separate ways. Metaphysics combined the rational and irrational (i.e. final cause/unmoved mover) elements of existence to equate being with substance, postulating prime matter as pure potential that was actuated by form to create everything. Modern science reveres pure reason and postulates its theory of being by a rigorous scientific methodology. The Standard Model defines matter as energy formed into fundamental particles via forces contained in fields. Science has proved Aristotle's universe wrong in many ways, but as physics delves deeper into the quantum world, empiricism is reaching its limits concerning fundamental questions of existence. To achieve its avowed mission of explaining existence completely, physics must reunite with philosophy in a metascience modeled on the First Philosophy of Aristotle. One theory of being that integrates quantum physics and metaphysics is Process Philosophy.

  7. Quantum physics of classical waves in plasma

    NASA Astrophysics Data System (ADS)

    Dodin, I. Y.

    2012-10-01

    The Lagrangian approach to plasma wave physics is extended to a universal nonlinear theory which yields generic equations invariant with respect to the wave nature. The traditional understanding of waves as solutions of the Maxwell-Vlasov system is abandoned. Oscillations are rather treated as physical entities, namely, abstract vectors |ψ> in a specific Hilbert space. The invariant product <ψ|ψ> is the total action and has the sign of the oscillation energy. The action density is then an operator. Projections of the corresponding operator equation generate assorted wave kinetic equations; the nonlinear Wigner-Moyal equation is just one example and, in fact, may be more delicate than commonly assumed. The linear adiabatic limit of this classical theory leads to quantum mechanics in its general form. The action conservation theorem, together with its avatars such as Manley-Rowe relations, then becomes manifest and in partial equilibrium can modify statistical properties of plasma fluctuations. In the quasi-monochromatic limit geometrical optics (GO) is recovered and can as well be understood as a particular field theory in its own right. For linear waves, the energy-momentum equations, in both canonical and (often) kinetic form, then follow automatically, even without a reference to electromagnetism. Yet for waves in plasma the general GO Lagrangian is also derived explicitly, in terms of single-particle oscillation-center Hamiltonians. Applications to various plasma waves are then discussed with an emphasis on the advantages of an abstract theory. Specifically covered are nonlinear dispersion, dynamics, and stability of BGK modes, and also other wave transformations in laboratory and cosmological plasmas.

  8. Certified randomness in quantum physics.

    PubMed

    Acín, Antonio; Masanes, Lluis

    2016-12-07

    The concept of randomness plays an important part in many disciplines. On the one hand, the question of whether random processes exist is fundamental for our understanding of nature. On the other, randomness is a resource for cryptography, algorithms and simulations. Standard methods for generating randomness rely on assumptions about the devices that are often not valid in practice. However, quantum technologies enable new methods for generating certified randomness, based on the violation of Bell inequalities. These methods are referred to as device-independent because they do not rely on any modelling of the devices. Here we review efforts to design device-independent randomness generators and the associated challenges.

  9. Certified randomness in quantum physics

    NASA Astrophysics Data System (ADS)

    Acín, Antonio; Masanes, Lluis

    2016-12-01

    The concept of randomness plays an important part in many disciplines. On the one hand, the question of whether random processes exist is fundamental for our understanding of nature. On the other, randomness is a resource for cryptography, algorithms and simulations. Standard methods for generating randomness rely on assumptions about the devices that are often not valid in practice. However, quantum technologies enable new methods for generating certified randomness, based on the violation of Bell inequalities. These methods are referred to as device-independent because they do not rely on any modelling of the devices. Here we review efforts to design device-independent randomness generators and the associated challenges.

  10. Quantum chaos and thermalization in isolated systems of interacting particles

    NASA Astrophysics Data System (ADS)

    Borgonovi, F.; Izrailev, F. M.; Santos, L. F.; Zelevinsky, V. G.

    2016-04-01

    This review is devoted to the problem of thermalization in a small isolated conglomerate of interacting constituents. A variety of physically important systems of intensive current interest belong to this category: complex atoms, molecules (including biological molecules), nuclei, small devices of condensed matter and quantum optics on nano- and micro-scale, cold atoms in optical lattices, ion traps. Physical implementations of quantum computers, where there are many interacting qubits, also fall into this group. Statistical regularities come into play through inter-particle interactions, which have two fundamental components: mean field, that along with external conditions, forms the regular component of the dynamics, and residual interactions responsible for the complex structure of the actual stationary states. At sufficiently high level density, the stationary states become exceedingly complicated superpositions of simple quasiparticle excitations. At this stage, regularities typical of quantum chaos emerge and bring in signatures of thermalization. We describe all the stages and the results of the processes leading to thermalization, using analytical and massive numerical examples for realistic atomic, nuclear, and spin systems, as well as for models with random parameters. The structure of stationary states, strength functions of simple configurations, and concepts of entropy and temperature in application to isolated mesoscopic systems are discussed in detail. We conclude with a schematic discussion of the time evolution of such systems to equilibrium.

  11. A quantum particle in a box with moving walls

    NASA Astrophysics Data System (ADS)

    Di Martino, Sara; Anzà, Fabio; Facchi, Paolo; Kossakowski, Andrzej; Marmo, Giuseppe; Messina, Antonino; Militello, Benedetto; Pascazio, Saverio

    2013-09-01

    We analyze the non-relativistic problem of a quantum particle that bounces back and forth between two moving walls. We recast this problem into the equivalent one of a quantum particle in a fixed box whose dynamics is governed by an appropriate time-dependent Schrödinger operator.

  12. Switchable particle statistics with an embedding quantum simulator

    NASA Astrophysics Data System (ADS)

    Cheng, Xiao-Hang; Arrazola, Iñigo; Pedernales, Julen S.; Lamata, Lucas; Chen, Xi; Solano, Enrique

    2017-02-01

    We propose the implementation of a switch of particle statistics with an embedding quantum simulator. By encoding both Bose-Einstein and Fermi-Dirac statistics into an enlarged Hilbert space, the statistics of the simulated quantum particles may be changed in situ during the time evolution, from bosons to fermions and from fermions to bosons, as many times as desired before a measurement is performed. We illustrate our proposal with few-qubit examples, although the protocol is straightforwardly extendable to larger numbers of particles. This proposal can be implemented on different quantum platforms such as trapped ions, quantum photonics, and superconducting circuits, among others. The possibility to implement permutation symmetrization and antisymmetrization of quantum particles enhances the toolbox of quantum simulations for unphysical operations as well as for symmetry transformations.

  13. Particle transport and deposition: basic physics of particle kinetics.

    PubMed

    Tsuda, Akira; Henry, Frank S; Butler, James P

    2013-10-01

    The human body interacts with the environment in many different ways. The lungs interact with the external environment through breathing. The enormously large surface area of the lung with its extremely thin air-blood barrier is exposed to particles suspended in the inhaled air. The particle-lung interaction may cause deleterious effects on health if the inhaled pollutant aerosols are toxic. Conversely, this interaction can be beneficial for disease treatment if the inhaled particles are therapeutic aerosolized drugs. In either case, an accurate estimation of dose and sites of deposition in the respiratory tract is fundamental to understanding subsequent biological response, and the basic physics of particle motion and engineering knowledge needed to understand these subjects is the topic of this article. A large portion of this article deals with three fundamental areas necessary to the understanding of particle transport and deposition in the respiratory tract. These are: (i) the physical characteristics of particles, (ii) particle behavior in gas flow, and (iii) gas-flow patterns in the respiratory tract. Other areas, such as particle transport in the developing lung and in the diseased lung are also considered. The article concludes with a summary and a brief discussion of areas of future research.

  14. Particle transport and deposition: basic physics of particle kinetics

    PubMed Central

    Tsuda, Akira; Henry, Frank S.; Butler, James P.

    2015-01-01

    The human body interacts with the environment in many different ways. The lungs interact with the external environment through breathing. The enormously large surface area of the lung with its extremely thin air-blood barrier is exposed to particles suspended in the inhaled air. Whereas the particle-lung interaction may cause deleterious effects on health if the inhaled pollutant aerosols are toxic, this interaction can be beneficial for disease treatment if the inhaled particles are therapeutic aerosolized drug. In either case, an accurate estimation of dose and sites of deposition in the respiratory tract is fundamental to understanding subsequent biological response, and the basic physics of particle motion and engineering knowledge needed to understand these subjects is the topic of this chapter. A large portion of this chapter deals with three fundamental areas necessary to the understanding of particle transport and deposition in the respiratory tract. These are: 1) the physical characteristics of particles, 2) particle behavior in gas flow, and 3) gas flow patterns in the respiratory tract. Other areas, such as particle transport in the developing lung and in the diseased lung are also considered. The chapter concludes with a summary and a brief discussion of areas of future research. PMID:24265235

  15. Motivating quantum field theory: the boosted particle in a box

    NASA Astrophysics Data System (ADS)

    Vutha, Amar C.

    2013-07-01

    It is a maxim often stated, yet rarely illustrated, that the combination of special relativity and quantum mechanics necessarily leads to quantum field theory. An elementary illustration is provided using the familiar particle in a box, boosted to relativistic speeds. It is shown that quantum fluctuations of momentum lead to energy fluctuations, which are inexplicable without a framework that endows the vacuum with dynamical degrees of freedom and allows particle creation/annihilation.

  16. Symmetry and Natural Quantum Structures for Three-Particles in One-Dimension

    NASA Astrophysics Data System (ADS)

    Harshman, N. L.

    How symmetries induce natural and useful quantum structures is explored by looking at models of three interacting particles in onedimension. Models with three interacting particles manifest the nearly full spectrum of possibilities for dynamical systems. The chapter demonstrates that the related but distinct notions of integrability, separability, and solvability identify useful collective observables for Hamiltonians with sufficient symmetry. In turn, these observables induce tensor product structures on the Hilbert space that may be especially useful for storing and processing quantum information and may provide some deeper guidance to interpretation and phenomenology of quantum fewbody physics.

  17. Holism, physical theories and quantum mechanics

    NASA Astrophysics Data System (ADS)

    Seevinck, M. P.

    Motivated by the question what it is that makes quantum mechanics a holistic theory (if so), I try to define for general physical theories what we mean by `holism'. For this purpose I propose an epistemological criterion to decide whether or not a physical theory is holistic, namely: a physical theory is holistic if and only if it is impossible in principle to infer the global properties, as assigned in the theory, by local resources available to an agent. I propose that these resources include at least all local operations and classical communication. This approach is contrasted with the well-known approaches to holism in terms of supervenience. The criterion for holism proposed here involves a shift in emphasis from ontology to epistemology. I apply this epistemological criterion to classical physics and Bohmian mechanics as represented on a phase and configuration space respectively, and for quantum mechanics (in the orthodox interpretation) using the formalism of general quantum operations as completely positive trace non-increasing maps. Furthermore, I provide an interesting example from which one can conclude that quantum mechanics is holistic in the above mentioned sense, although, perhaps surprisingly, no entanglement is needed.

  18. Research on elementary particle physics

    SciTech Connect

    Holloway, L.E.; O'Halloran, T.A.

    1992-05-01

    This report describes the activities of the University of Illinois Experimental High Energy Physics Group. The physicists in the University of Illinois High Energy Physics Group are engaged in a wide variety of experiments at current and future accelerator laboratories. These include: (1) The CDF experiment at the Fermilab Tevetron p{bar p} collider. (2) Design and developmental work for the SDC group at SSCL. (3) Experiments at the wide band photon beam at Fermilab. (4) The SLD experiment at SLAC and design studies for a {tau}-charm factor. (5) CP violation experiments at Fermilab. (6) The HiRes cosmic ray experiment at Dugway Proving Grounds, Utah. (7) Computational facilities. (8) Electronics systems development.

  19. Theoretical particle physics, Task A

    SciTech Connect

    Not Available

    1991-07-01

    This report briefly discusses the following topics: The Spin Structure of the Nucleon; Solitons and Discrete Symmetries; Baryon Chiral Perturbation Theory; Constituent Quarks as Collective Excitations; Kaon Condensation; Limits on Neutrino Masses; The 17 KeV Neutrino and Majoron Models; The Strong CP Problem; Renormalization of the CP Violating {Theta} Parameter; Weak Scale Baryogenesis; Chiral Charge in Finite Temperature QED; The Heavy Higgs Mass Bound; The Heavy Top Quark Bound; The Heavy Top Quark Condensate; The Heavy Top Quark Vacuum Instability; Phase Diagram of the Lattice Higgs-Yukawa Model; Anomalies and the Standard Model on the Lattice; Constraint Effective Potential in a Finite Box; Resonance Picture in a Finite Box; Fractal Dimension of Critical Clusters; Goldstone Bosons at Finite Temperature; Cluster Algorithms and Scaling in CP(N) Models; Rare Decay Modes of the Z{degrees} Vector Boson; Parity-Odd Spin-Dependent Structure Functions; Radiative Corrections, Top Mass and LEP Data; Supersymmetric Model with the Higgs as a Lepton; Chiral Change Oscillation in the Schwinger Model; Electric Dipole Moment of the Neutron; DOE Grand Challenge Program; and Lattice Quantum Electrodynamics.

  20. Symmetry, conservation laws, and theoretical particle physics

    NASA Astrophysics Data System (ADS)

    Krumins, Andris Visvaldis

    In this work, we trace the role of symmetry throughout the history of theoretical particle physics, paying particular attention to the role of group theory, the formal mathematics of symmetry. After an analysis of the role of conservation laws and invariance in the theory of general relativity, we move on to Weyl's gauge theory of 1918, which was developed within the context of general relativity as an attempt to unify gravitation and electromagnetism. Weyl was trying to exploit an invariance of scale, and although his theory was experimentally refuted, it provided a formulation of the conservation of charge. After the advent of quantum mechanics, gauge theory was reinterpreted by London as an invariance of the wave-function. Weyl and Wigner studied group theory in the context of quantum mechanics, but the broadness of its application had yet to be appreciated. Symmetry was soon exploited in the nuclear interactions, however, and we examine the events leading to the discovery of SU(2) of isotopic spin. We analyze how the discovery of strangeness was linked to the generalization of SU(2) to SU(3), and also how it led to a differentiation between the strong interactions, which conserve isotopic spin and strangeness, and the weak interactions, which violate these conservation laws, along with the conservation of parity. Yang and Mills were impressed with gauge invariance, and in 1954, they took the bold step of imposing it upon the Lagrangian of the strong interactions, forcing the introduction of three new gauge fields. There was a problem, however, because although the short-range of the strong interactions implied that these gauge bosons should be massive, they needed to be massless in order to preserve gauge invariance. In addition, efforts were made to extend Yang-Mills theory to the weak interactions, but they also faced the same zero-mass problem. This problem was finally solved in 1967, when Weinberg and Salam showed how gauge boson masses could be generated

  1. Small Particle May Answer Large Physics Questions

    SciTech Connect

    Hazi, A

    2005-09-20

    In one of those interesting intersections of particle physics, astrophysics, and cosmology, scientists from Lawrence Livermore National Laboratory, the University of California at Berkeley (UCB), the University of Florida (UF), and the National Radio Astronomy Observatory (NRAO) have joined together to try to pin down an elusive particle. This particle, called the axion, if it is found to exist and is not just a hypothesis, would be a long-sought relic from the first fractional second of the birth of the universe and one of the most weakly interacting particles known. Experimental verification of the existence of the axion would not only help ''balance the budget'' for the missing mass of the universe but also clear up one of the thorniest issues in particle physics.

  2. On the photoelectric quantum yield of small dust particles

    NASA Astrophysics Data System (ADS)

    Kimura, Hiroshi

    2016-07-01

    Photoelectron emission is crucial to electric charging of dust particles around main-sequence stars and gas heating in various dusty environments. An estimate of the photoelectric processes contains an ill-defined parameter called the photoelectric quantum yield, which is the total number of electrons ejected from a dust particle per absorbed photon. Here we revisit the so-called small particle effect of photoelectron emission and provide an analytical model to estimate photoelectric quantum yields of small dust particles in sizes down to nanometers. We show that the small particle effect elevates the photoelectric quantum yields of nanoparticles up to by a factor of 103 for carbon, water ice, and organics, and a factor of 102 for silicate, silicon carbide, and iron. We conclude the surface curvature of the particles is a quantity of great importance to the small particle effect, unless the particles are submicrometers in radius or larger.

  3. Physics on the boundary between classical and quantum mechanics

    NASA Astrophysics Data System (ADS)

    't Hooft, Gerard

    2014-04-01

    Nature's laws in the domain where relativistic effects, gravitational effects and quantum effects are all comparatively strong are far from understood. This domain is called the Planck scale. Conceivably, a theory can be constructed where the quantum nature of phenomena at such scales can be attributed to something fundamentally simpler. However, arguments that quantum mechanics cannot be explained in terms of any classical theory using only classical logic seem to be based on sound mathematical considerations: there can't be physical laws that require "conspiracy". It may therefore be surprising that there are several explicit quantum systems where these considerations apparently do not apply. In the lecture we will show several such counterexamples. These are quantum models that do have a classical origin. The most curious of these models is superstring theory. This theory is often portrayed as to underly the quantum field theory of the subatomic particles, including the "Standard Model". So now the question is asked: how can this model feature "conspiracy", and how bad is that? Is there conspiracy in the vacuum fluctuations?

  4. Quantum physics reimagined for the general public

    NASA Astrophysics Data System (ADS)

    Bobroff, Julien

    2015-03-01

    Quantum Physics has always been a challenging issue for outreach. It is invisible, non-intuitive and written in sophisticated mathematics. In our ``Physics Reimagined'' research group, we explore new ways to present that field to the general public. Our approach is to develop close collaborations between physicists and designers or graphic artists. By developing this new kind of dialogue, we seek to find new ways to present complex phenomena and recent research topics to the public at large. For example, we created with web-illustrators a series of 3D animations about basic quantum laws and research topics (graphene, Bose-Einstein condensation, decoherence, pump-probe techniques, ARPES...). We collaborated with designers to develop original setups, from quantum wave animated models or foldings to a superconducting circus with levitating animals. With illustrators, we produced exhibits, comic strips or postcards displaying the physicists in their labs, either famous ones or even our own colleagues in their daily life as researchers. With artists, we recently made a stop-motion picture to explain in an esthetic way the process of discovery and scientific publication. We will discuss how these new types of outreach projects allowed us to engage the public with modern physics both on a scientific and cultural level and how the concepts and process can easily be replicated and expanded by other physicists. We are at the precise time when creative tools, interfaces, and ways of sharing and learning are rapidly evolving (wikipedia, MOOCs, smartphones...). If scientists don't step forward to employ these tools and develop new resources, other people will, and the integrity of the science and underlying character of research risks being compromised. All our productions are free to use and can be downloaded at www.PhysicsReimagined.com (for 3D quantum videos, specific link: www.QuantumMadeSimple.com) This work benefited from the support of the Chair ``Physics Reimagined

  5. Nuclear and Particle Physics Simulations: The Consortium of Upper-Level Physics Software

    NASA Astrophysics Data System (ADS)

    Bigelow, Roberta; Moloney, Michael J.; Philpott, John; Rothberg, Joseph

    1995-06-01

    The Consortium for Upper Level Physics Software (CUPS) has developed a comprehensive series of Nine Book/Software packages that Wiley will publish in FY `95 and `96. CUPS is an international group of 27 physicists, all with extensive backgrounds in the research, teaching, and development of instructional software. The project is being supported by the National Science Foundation (PHY-9014548), and it has received other support from the IBM Corp., Apple Computer Corp., and George Mason University. The Simulations being developed are: Astrophysics, Classical Mechanics, Electricity & Magnetism, Modern Physics, Nuclear and Particle Physics, Quantum Mechanics, Solid State, Thermal and Statistical, and Wave and Optics.

  6. What is a Particle in Classical Physics? A Wave?

    NASA Astrophysics Data System (ADS)

    Mickens, Ronald E.

    2005-11-01

    The concepts of ``particle" and ``wave" play important roles in quantum mechanics in that a given microscopic system can, under the proper circumstances, display properties of each.ootnotetextA Messiah, Quantum Mechanics, Vols. I and II (Wiley, 1961). However, these categories have their genesis in classical mechanicsootnotetextH. Goldstein, Classical Mechanics (Addison-Wesley, 1980, 2nd edition). and we must turn to this area to understand what they mean. In particular, it must be clearly understood that these concepts are idealistic representations of physical phenomena and, as a consequence, each may not correspond to any actual physical system. We discuss the definition of ``particle'' from the perspective of how it has been defined in standard textbooks and carry out a similar analysis for the notion of ``wave.'' We then define ``particle'' and ``wave'' within the context of classical mechanics by means of their respective equations of motion. The general (tentative) conclusion is that within the framework of classical mechanics the concepts of ``particle'' and ``wave'' systems may be unambiguously defined.

  7. Elementary particle physics at the University of Florida

    SciTech Connect

    Not Available

    1991-12-01

    This report discusses research in the following areas: theoretical elementary particle physics; experimental elementary particle physics; axion project; SSC detector development; and computer acquisition. (LSP).

  8. Plato's TIMAIOσ (TIMAEUS) and Modern Particle Physics

    NASA Astrophysics Data System (ADS)

    Machleidt, Ruprecht

    2005-04-01

    It is generally known that the question, ``What are the smallest particles (elementary particles) that all matter is made from?'', was posed already in the antiquity. The Greek natural philosophers Leucippus and Democritus were the first to suggest that all matter was made from atoms. Therefore, most people perceive them as the ancient fathers of elementary particle physics. It will be the purpose of my contribution to point out that this perception is wrong. Modern particle physics is not just a primitive atomism. More important than the materialistic particles are the underlying symmetries (e. g., SU(3) and SU(6)). A similar idea was first advanced by Plato in his dialog TIMAIOσ (Latin translation: TIMAEUS): Geometric symmetries generate the materialistic particles from a few even more elementary items. Plato's vision is amazingly close to the ideas of modern particle physics. This fact, which is unfortunately little known, has been pointed out repeatedly by Heisenberg (see, e. g., Werner Heisenberg, Across the Frontiers, Harper & Row, New York, 1974).

  9. Quantum correlations of identical particles subject to classical environmental noise

    NASA Astrophysics Data System (ADS)

    Beggi, Andrea; Buscemi, Fabrizio; Bordone, Paolo

    2016-09-01

    In this work, we propose a measure for the quantum discord of indistinguishable particles, based on the definition of entanglement of particles given in Wiseman and Vaccaro (Phys Rev Lett 91:097902, 2003. doi: 10.1103/PhysRevLett.91.097902). This discord of particles is then used to evaluate the quantum correlations in a system of two identical bosons (fermions), where the particles perform a quantum random walk described by the Hubbard Hamiltonian in a 1D lattice. The dynamics of the particles is either unperturbed or subject to a classical environmental noise—such as random telegraph, pink or brown noise. The observed results are consistent with those for the entanglement of particles, and we observe that on-site interaction between particles have an important protective effect on correlations against the decoherence of the system.

  10. Flavor Democracy in Particle Physics

    NASA Astrophysics Data System (ADS)

    Sultansoy, Saleh

    2007-04-01

    The flavor democracy hypothesis (or, in other words, democratic mass matrix approach) was introduced in seventies taking in mind three Standard Model (SM) families. Later, this idea was disfavored by the large value of the t-quark mass. In nineties the hypothesis was revisited assuming that extra SM families exist. According to flavor democracy the fourth SM family should exist and there are serious arguments disfavoring the fifth SM family. The fourth SM family quarks lead to essential enhancement of the Higgs boson production cross-section at hadron colliders and the Tevatron can discover the Higgs boson before the LHC, if it mass is between 140 and 200 GeV. Then, one can handle ``massless'' Dirac neutrinos without see-saw mechanism. Concerning BSM physics, flavor democracy leads to several consequences: tanβ ~ mt/mb ~ 40 if there are three MSSM families; super-partner of the right-handed neutrino can be the LSP; relatively light E(6)-inspired isosinglet quark etc. Finally, flavor democracy may give opportunity to handle ``massless'' composite objects within preonic models.

  11. Research in Theoretical Particle Physics

    SciTech Connect

    Feldman, Hume A; Marfatia, Danny

    2014-09-24

    This document is the final report on activity supported under DOE Grant Number DE-FG02-13ER42024. The report covers the period July 15, 2013 – March 31, 2014. Faculty supported by the grant during the period were Danny Marfatia (1.0 FTE) and Hume Feldman (1% FTE). The grant partly supported University of Hawaii students, David Yaylali and Keita Fukushima, who are supervised by Jason Kumar. Both students are expected to graduate with Ph.D. degrees in 2014. Yaylali will be joining the University of Arizona theory group in Fall 2014 with a 3-year postdoctoral appointment under Keith Dienes. The group’s research covered topics subsumed under the Energy Frontier, the Intensity Frontier, and the Cosmic Frontier. Many theoretical results related to the Standard Model and models of new physics were published during the reporting period. The report contains brief project descriptions in Section 1. Sections 2 and 3 lists published and submitted work, respectively. Sections 4 and 5 summarize group activity including conferences, workshops and professional presentations.

  12. Flavor Democracy in Particle Physics

    SciTech Connect

    Sultansoy, Saleh

    2007-04-23

    The flavor democracy hypothesis (or, in other words, democratic mass matrix approach) was introduced in seventies taking in mind three Standard Model (SM) families. Later, this idea was disfavored by the large value of the t-quark mass. In nineties the hypothesis was revisited assuming that extra SM families exist. According to flavor democracy the fourth SM family should exist and there are serious arguments disfavoring the fifth SM family. The fourth SM family quarks lead to essential enhancement of the Higgs boson production cross-section at hadron colliders and the Tevatron can discover the Higgs boson before the LHC, if it mass is between 140 and 200 GeV. Then, one can handle 'massless' Dirac neutrinos without see-saw mechanism. Concerning BSM physics, flavor democracy leads to several consequences: tan{beta} {approx_equal} mt/mb {approx_equal} 40 if there are three MSSM families; super-partner of the right-handed neutrino can be the LSP; relatively light E(6)-inspired isosinglet quark etc. Finally, flavor democracy may give opportunity to handle ''massless'' composite objects within preonic models.

  13. Basics of particle therapy I: physics.

    PubMed

    Park, Seo Hyun; Kang, Jin Oh

    2011-09-01

    With the advance of modern radiation therapy technique, radiation dose conformation and dose distribution have improved dramatically. However, the progress does not completely fulfill the goal of cancer treatment such as improved local control or survival. The discordances with the clinical results are from the biophysical nature of photon, which is the main source of radiation therapy in current field, with the lower linear energy transfer to the target. As part of a natural progression, there recently has been a resurgence of interest in particle therapy, specifically using heavy charged particles, because these kinds of radiations serve theoretical advantages in both biological and physical aspects. The Korean government is to set up a heavy charged particle facility in Korea Institute of Radiological & Medical Sciences. This review introduces some of the elementary physics of the various particles for the sake of Korean radiation oncologists' interest.

  14. Basics of particle therapy I: physics

    PubMed Central

    Park, Seo Hyun

    2011-01-01

    With the advance of modern radiation therapy technique, radiation dose conformation and dose distribution have improved dramatically. However, the progress does not completely fulfill the goal of cancer treatment such as improved local control or survival. The discordances with the clinical results are from the biophysical nature of photon, which is the main source of radiation therapy in current field, with the lower linear energy transfer to the target. As part of a natural progression, there recently has been a resurgence of interest in particle therapy, specifically using heavy charged particles, because these kinds of radiations serve theoretical advantages in both biological and physical aspects. The Korean government is to set up a heavy charged particle facility in Korea Institute of Radiological & Medical Sciences. This review introduces some of the elementary physics of the various particles for the sake of Korean radiation oncologists' interest. PMID:22984664

  15. Quantum effects for particles channeling in a bent crystal

    NASA Astrophysics Data System (ADS)

    Feranchuk, Ilya; San, Nguyen Quang

    2016-09-01

    Quantum mechanical theory for channeling of the relativistic charged particles in the bent crystals is considered in the paper. Quantum effects of under-barrier tunneling are essential when the radius of the curvature is closed to its critical value. In this case the wave functions of the quasi-stationary states corresponding to the particles captured in a channel are presented in the analytical form. The efficiency of channeling of the particles and their angular distribution at the exit crystal surface are calculated. Characteristic experimental parameters for observation the quantum effects are estimated.

  16. The CMS Masterclass and Particle Physics Outreach

    SciTech Connect

    Cecire, Kenneth; Bardeen, Marjorie; McCauley, Thomas

    2014-01-01

    The CMS Masterclass enables high school students to analyse authentic CMS data. Students can draw conclusions on key ratios and particle masses by combining their analyses. In particular, they can use the ratio of W^+ to W^- candidates to probe the structure of the proton, they can find the mass of the Z boson, and they can identify additional particles including, tentatively, the Higgs boson. In the United States, masterclasses are part of QuarkNet, a long-term program that enables students and teachers to use cosmic ray and particle physics data for learning with an emphasis on data from CMS.

  17. Single-particle machine for quantum thermalization

    SciTech Connect

    Liao Jieqiao; Dong, H.; Sun, C. P.

    2010-05-15

    The long time accumulation of the random actions of a single particle 'reservoir' on its coupled system can transfer some temperature information of its initial state to the coupled system. This dynamic process can be referred to as a quantum thermalization in the sense that the coupled system can reach a stable thermal equilibrium with a temperature equal to that of the reservoir. We illustrate this idea based on the usual micromaser model, in which a series of initially prepared two-level atoms randomly pass through an electromagnetic cavity. It is found that, when the randomly injected atoms are initially prepared in a thermal equilibrium state with a given temperature, the cavity field will reach a thermal equilibrium state with the same temperature as that of the injected atoms. As in two limit cases, the cavity field can be cooled and 'coherently heated' as a maser process, respectively, when the injected atoms are initially prepared in ground and excited states. Especially, when the atoms in equilibrium are driven to possess some coherence, the cavity field may reach a higher temperature in comparison with the injected atoms. We also point out a possible experimental test for our theoretical prediction based on a superconducting circuit QED system.

  18. Nuclear physics in particle therapy: a review.

    PubMed

    Durante, Marco; Paganetti, Harald

    2016-09-01

    Charged particle therapy has been largely driven and influenced by nuclear physics. The increase in energy deposition density along the ion path in the body allows reducing the dose to normal tissues during radiotherapy compared to photons. Clinical results of particle therapy support the physical rationale for this treatment, but the method remains controversial because of the high cost and of the lack of comparative clinical trials proving the benefit compared to x-rays. Research in applied nuclear physics, including nuclear interactions, dosimetry, image guidance, range verification, novel accelerators and beam delivery technologies, can significantly improve the clinical outcome in particle therapy. Measurements of fragmentation cross-sections, including those for the production of positron-emitting fragments, and attenuation curves are needed for tuning Monte Carlo codes, whose use in clinical environments is rapidly increasing thanks to fast calculation methods. Existing cross sections and codes are indeed not very accurate in the energy and target regions of interest for particle therapy. These measurements are especially urgent for new ions to be used in therapy, such as helium. Furthermore, nuclear physics hardware developments are frequently finding applications in ion therapy due to similar requirements concerning sensors and real-time data processing. In this review we will briefly describe the physics bases, and concentrate on the open issues.

  19. Nuclear physics in particle therapy: a review

    NASA Astrophysics Data System (ADS)

    Durante, Marco; Paganetti, Harald

    2016-09-01

    Charged particle therapy has been largely driven and influenced by nuclear physics. The increase in energy deposition density along the ion path in the body allows reducing the dose to normal tissues during radiotherapy compared to photons. Clinical results of particle therapy support the physical rationale for this treatment, but the method remains controversial because of the high cost and of the lack of comparative clinical trials proving the benefit compared to x-rays. Research in applied nuclear physics, including nuclear interactions, dosimetry, image guidance, range verification, novel accelerators and beam delivery technologies, can significantly improve the clinical outcome in particle therapy. Measurements of fragmentation cross-sections, including those for the production of positron-emitting fragments, and attenuation curves are needed for tuning Monte Carlo codes, whose use in clinical environments is rapidly increasing thanks to fast calculation methods. Existing cross sections and codes are indeed not very accurate in the energy and target regions of interest for particle therapy. These measurements are especially urgent for new ions to be used in therapy, such as helium. Furthermore, nuclear physics hardware developments are frequently finding applications in ion therapy due to similar requirements concerning sensors and real-time data processing. In this review we will briefly describe the physics bases, and concentrate on the open issues.

  20. The Coming Revolutions in Particle Physics

    NASA Astrophysics Data System (ADS)

    Quigg, Chris

    2006-12-01

    Wonderful opportunities await particle physics over the next decade, with new instruments and experiments poised to explore the frontiers of high energy, infinitesimal distances, and exquisite rarity. I will review the insights of the decade just past and show how they lead us to the brink of a new period of rapid and profound discovery. We expect answers to questions that speak to our understanding of the everyday world: why are there atoms? why chemistry? why stable structures? and even what makes life possible? We are probing the meaning of identity for the fundamental particles: what makes an electron an electron, a neutrino a neutrino, and a top quark a top quark? Important clues, including the remarkable neutrality of atoms, lead us to investigate the unity of the two main classes of matter, the quarks and leptons. Gravity and particle physics, long separate disciplines, are enjoying a stimulating reunion, and we are learning how to investigate—with experiments—new conceptions of spacetime. We look forward to the Large Hadron Collider at CERN to explore the a new and critical energy scale of one trillion electron volts. If we are inventive enough, we may be able to follow the LHC's rich menu with the physics opportunities offered by a linear electron-positron collider, a (muon storage ring) neutrino factory, and experiments that use natural sources. I expect a remarkable flowering of experimental particle physics, and of theoretical physics that engages with experiment.

  1. Quantum Mechanics for Beginning Physics Students

    NASA Astrophysics Data System (ADS)

    Schneider, Mark B.

    2010-10-01

    The past two decades of attention to introductory physics education has emphasized enhanced development of conceptual understanding to accompany calculational ability. Given this, it is surprising that current texts continue to rely on the Bohr model to develop a flawed intuition, and introduce correct atomic physics on an ad hoc basis. For example, Halliday, Resnick, and Walker describe the origin of atomic quantum numbers as such: "The restrictions on the values of the quantum number for the hydrogen atom, as listed in Table 39-2, are not arbitrary but come out of the solution to Schrödinger's equation." They give no further justification, but do point out the values are in conflict with the predictions of the Bohr model.

  2. Particle Physics Outreach to Secondary Education

    SciTech Connect

    Bardeen, Marjorie G.; Johansson, K.Erik; Young, M.Jean

    2011-11-21

    This review summarizes exemplary secondary education and outreach programs of the particle physics community. We examine programs from the following areas: research experiences, high-energy physics data for students, informal learning for students, instructional resources, and professional development. We report findings about these programs' impact on students and teachers and provide suggestions for practices that create effective programs from those findings. We also include some methods for assessing programs.

  3. PREFACE: Particles and Fields: Classical and Quantum

    NASA Astrophysics Data System (ADS)

    Asorey, M.; Clemente-Gallardo, J.; Marmo, G.

    2007-07-01

    This volume contains some of the contributions to the Conference Particles and Fields: Classical and Quantum, which was held at Jaca (Spain) in September 2006 to honour George Sudarshan on his 75th birthday. Former and current students, associates and friends came to Jaca to share a few wonderful days with George and his family and to present some contributions of their present work as influenced by George's impressive achievements. This book summarizes those scientific contributions which are presented as a modest homage to the master, collaborator and friend. At the social ceremonies various speakers were able to recall instances of his life-long activity in India, the United States and Europe, adding colourful remarks on the friendly and intense atmosphere which surrounded those collaborations, some of which continued for several decades. This meeting would not have been possible without the financial support of several institutions. We are deeply indebted to Universidad de Zaragoza, Ministerio de Educación y Ciencia de España (CICYT), Departamento de Ciencia, Tecnología y Universidad del Gobierno de Aragón, Universitá di Napoli 'Federico II' and Istituto Nazionale di Fisica Nucleare. Finally, we would like to thank the participants, and particularly George's family, for their contribution to the wonderful atmosphere achieved during the Conference. We would like also to acknowledge the authors of the papers collected in the present volume, the members of the Scientific Committee for their guidance and support and the referees for their generous work. M Asorey, J Clemente-Gallardo and G Marmo The Local Organizing Committee George Sudarshan George Sudarshan

    International Advisory Committee

    A. Ashtekhar (Pennsylvania State University, USA)
    L. J. Boya (Universidad de Zaragoza, Spain)
    I. Cirac (Max Planck Institute, Garching

  4. Cold Atoms, Statistical Physics and Quantum Simulations

    DTIC Science & Technology

    2010-07-22

    to be the development of robust theoretical techniques for the simulations of ultra-cold Bose gases and other quantum phenomena, such theoretical...finite-temperature effects in atom-chip interferometry of Bose -Einstein condensates, R. G. Scott, et al., Physical Review A, 063624 (2009). A copy of...March 2009. Mr Hodder was supported through a University of Otago Scholarship. He initially developed a simple single-site Hubbard model, which can be

  5. Microfluidic generation of multifunctional quantum dot barcode particles.

    PubMed

    Zhao, Yuanjin; Shum, Ho Cheung; Chen, Haosheng; Adams, Laura L A; Gu, Zhongze; Weitz, David A

    2011-06-15

    We develop a new strategy to prepare quantum dot (QD) barcode particles by polymerizing double-emulsion droplets prepared in capillary microfluidic devices. The resultant barcode particles are composed of stable QD-tagged core particles surrounded by hydrogel shells. These particles exhibit uniform spectral characteristics and excellent coding capability, as confirmed by photoluminescence analyses. By using double-emulsion droplets with two inner droplets of distinct phases as templates, we have also fabricated anisotropic magnetic barcode particles with two separate cores or with a Janus core. These particles enable optical encoding and magnetic separation, thus making them excellent functional barcode particles in biomedical applications.

  6. Modeling quantum physics with machine learning

    NASA Astrophysics Data System (ADS)

    Lopez-Bezanilla, Alejandro; Arsenault, Louis-Francois; Millis, Andrew; Littlewood, Peter; von Lilienfeld, Anatole

    2014-03-01

    Machine Learning (ML) is a systematic way of inferring new results from sparse information. It directly allows for the resolution of computationally expensive sets of equations by making sense of accumulated knowledge and it is therefore an attractive method for providing computationally inexpensive 'solvers' for some of the important systems of condensed matter physics. In this talk a non-linear regression statistical model is introduced to demonstrate the utility of ML methods in solving quantum physics related problem, and is applied to the calculation of electronic transport in 1D channels. DOE contract number DE-AC02-06CH11357.

  7. Particles, Waves, and the Interpretation of Quantum Mechanics

    ERIC Educational Resources Information Center

    Christoudouleas, N. D.

    1975-01-01

    Presents an explanation, without mathematical equations, of the basic principles of quantum mechanics. Includes wave-particle duality, the probability character of the wavefunction, and the uncertainty relations. (MLH)

  8. Classical and quantum particle dynamics in univariate background fields

    NASA Astrophysics Data System (ADS)

    Heinzl, T.; Ilderton, A.; King, B.

    2016-09-01

    We investigate deviations from the plane wave model in the interaction of charged particles with strong electromagnetic fields. A general result is that integrability of the dynamics is lost when going from lightlike to timelike or spacelike field dependence. For a special scenario in the classical regime we show how the radiation spectrum in the spacelike (undulator) case becomes well-approximated by the plane wave model in the high-energy limit, despite the two systems being Lorentz inequivalent. In the quantum problem, there is no analogue of the WKB-exact Volkov solution. Nevertheless, WKB and uniform-WKB approaches give good approximations in all cases considered. Other approaches that reduce the underlying differential equations from second to first order are found to miss the correct physics for situations corresponding to barrier transmission and wide-angle scattering.

  9. Is Particle Physics Ready for the LHC

    ScienceCinema

    Lykken, Joseph

    2016-07-12

    The advent of the Large Hadron Collider in 2007 entails daunting challenges to particle physicists. The first set of challenges will arise from trying to separate new physics from old. The second set of challenges will come in trying to interpret the new discoveries. I will describe a few of the scariest examples.

  10. Theoretical Studies in Elementary Particle Physics

    SciTech Connect

    Collins, John C.; Roiban, Radu S

    2013-04-01

    This final report summarizes work at Penn State University from June 1, 1990 to April 30, 2012. The work was in theoretical elementary particle physics. Many new results in perturbative QCD, in string theory, and in related areas were obtained, with a substantial impact on the experimental program.

  11. Visions: The coming revolutions in particle physics

    SciTech Connect

    Chris Quigg

    2002-04-11

    Wonderful opportunities await particle physics over the next decade, with the coming of the Large Hadron Collider to explore the 1-TeV scale (extending efforts at LEP and the Tevatron to unravel the nature of electroweak symmetry breaking) and many initiatives to develop the understanding of the problem of identity and the dimensionality of spacetime.

  12. A Vision of Nuclear and Particle Physics

    SciTech Connect

    Montgomery, Hugh E.

    2016-08-01

    This paper will consist of a selected, personal view of some of the issues associated with the intersections of nuclear and particle physics. As well as touching on the recent developments we will attempt to look at how those aspects of the subject might evolve over the next few years.

  13. Size and temperature dependent plasmons of quantum particles

    NASA Astrophysics Data System (ADS)

    Xiao, Mufei; Rakov, Nikifor

    2015-08-01

    This work reports on the influences of temperature changes on plasmons of metallic particles that are so small that electric carriers in the conduction band are forced to be at discrete sub-bands due to quantum confinement. In the framework of the electron-in-a-box model and with an every-electron-count computational scheme, the spatial electric distribution inside the particle is calculated. In the calculations, the intra-subband fluctuations are taken into account. The numerical results have shown that the small-particle plasmon frequency shifts with the temperature. The findings suggest that it would be possible to control the plasmons of quantum particles externally.

  14. Medical physics aspects of particle therapy.

    PubMed

    Jäkel, Oliver

    2009-11-01

    Charged particle beams offer an improved dose conformation to the target volume when compared with photon radiotherapy, with better sparing of normal tissue structures close to the target. In addition, beams of heavier ions exhibit a strong increase of the linear energy transfer in the Bragg peak when compared with the entrance region. These physical and biological properties make ion beams more favourable for radiation therapy of cancer than photon beams. As a consequence, particle therapy with protons and heavy ions has gained increasing interest worldwide. This contribution summarises the physical and biological principles of charged particle therapy with ion beams and highlights some of the developments in the field of beam delivery, the principles of treatment planning and the determination of absorbed dose in ion beams. The clinical experience gathered so far with carbon ion therapy is briefly reviewed.

  15. Beyond the standard model of particle physics.

    PubMed

    Virdee, T S

    2016-08-28

    The Large Hadron Collider (LHC) at CERN and its experiments were conceived to tackle open questions in particle physics. The mechanism of the generation of mass of fundamental particles has been elucidated with the discovery of the Higgs boson. It is clear that the standard model is not the final theory. The open questions still awaiting clues or answers, from the LHC and other experiments, include: What is the composition of dark matter and of dark energy? Why is there more matter than anti-matter? Are there more space dimensions than the familiar three? What is the path to the unification of all the fundamental forces? This talk will discuss the status of, and prospects for, the search for new particles, symmetries and forces in order to address the open questions.This article is part of the themed issue 'Unifying physics and technology in light of Maxwell's equations'.

  16. Current Experiments in Particle Physics (September 1996)

    SciTech Connect

    Galic, H.; Lehar, F.; Klyukhin, V.I.; Ryabov, Yu.G.; Bilak, S.V.; Illarionova, N.S.; Khachaturov, B.A.; Strokovsky, E.A.; Hoffman, C.M.; Kettle, P.-R.; Olin, A.; Armstrong, F.E.

    1996-09-01

    This report contains summaries of current and recent experiments in Particle Physics. Included are experiments at BEPC (Beijing), BNL, CEBAF, CERN, CESR, DESY, FNAL, Frascati, ITEP (Moscow), JINR (Dubna), KEK, LAMPF, Novosibirsk, PNPI (St. Petersburg), PSI, Saclay, Serpukhov, SLAC, and TRIUMF, and also several proton decay and solar neutrino experiments. Excluded are experiments that finished taking data before 1991. Instructions are given for the World Wide Web (WWW) searching of the computer database (maintained under the SLAC-SPIRES system) that contains the summaries. This report contains full summaries of 180 approved current and recent experiments in elementary particle physics. The focus of the report is on selected experiments which directly contribute to our better understanding of elementary particles and their properties such as masses, widths or lifetimes, and branching fractions.

  17. Current experiments in elementary particle physics

    SciTech Connect

    Wohl, C.G.; Armstrong, F.E., Oyanagi, Y.; Dodder, D.C.; Ryabov, Yu.G.; Frosch, R.; Olin, A.; Lehar, F.; Moskalev, A.N.; Barkov, B.P.

    1987-03-01

    This report contains summaries of 720 recent and current experiments in elementary particle physics (experiments that finished taking data before 1980 are excluded). Included are experiments at Brookhaven, CERN, CESR, DESY, Fermilab, Moscow Institute of Theoretical and Experimental Physics, Tokyo Institute of Nuclear Studies, KEK, LAMPF, Leningrad Nuclear Physics Institute, Saclay, Serpukhov, SIN, SLAC, and TRIUMF, and also experiments on proton decay. Instructions are given for searching online the computer database (maintained under the SLAC/SPIRES system) that contains the summaries. Properties of the fixed-target beams at most of the laboratories are summarized.

  18. Physics of the Blues: Music, Fourier and Wave - Particle Duality

    SciTech Connect

    Gibson, J. Murray

    2003-10-15

    Art and science are intimately connected. There is probably no art that reveals this more than music. Music can be used as a tool to teach physics and engineering to non-scientists, illustrating such diverse concepts as Fourier analysis and quantum mechanics. This colloquium is aimed in reverse, to explain some interesting aspects of music to physicists. Topics include: What determines the frequency of notes on a musical scale? What is harmony and why would Fourier care? Where did the blues come from? (We' re talking the 'physics of the blues', and not 'the blues of physics' - that's another colloquium). Is there a musical particle? The presentation will be accompanied by live keyboard demonstrations. The presenter will attempt to draw tenuous connections between the subject of his talk and his day job as Director of the Advanced Photon Source at Argonne National Laboratory.

  19. Energetic particle physics issues for ITER

    SciTech Connect

    Cheng, C.Z.; Budny, R.; Fu, G.Y.

    1996-12-31

    This paper summarizes our present understanding of the following energetic/alpha particle physics issues for the 21 MA, 20 TF coil ITER Interim Design configuration and operational scenarios: (a) toroidal field ripple effects on alpha particle confinement, (b) energetic particle interaction with low frequency MHD modes, (c) energetic particle excitation of toroidal Alfven eigenmodes, and (d) energetic particle transport due to MHD modes. TF ripple effects on alpha loss in ITER under a number of different operating conditions are found to be small with a maximum loss of 1%. With careful plasma control in ITER reversed-shear operation, TF ripple induced alpha loss can be reduced to below the nominal ITER design limit of 5%. Fishbone modes are expected to be unstable for {beta}{sub {alpha}} > 1%, and sawtooth stabilization is lost if the ideal kink growth rate exceeds 10% of the deeply trapped alpha precessional drift frequency evaluated at the q = 1 surface. However, it is expected that the fishbone modes will lead only to a local flattening of the alpha profile due to small banana size. MHD modes observed during slow decrease of stored energy after fast partial electron temperature collapse in JT-60U reversed-shear experiments may be resonant type instabilities; they may have implications on the energetic particle confinement in ITER reversed-shear operation. From the results of various TAE stability code calculations, ITER equilibria appear to lie close to TAE linear stability thresholds. However, the prognosis depends strongly on q profile and profiles of alpha and other high energy particles species. If TAE modes are unstable in ITER, the stochastic diffusion is the main loss mechanism, which scales with ({delta}B{sub r}/B){sup 2}, because of the relatively small alpha particle banana orbit size. For isolated TAE modes the particle loss is very small, and TAE modes saturate via the resonant wave-particle trapping process at very small amplitude.

  20. Summation of power series in particle physics

    NASA Astrophysics Data System (ADS)

    Fischer, Jan

    1999-04-01

    The large-order behaviour of power series used in quantum theory (perturbation series and the operator-product expansion) is discussed and relevant summation methods are reviewed. It is emphasised that, in most physically interesting situations, the mere knowledge of the expansion coefficients is not sufficient for a unique determination of the function expanded, and the necessity of some additional, extra-perturbative, input is pointed out. Several possible nonperturbative inputs are suggested. Applications to various problems of quantum chromodynamics are considered. This lecture was presented on the special Memorial Day dedicated to Professor Ryszard R˛czka at this Workshop. The last section is devoted to my personal recollections of this remarkable personality.

    1. Physics of Quantum Structures in Photovoltaic Devices

      NASA Technical Reports Server (NTRS)

      Raffaelle, Ryne P.; Andersen, John D.

      2005-01-01

      There has been considerable activity recently regarding the possibilities of using various nanostructures and nanomaterials to improve photovoltaic conversion of solar energy. Recent theoretical results indicate that dramatic improvements in device efficiency may be attainable through the use of three-dimensional arrays of zero-dimensional conductors (i.e., quantum dots) in an ordinary p-i-n solar cell structure. Quantum dots and other nanostructured materials may also prove to have some benefits in terms of temperature coefficients and radiation degradation associated with space solar cells. Two-dimensional semiconductor superlattices have already demonstrated some advantages in this regard. It has also recently been demonstrated that semiconducting quantum dots can also be used to improve conversion efficiencies in polymeric thin film solar cells. Improvement in thin film cells utilizing conjugated polymers has also be achieved through the use of one-dimensional quantum structures such as carbon nanotubes. It is believed that carbon nanotubes may contribute to both the disassociation as well as the carrier transport in the conjugated polymers used in certain thin film photovoltaic cells. In this paper we will review the underlying physics governing some of the new photovoltaic nanostructures being pursued, as well as the the current methods being employed to produce III-V, II-VI, and even chalcopyrite-based nanomaterials and nanostructures for solar cells.

    2. Teaching Quantum Physics in Upper Secondary School in France:

      ERIC Educational Resources Information Center

      Lautesse, Philippe; Vila Valls, Adrien; Ferlin, Fabrice; Héraud, Jean-Loup; Chabot, Hugues

      2015-01-01

      One of the main problems in trying to understand quantum physics is the nature of the referent of quantum theory. This point is addressed in the official French curriculum in upper secondary school. Starting in 2012, after about 20 years of absence, quantum physics has returned to the national program. On the basis of the historical construction…

    3. Cyclic Polyynes as Examples of the Quantum Mechanical Particle on a Ring

      ERIC Educational Resources Information Center

      Anderson, Bruce D.

      2012-01-01

      Many quantum mechanical models are discussed as part of the undergraduate physical chemistry course to help students understand the connection between eigenvalue expressions and spectroscopy. Typical examples covered include the particle in a box, the harmonic oscillator, the rigid rotor, and the hydrogen atom. This article demonstrates that…

    4. Physical realization of the Glauber quantum oscillator.

      PubMed

      Gentilini, Silvia; Braidotti, Maria Chiara; Marcucci, Giulia; DelRe, Eugenio; Conti, Claudio

      2015-11-02

      More than thirty years ago Glauber suggested that the link between the reversible microscopic and the irreversible macroscopic world can be formulated in physical terms through an inverted harmonic oscillator describing quantum amplifiers. Further theoretical studies have shown that the paradigm for irreversibility is indeed the reversed harmonic oscillator. As outlined by Glauber, providing experimental evidence of these idealized physical systems could open the way to a variety of fundamental studies, for example to simulate irreversible quantum dynamics and explain the arrow of time. However, supporting experimental evidence of reversed quantized oscillators is lacking. We report the direct observation of exploding n = 0 and n = 2 discrete states and Γ0 and Γ2 quantized decay rates of a reversed harmonic oscillator generated by an optical photothermal nonlinearity. Our results give experimental validation to the main prediction of irreversible quantum mechanics, that is, the existence of states with quantized decay rates. Our results also provide a novel perspective to optical shock-waves, potentially useful for applications as lasers, optical amplifiers, white-light and X-ray generation.

    5. Physical realization of the Glauber quantum oscillator

      NASA Astrophysics Data System (ADS)

      Gentilini, Silvia; Braidotti, Maria Chiara; Marcucci, Giulia; Delre, Eugenio; Conti, Claudio

      2015-11-01

      More than thirty years ago Glauber suggested that the link between the reversible microscopic and the irreversible macroscopic world can be formulated in physical terms through an inverted harmonic oscillator describing quantum amplifiers. Further theoretical studies have shown that the paradigm for irreversibility is indeed the reversed harmonic oscillator. As outlined by Glauber, providing experimental evidence of these idealized physical systems could open the way to a variety of fundamental studies, for example to simulate irreversible quantum dynamics and explain the arrow of time. However, supporting experimental evidence of reversed quantized oscillators is lacking. We report the direct observation of exploding n = 0 and n = 2 discrete states and Γ0 and Γ2 quantized decay rates of a reversed harmonic oscillator generated by an optical photothermal nonlinearity. Our results give experimental validation to the main prediction of irreversible quantum mechanics, that is, the existence of states with quantized decay rates. Our results also provide a novel perspective to optical shock-waves, potentially useful for applications as lasers, optical amplifiers, white-light and X-ray generation.

    6. Physical realization of the Glauber quantum oscillator

      PubMed Central

      Gentilini, Silvia; Braidotti, Maria Chiara; Marcucci, Giulia; DelRe, Eugenio; Conti, Claudio

      2015-01-01

      More than thirty years ago Glauber suggested that the link between the reversible microscopic and the irreversible macroscopic world can be formulated in physical terms through an inverted harmonic oscillator describing quantum amplifiers. Further theoretical studies have shown that the paradigm for irreversibility is indeed the reversed harmonic oscillator. As outlined by Glauber, providing experimental evidence of these idealized physical systems could open the way to a variety of fundamental studies, for example to simulate irreversible quantum dynamics and explain the arrow of time. However, supporting experimental evidence of reversed quantized oscillators is lacking. We report the direct observation of exploding n = 0 and n = 2 discrete states and Γ0 and Γ2 quantized decay rates of a reversed harmonic oscillator generated by an optical photothermal nonlinearity. Our results give experimental validation to the main prediction of irreversible quantum mechanics, that is, the existence of states with quantized decay rates. Our results also provide a novel perspective to optical shock-waves, potentially useful for applications as lasers, optical amplifiers, white-light and X-ray generation. PMID:26522653

    7. Particle scattering in loop quantum gravity.

      PubMed

      Modesto, Leonardo; Rovelli, Carlo

      2005-11-04

      We devise a technique for defining and computing -point functions in the context of a background-independent gravitational quantum field theory. We construct a tentative implementation of this technique in a perturbatively finite model defined using spin foam techniques in the context of loop quantum gravity.

    8. Perspectives in quantum physics: Epistemological, ontological and pedagogical An investigation into student and expert perspectives on the physical interpretation of quantum mechanics, with implications for modern physics instruction

      NASA Astrophysics Data System (ADS)

      Baily, Charles Raymond

      A common learning goal for modern physics instructors is for students to recognize a difference between the experimental uncertainty of classical physics and the fundamental uncertainty of quantum mechanics. Our studies suggest this notoriously difficult task may be frustrated by the intuitively realist perspectives of introductory students, and a lack of ontological flexibility in their conceptions of light and matter. We have developed a framework for understanding and characterizing student perspectives on the physical interpretation of quantum mechanics, and demonstrate the differential impact on student thinking of the myriad ways instructors approach interpretive themes in their introductory courses. Like expert physicists, students interpret quantum phenomena differently, and these interpretations are significantly influenced by their overall stances on questions central to the so-called measurement problem: Is the wave function physically real, or simply a mathematical tool? Is the collapse of the wave function an ad hoc rule, or a physical transition not described by any equation? Does an electron, being a form of matter, exist as a localized particle at all times? These questions, which are of personal and academic interest to our students, are largely only superficially addressed in our introductory courses, often for fear of opening a Pandora's Box of student questions, none of which have easy answers. We show how a transformed modern physics curriculum (recently implemented at the University of Colorado) may positively impact student perspectives on indeterminacy and wave-particle duality, by making questions of classical and quantum reality a central theme of our course, but also by making the beliefs of our students, and not just those of scientists, an explicit topic of discussion.

    9. Wave theories of non-laminar charged particle beams: from quantum to thermal regime

      NASA Astrophysics Data System (ADS)

      Fedele, Renato; Tanjia, Fatema; Jovanović, Dusan; de Nicola, Sergio; Ronsivalle, Concetta; Ronsivalle

      2014-04-01

      The standard classical description of non-laminar charged particle beams in paraxial approximation is extended to the context of two wave theories. The first theory that we discuss (Fedele R. and Shukla, P. K. 1992 Phys. Rev. A 45, 4045. Tanjia, F. et al. 2011 Proceedings of the 38th EPS Conference on Plasma Physics, Vol. 35G. Strasbourg, France: European Physical Society) is based on the Thermal Wave Model (TWM) (Fedele, R. and Miele, G. 1991 Nuovo Cim. D 13, 1527.) that interprets the paraxial thermal spreading of beam particles as the analog of quantum diffraction. The other theory is based on a recently developed model (Fedele, R. et al. 2012a Phys. Plasmas 19, 102106; Fedele, R. et al. 2012b AIP Conf. Proc. 1421, 212), hereafter called Quantum Wave Model (QWM), that takes into account the individual quantum nature of single beam particle (uncertainty principle and spin) and provides collective description of beam transport in the presence of quantum paraxial diffraction. Both in quantum and quantum-like regimes, the beam transport is governed by a 2D non-local Schrödinger equation, with self-interaction coming from the nonlinear charge- and current-densities. An envelope equation of the Ermakov-Pinney type, which includes collective effects, is derived for both TWM and QWM regimes. In TWM, such description recovers the well-known Sacherer's equation (Sacherer, F. J. 1971 IEEE Trans. Nucl. Sci. NS-18, 1105). Conversely, in the quantum regime and in Hartree's mean field approximation, one recovers the evolution equation for a single-particle spot size, i.e. for a single quantum ray spot in the transverse plane (Compton regime). We demonstrate that such quantum evolution equation contains the same information as the evolution equation for the beam spot size that describes the beam as a whole. This is done heuristically by defining the lowest QWM state accessible by a system of non-overlapping fermions. The latter are associated with temperature values that are

    10. Authenticated multi-user quantum key distribution with single particles

      NASA Astrophysics Data System (ADS)

      Lin, Song; Wang, Hui; Guo, Gong-De; Ye, Guo-Hua; Du, Hong-Zhen; Liu, Xiao-Fen

      2016-03-01

      Quantum key distribution (QKD) has been growing rapidly in recent years and becomes one of the hottest issues in quantum information science. During the implementation of QKD on a network, identity authentication has been one main problem. In this paper, an efficient authenticated multi-user quantum key distribution (MQKD) protocol with single particles is proposed. In this protocol, any two users on a quantum network can perform mutual authentication and share a secure session key with the assistance of a semi-honest center. Meanwhile, the particles, which are used as quantum information carriers, are not required to be stored, therefore the proposed protocol is feasible with current technology. Finally, security analysis shows that this protocol is secure in theory.

    11. On the physical realizability of quantum stochastic walks

      NASA Astrophysics Data System (ADS)

      Taketani, Bruno; Govia, Luke; Schuhmacher, Peter; Wilhelm, Frank

      Quantum walks are a promising framework that can be used to both understand and implement quantum information processing tasks. The recently developed quantum stochastic walk combines the concepts of a quantum walk and a classical random walk through open system evolution of a quantum system, and have been shown to have applications in as far reaching fields as artificial intelligence. However, nature puts significant constraints on the kind of open system evolutions that can be realized in a physical experiment. In this work, we discuss the restrictions on the allowed open system evolution, and the physical assumptions underpinning them. We then introduce a way to circumvent some of these restrictions, and simulate a more general quantum stochastic walk on a quantum computer, using a technique we call quantum trajectories on a quantum computer. We finally describe a circuit QED approach to implement discrete time quantum stochastic walks.

    12. Quantum Dots: An Experiment for Physical or Materials Chemistry

      ERIC Educational Resources Information Center

      Winkler, L. D.; Arceo, J. F.; Hughes, W. C.; DeGraff, B. A.; Augustine, B. H.

      2005-01-01

      An experiment is conducted for obtaining quantum dots for physical or materials chemistry. This experiment serves to both reinforce the basic concept of quantum confinement and providing a useful bridge between the molecular and solid-state world.

    13. Modern Particle Physics Event Generation with WHIZARD

      NASA Astrophysics Data System (ADS)

      Reuter, J.; Bach, F.; Chokoufé, B.; Kilian, W.; Ohl, T.; Sekulla, M.; Weiss, C.

      2015-05-01

      We describe the multi-purpose Monte-Carlo event generator WHIZARD for the simulation of high-energy particle physics experiments. Besides the presentation of the general features of the program like SM physics, BSM physics, and QCD effects, special emphasis will be given to the support of the most accurate simulation of the collider environments at hadron colliders and especially at future linear lepton colliders. On the more technical side, the very recent code refactoring towards a completely object-oriented software package to improve maintainability, flexibility and code development will be discussed. Finally, we present ongoing work and future plans regarding higher-order corrections, more general model support including the setup to search for new physics in vector boson scattering at the LHC, as well as several lines of performance improvements.

    14. Advanced analysis methods in particle physics

      SciTech Connect

      Bhat, Pushpalatha C.; /Fermilab

      2010-10-01

      Each generation of high energy physics experiments is grander in scale than the previous - more powerful, more complex and more demanding in terms of data handling and analysis. The spectacular performance of the Tevatron and the beginning of operations of the Large Hadron Collider, have placed us at the threshold of a new era in particle physics. The discovery of the Higgs boson or another agent of electroweak symmetry breaking and evidence of new physics may be just around the corner. The greatest challenge in these pursuits is to extract the extremely rare signals, if any, from huge backgrounds arising from known physics processes. The use of advanced analysis techniques is crucial in achieving this goal. In this review, I discuss the concepts of optimal analysis, some important advanced analysis methods and a few examples. The judicious use of these advanced methods should enable new discoveries and produce results with better precision, robustness and clarity.

    15. Quantum limited particle sensing in optical tweezers

      SciTech Connect

      Tay, J.W.; Hsu, Magnus T. L.; Bowen, Warwick P.

      2009-12-15

      Particle sensing in optical tweezers systems provides information on the position, velocity, and force of the specimen particles. The conventional quadrant detection scheme is applied ubiquitously in optical tweezers experiments to quantify these parameters. In this paper, we show that quadrant detection is nonoptimal for particle sensing in optical tweezers and propose an alternative optimal particle sensing scheme based on spatial homodyne detection. A formalism for particle sensing in terms of transverse spatial modes is developed and numerical simulations of the efficacies of both quadrant and spatial homodyne detection are shown. We demonstrate that 1 order of magnitude improvement in particle sensing sensitivity can be achieved using spatial homodyne over quadrant detection.

    16. Recasting particle physics by entangling physics, history and philosophy

      NASA Astrophysics Data System (ADS)

      Bertozzi, Eugenio; Levrini, Olivia

      2016-05-01

      -1The paper presents the design process we followed to recast particle physics so as to make it conceptually relevant for secondary school students. In this design process, the concept of symmetry was assumed as core-idea because of its structural and foundational role in particle physics, its crosscutting character and its epistemological and philosophical value. The first draft of the materials was tested in a pilot-study which involved 19 students of a regular class (grade 13) of an Italian school. The data analysis showed that the students were in their "regime of competence" for grasping subtle nuances of the materials and for providing important hints for revising them. In particular, students' reactions brought into light the need of clarifying the "foundational" character that symmetry attained in twentieth-century physics. The delicate step of re-thinking the materials required the researchers to articulate the complex relationship between researches on physics teaching, history and philosophy of physics. This analytic phase resulted in a version of the materials which implies the students to be guided to grasp the meaning of symmetry as normative principle in twentieth-century physics, throughout the exploration of the different meanings assumed by symmetry over time. The whole process led also to the production of an essential, on-line version, of the materials targeted to a wider audience.

    17. Measurement theory in local quantum physics

      SciTech Connect

      Okamura, Kazuya Ozawa, Masanao

      2016-01-15

      In this paper, we aim to establish foundations of measurement theory in local quantum physics. For this purpose, we discuss a representation theory of completely positive (CP) instruments on arbitrary von Neumann algebras. We introduce a condition called the normal extension property (NEP) and establish a one-to-one correspondence between CP instruments with the NEP and statistical equivalence classes of measuring processes. We show that every CP instrument on an atomic von Neumann algebra has the NEP, extending the well-known result for type I factors. Moreover, we show that every CP instrument on an injective von Neumann algebra is approximated by CP instruments with the NEP. The concept of posterior states is also discussed to show that the NEP is equivalent to the existence of a strongly measurable family of posterior states for every normal state. Two examples of CP instruments without the NEP are obtained from this result. It is thus concluded that in local quantum physics not every CP instrument represents a measuring process, but in most of physically relevant cases every CP instrument can be realized by a measuring process within arbitrary error limits, as every approximately finite dimensional von Neumann algebra on a separable Hilbert space is injective. To conclude the paper, the concept of local measurement in algebraic quantum field theory is examined in our framework. In the setting of the Doplicher-Haag-Roberts and Doplicher-Roberts theory describing local excitations, we show that an instrument on a local algebra can be extended to a local instrument on the global algebra if and only if it is a CP instrument with the NEP, provided that the split property holds for the net of local algebras.

    18. Current experiments in elementary particle physics

      SciTech Connect

      Wohl, C.G.; Armstrong, F.E.; Trippe, T.G.; Yost, G.P. ); Oyanagi, Y. ); Dodder, D.C. ); Ryabov, Yu.G.; Slabospitsky, S.R. . Inst. Fiziki Vysokikh Ehnergij); Frosch, R. (Swiss Inst. for Nuclear Research, Villigen (Switzerla

      1989-09-01

      This report contains summaries of 736 current and recent experiments in elementary particle physics (experiments that finished taking data before 1982 are excluded). Included are experiments at Brookhaven, CERN, CESR, DESY, Fermilab, Tokyo Institute of Nuclear Studies, Moscow Institute of Theoretical and Experimental Physics, Joint Institute for Nuclear Research (Dubna), KEK, LAMPF, Novosibirsk, PSI/SIN, Saclay, Serpukhov, SLAC, and TRIUMF, and also several underground experiments. Also given are instructions for searching online the computer database (maintained under the SLAC/SPIRES system) that contains the summaries. Properties of the fixed-target beams at most of the laboratories are summarized.

    19. Current experiments in elementary particle physics. Revised

      SciTech Connect

      Galic, H.; Wohl, C.G.; Armstrong, B.; Dodder, D.C.; Klyukhin, V.I.; Ryabov, Yu.G.; Illarionova, N.S.; Lehar, F.; Oyanagi, Y.; Olin, A.; Frosch, R.

      1992-06-01

      This report contains summaries of 584 current and recent experiments in elementary particle physics. Experiments that finished taking data before 1986 are excluded. Included are experiments at Brookhaven, CERN, CESR, DESY, Fermilab, Tokyo Institute of Nuclear Studies, Moscow Institute of Theoretical and Experimental Physics, KEK, LAMPF, Novosibirsk, Paul Scherrer Institut (PSI), Saclay, Serpukhov, SLAC, SSCL, and TRIUMF, and also several underground and underwater experiments. Instructions are given for remote searching of the computer database (maintained under the SLAC/SPIRES system) that contains the summaries.

    20. Particle physics: recent successes and future prospects

      SciTech Connect

      Wojcicki, S.

      1984-12-01

      There is no doubt that as yet we do not have an ultimate theory of matter and forces in spite of the remarkable successes of the past decade. In this talk the author attempts to summarize briefly the historical background that led us to the present level of understanding, or more specifically to the standard model of particle physics. Subsequently the author describes several difficulties with this picture, continues with some possible indications of new physics, and finally ends with the discussion of the prospects for the future. 32 references.

    1. Quantum interface to charged particles in a vacuum

      NASA Astrophysics Data System (ADS)

      Okamoto, Hiroshi

      2015-11-01

      A superconducting qubit device suitable for interacting with a flying electron has recently been proposed [Okamoto and Nagatani, Appl. Phys. Lett. 104, 062604 (2014), 10.1063/1.4865244]. Either a clockwise or counterclockwise directed loop of half magnetic flux quantum encodes a qubit, which naturally interacts with any single charged particle with arbitrary kinetic energy. Here, the device's properties, sources of errors, and possible applications are studied in detail. In particular, applications include detection of a charged particle essentially without applying a classical force to it. Furthermore, quantum states can be transferred between an array of the proposed devices and the charged particle.

    2. Particle Physics from Almost-Commutative Spacetimes

      NASA Astrophysics Data System (ADS)

      van den Dungen, Koen; van Suijlekom, Walter D.

      2012-10-01

      Our aim in this review paper is to present the applications of Connes' noncommutative geometry to elementary particle physics. Whereas the existing literature is mostly focused on a mathematical audience, in this paper we introduce the ideas and concepts from noncommutative geometry using physicists' terminology, gearing towards the predictions that can be derived from the noncommutative description. Focusing on a light package of noncommutative geometry (so-called "almost-commutative manifolds"), we shall introduce in steps: electrodynamics, the electroweak model, culminating in the full Standard Model. We hope that our approach helps in understanding the role noncommutative geometry could play in describing particle physics models, eventually unifying them with Einstein's (geometrical) theory of gravity.

    3. Semiconductor detectors in nuclear and particle physics

      SciTech Connect

      Rehak, P.; Gatti, E.

      1992-12-31

      Semiconductor detectors for elementary particle physics and nuclear physics in the energy range above 1 GeV are briefly reviewed. In these two fields semiconductor detectors are used mainly for the precise position sensing. In a typical experiment, the position of a fast charged particle crossing a relatively thin semiconductor detector is measured. The position resolution achievable by semiconductor detectors is compared with the resolution achievable by gas filled position sensing detectors. Semiconductor detectors are divided into two groups: Classical semiconductor diode detectors and semiconductor memory detectors. Principles of the signal formation and the signal read-out for both groups of detectors are described. New developments of silicon detectors of both groups are reported.

    4. Group action in topos quantum physics

      NASA Astrophysics Data System (ADS)

      Flori, C.

      2013-03-01

      Topos theory has been suggested first by Isham and Butterfield, and then by Isham and Döring, as an alternative mathematical structure within which to formulate physical theories. In particular, it has been used to reformulate standard quantum mechanics in such a way that a novel type of logic is used to represent propositions. In this paper, we extend this formulation to include the notion of a group and group transformation in such a way that we overcome the problem of twisted presheaves. In order to implement this we need to change the type of topos involved, so as to render the notion of continuity of the group action meaningful.

    5. Group action in topos quantum physics

      SciTech Connect

      Flori, C.

      2013-03-15

      Topos theory has been suggested first by Isham and Butterfield, and then by Isham and Doering, as an alternative mathematical structure within which to formulate physical theories. In particular, it has been used to reformulate standard quantum mechanics in such a way that a novel type of logic is used to represent propositions. In this paper, we extend this formulation to include the notion of a group and group transformation in such a way that we overcome the problem of twisted presheaves. In order to implement this we need to change the type of topos involved, so as to render the notion of continuity of the group action meaningful.

    6. FINAL REPORT: GEOMETRY AND ELEMENTARY PARTICLE PHYSICS

      SciTech Connect

      Singer, Isadore M.

      2008-03-04

      The effect on mathematics of collaborations between high-energy theoretical physics and modern mathematics has been remarkable. Mirror symmetry has revolutionized enumerative geometry, and Seiberg-Witten invariants have greatly simplified the study of four manifolds. And because of their application to string theory, physicists now need to know cohomology theory, characteristic classes, index theory, K-theory, algebraic geometry, differential geometry, and non-commutative geometry. Much more is coming. We are experiencing a deeper contact between the two sciences, which will stimulate new mathematics essential to the physicists’ quest for the unification of quantum mechanics and relativity. Our grant, supported by the Department of Energy for twelve years, has been instrumental in promoting an effective interaction between geometry and string theory, by supporting the Mathematical Physics seminar, postdoc research, collaborations, graduate students and several research papers.

    7. Scale Hierarchies in Particle Physics and Cosmology

      NASA Astrophysics Data System (ADS)

      Antoniadis, I.

      2016-11-01

      We discuss possible connections between several scales in particle physics andcosmology, such the the electroweak, inflation, dark energy and Planck scales. We thendescribe the phenomenology of a model of supersymmetry breaking in the presence ofa tiny (tunable) positive cosmological constant. The model is coupled to the MSSM, leading to calculable soft supersymmetry breaking masses and a distinct low energy phenomenologythat allows to differentiate it from other models of supersymmetry breakingand mediation mechanisms.

    8. Current experiments in elementary-particle physics

      NASA Astrophysics Data System (ADS)

      Wohl, C. G.; Armstrong, F. E.; Rittenberg, A.

      1983-03-01

      Microfiche are included which contain summaries of 479 experiments in elementary particle physics. Experiments are included at the following laboratories: Brookhaven (ENL); CERN; DESY; Fermilab. (FNAL); Institute for Nuclear Studies (INS); KEK; LAMPF; Serpukhov (SERP); SIN; SLAC; and TRIUMP. Also, summries of proton decay experiments are included. A list of experiments and titles is included; and a beam-target-momentum index and a spokesperson index are given. Properties of beams at the facilities are tabulated.

    9. Current experiments in elementary particle physics. Revision

      SciTech Connect

      Galic, H.; Armstrong, F.E.; von Przewoski, B.

      1994-08-01

      This report contains summaries of 568 current and recent experiments in elementary particle physics. Experiments that finished taking data before 1988 are excluded. Included are experiments at BEPC (Beijing), BNL, CEBAF, CERN, CESR, DESY, FNAL, INS (Tokyo), ITEP (Moscow), IUCF (Bloomington), KEK, LAMPF, Novosibirsk, PNPI (St. Petersburg), PSI, Saclay, Serpukhov, SLAC, and TRIUMF, and also several underground and underwater experiments. Instructions are given for remote searching of the computer database (maintained under the SLAC/SPIRES system) that contains the summaries.

    10. The Qubit as Key to Quantum Physics Part II: Physical Realizations and Applications

      ERIC Educational Resources Information Center

      Dür, Wolfgang; Heusler, Stefan

      2016-01-01

      Using the simplest possible quantum system--the qubit--the fundamental concepts of quantum physics can be introduced. This highlights the common features of many different physical systems, and provides a unifying framework when teaching quantum physics at the high school or introductory level. In a previous "TPT" article and in a…

    11. Quantum-classical correspondence for a particle in a homogeneous field

      NASA Astrophysics Data System (ADS)

      Singh, Sumita; Suman, Smriti P.; Singh, Vijay A.

      2016-11-01

      The correspondence principle provides a prescription to connect quantum physics to classical. It asserts that the physical quantities evaluated quantum mechanically approach their respective classical values for large quantum numbers. This has been shown for the pedagogically important cases of the particle in a box and a harmonic oscillator. However, a particle in a constant field has a wave function related to the Airy function and has at best been treated numerically. Employing energy eigenstates we obtain the expectation values of the position, the momentum and their moments upto fourth order, rigorously and without resorting to numerical or graphical techniques. We compare them with the corresponding classical values. We also examine the uncertainty product for the system.

    12. Research program in particle physics. Progress report, January 1, 1993--December 1993

      SciTech Connect

      Sudarshan, E.C.G.; Dicus, D.A.; Ritchie, J.L.; Lang, K.

      1993-05-01

      This report is the progress report for DOE funded support of particle physics work at the University of Texas, Austin. Support was divided between theoretical and experimental programs, and each is reviewed separately in the report. Theoretical effort was divided between three general areas: quantum gravity and mathematical physics; phenomenology; and quantum mechanics and quantum field theory. Experimental effort was primarily directed toward AGS experiments at Brookhaven, to look for rare kaon decays. AGS experiments 791 and 871 are described, along with BNL experiment 888.

    13. Charting the Course for Elementary Particle Physics

      DOE R&D Accomplishments Database

      Richter, B.

      2007-02-16

      "It was the best of times; it was the worst of times" is the way Dickens begins the Tale of Two Cities. The line is appropriate to our time in particle physics. It is the best of times because we are in the midst of a revolution in understanding, the third to occur during my career. It is the worst of times because accelerator facilities are shutting down before new ones are opening, restricting the opportunity for experiments, and because of great uncertainty about future funding. My task today is to give you a view of the most important opportunities for our field under a scenario that is constrained by a tight budget. It is a time when we cannot afford the merely good, but must give first priority to the really important. The defining theme of particle physics is to learn what the universe is made of and how it all works. This definition spans the full range of size from the largest things to the smallest things. This particle physics revolution has its origins in experiments that look at both.

    14. Charting the Course for Elementary Particle Physics

      SciTech Connect

      Richter, Burton

      2007-02-20

      ''It was the best of times; it was the worst of times'' is the way Dickens begins the Tale of Two Cities. The line is appropriate to our time in particle physics. It is the best of times because we are in the midst of a revolution in understanding, the third to occur during my career. It is the worst of times because accelerator facilities are shutting down before new ones are opening, restricting the opportunity for experiments, and because of great uncertainty about future funding. My task today is to give you a view of the most important opportunities for our field under a scenario that is constrained by a tight budget. It is a time when we cannot afford the merely good, but must give first priority to the really important. The defining theme of particle physics is to learn what the universe is made of and how it all works. This definition spans the full range of size from the largest things to the smallest things. This particle physics revolution has its origins in experiments that look at both.

    15. Exactly solvable interacting two-particle quantum graphs

      NASA Astrophysics Data System (ADS)

      Bolte, Jens; Garforth, George

      2017-03-01

      We construct models of exactly solvable two-particle quantum graphs with certain non-local two-particle interactions, establishing appropriate boundary conditions via suitable self-adjoint realisations of the two-particle Laplacian. Showing compatibility with the Bethe ansatz method, we calculate quantisation conditions in the form of secular equations from which the spectra can be deduced. We compare spectral statistics of some examples to well known results in random matrix theory, analysing the chaotic properties of their classical counterparts.

    16. BOOK REVIEW: Quantum Physics in One Dimension

      NASA Astrophysics Data System (ADS)

      Logan, David

      2004-05-01

      To a casual ostrich the world of quantum physics in one dimension may sound a little one-dimensional, suitable perhaps for those with an unhealthy obsession for the esoteric. Nothing of course could be further from the truth. The field is remarkably rich and broad, and for more than fifty years has thrown up innumerable challenges. Theorists, realising that the role of interactions in 1D is special and that well known paradigms of higher dimensions (Fermi liquid theory for example) no longer apply, took up the challenge of developing new concepts and techniques to understand the undoubted pecularities of one-dimensional systems. And experimentalists have succeeded in turning pipe dreams into reality, producing an impressive and ever increasing array of experimental realizations of 1D systems, from the molecular to the mesoscopic---spin and ladder compounds, organic superconductors, carbon nanotubes, quantum wires, Josephson junction arrays and so on. Many books on the theory of one-dimensional systems are however written by experts for experts, and tend as such to leave the non-specialist a touch bewildered. This is understandable on both fronts, for the underlying theoretical techniques are unquestionably sophisticated and not usually part of standard courses in many-body theory. A brave author it is then who aims to produce a well rounded, if necessarily partial, overview of quantum physics in one dimension, accessible to a beginner yet taking them to the edge of current research, and providing en route a thorough grounding in the fundamental ideas, basic methods and essential phenomenology of the field. It is of course the brave who succeed in this world, and Thierry Giamarchi does just that with this excellent book, written by an expert for the uninitiated. Aimed in particular at graduate students in theoretical condensed matter physics, and assumimg little theoretical background on the part of the reader (well just a little), Giamarchi writes in a refreshingly

    17. Current experiments in particle physics - particle data group

      SciTech Connect

      Galic, H.; Lehar, F.; Kettle, P.R.

      1996-09-01

      This report contains summaries of current and recent experiments in Particle Physics. Included are experiments at BEPC (Beijing), BNL, CEBAF, CERN, CESR, DESY, FNAL, Frascati, ITEP (Moscow), JINR (Dubna), KEK, LAMPF, Novosibirsk, PNPI (St. Petersburg), PSI, Saclay, Serpukhov, SLAC, and TRIUMF, and also several proton decay and solar neutrino experiments. Excluded are experiments that finished taking data before 1991. Instructions are given for the World Wide Web (WWW) searching of the computer database (maintained under the SLAC-SPIRES system) that contains the summaries.

    18. Quantum statistical imaging of particles without restriction of the diffraction limit.

      PubMed

      Cui, Jin-Ming; Sun, Fang-Wen; Chen, Xiang-Dong; Gong, Zhao-Jun; Guo, Guang-Can

      2013-04-12

      A quantum measurement method based on the quantum nature of antibunching photon emission has been developed to detect single particles without the restriction of the diffraction limit. By simultaneously counting the single-photon and two-photon signals with fluorescence microscopy, the images of nearby nitrogen-vacancy centers in diamond at a distance of 8.5±2.4  nm have been successfully reconstructed. Also their axes information was optically obtained. This quantum statistical imaging technique, with a simple experimental setup, can also be easily generalized in the measuring and distinguishing of other physical properties with any overlapping, which shows high potential in future image and study of coupled quantum systems for quantum information techniques.

    19. Nuclear and particle physics in the early universe

      NASA Technical Reports Server (NTRS)

      Schramm, D. N.

      1981-01-01

      Basic principles and implications of Big Bang cosmology are reviewed, noting the physical evidence of a previous universe temperature of 10,000 K and theoretical arguments such as grand unification decoupling indicating a primal temperature of 10 to the 15th eV. The Planck time of 10 to the -43rd sec after the Big Bang is set as the limit before which gravity was quantized and nothing is known. Gauge theories of elementary particle physics are reviewed for successful predictions of similarity in weak and electromagnetic interactions and quantum chromodynamic predictions for strong interactions. The large number of photons in the universe relative to the baryons is considered and the grand unified theories are cited as showing the existence of baryon nonconservation as an explanation. Further attention is given to quark-hadron phase transition, the decoupling for the weak interaction and relic neutrinos, and Big Bang nucleosynthesis.

    20. Designing Learning Environments to Teach Interactive Quantum Physics

      ERIC Educational Resources Information Center

      Puente, Sonia M. Gomez; Swagten, Henk J. M.

      2012-01-01

      This study aims at describing and analysing systematically an interactive learning environment designed to teach Quantum Physics, a second-year physics course. The instructional design of Quantum Physics is a combination of interactive lectures (using audience response systems), tutorials and self-study in unit blocks, carried out with small…

    1. Refined Characterization of Student Perspectives on Quantum Physics

      ERIC Educational Resources Information Center

      Baily, Charles; Finkelstein, Noah D.

      2010-01-01

      The perspectives of introductory classical physics students can often negatively influence how those students later interpret quantum phenomena when taking an introductory course in modern physics. A detailed exploration of student perspectives on the interpretation of quantum physics is needed, both to characterize student understanding of…

    2. Quantum Humor: The Playful Side of Physics at Bohr's Institute for Theoretical Physics

      NASA Astrophysics Data System (ADS)

      Halpern, Paul

      2012-09-01

      From the 1930s to the 1950s, a period of pivotal developments in quantum, nuclear, and particle physics, physicists at Niels Bohr's Institute for Theoretical Physics in Copenhagen took time off from their research to write humorous articles, letters, and other works. Best known is the Blegdamsvej Faust, performed in April 1932 at the close of one of the Institute's annual conferences. I also focus on the Journal of Jocular Physics, a humorous tribute to Bohr published on the occasions of his 50th, 60th, and 70th birthdays in 1935, 1945, and 1955. Contributors included Léon Rosenfeld, Victor Weisskopf, George Gamow, Oskar Klein, and Hendrik Casimir. I examine their contributions along with letters and other writings to show that they offer a window into some issues in physics at the time, such as the interpretation of complementarity and the nature of the neutrino, as well as the politics of the period.

    3. Quantum Walks with Neutral Atoms: Quantum Interference Effects of One and Two Particles

      NASA Astrophysics Data System (ADS)

      Robens, Carsten; Brakhane, Stefan; Meschede, Dieter; Alberti, A.

      We report on the state of the art of quantum walk experiments with neutral atoms in state-dependent optical lattices. We demonstrate a novel state-dependent transport technique enabling the control of two spin-selective sublattices in a fully independent fashion. This transport technique allowed us to carry out a test of single-particle quantum interference based on the violation of the Leggett-Garg inequality and, more recently, to probe two-particle quantum interference effects with neutral atoms cooled into the motional ground state. These experiments lay the groundwork for the study of discrete-time quantum walks of strongly interacting, indistinguishable particles to demonstrate quantum cellular automata of neutral atoms.

    4. Teaching Quantum Interpretations: Revisiting the Goals and Practices of Introductory Quantum Physics Courses

      ERIC Educational Resources Information Center

      Baily, Charles; Finkelstein, Noah D.

      2015-01-01

      Most introductory quantum physics instructors would agree that transitioning students from classical to quantum thinking is an important learning goal, but may disagree on whether or how this can be accomplished. Although (and perhaps because) physicists have long debated the physical interpretation of quantum theory, many instructors choose to…

    5. The Coming Revolutions in Particle Physics

      ScienceCinema

      Quigg, Chris

      2016-07-12

      Wonderful opportunities await particle physics over the next decade, with new instruments and experiments poised to explore the frontiers of high energy, infinitesimal distances, and exquisite rarity. We look forward to the Large Hadron Collider at CERN to explore the 1-TeV scale (extending efforts at LEP and the Tevatron to unravel the nature of electroweak symmetry breaking) and many initiatives to develop our understanding of the problem of identity: what makes a neutrino a neutrino and a top quark a top quark. We suspect that the detection of proton decay is only a few orders of magnitude away in sensitivity. Astronomical observations should help to tell us what kinds of matter and energy make up the universe. We might even learn to read experiment for clues about the dimensionality of spacetime. If we are inventive enough, we may be able to follow this rich menu with the physics opportunities offered by a linear electron-positron collider and a (muon storage ring) neutrino factory. I expect a remarkable flowering of experimental particle physics, and of theoretical physics that engages with experiment.

    6. On the physical Hilbert space of loop quantum cosmology

      SciTech Connect

      Noui, Karim; Perez, Alejandro; Vandersloot, Kevin

      2005-02-15

      In this paper we present a model of Riemannian loop quantum cosmology with a self-adjoint quantum scalar constraint. The physical Hilbert space is constructed using refined algebraic quantization. When matter is included in the form of a cosmological constant, the model is exactly solvable and we show explicitly that the physical Hilbert space is separable, consisting of a single physical state. We extend the model to the Lorentzian sector and discuss important implications for standard loop quantum cosmology.

    7. Atomic physics: A milestone in quantum computing

      NASA Astrophysics Data System (ADS)

      Bartlett, Stephen D.

      2016-08-01

      Quantum computers require many quantum bits to perform complex calculations, but devices with more than a few bits are difficult to program. A device based on five atomic quantum bits shows a way forward. See Letter p.63

    8. Quantum particle probe of the Kerr naked singularity

      NASA Astrophysics Data System (ADS)

      Gurtug, O.; Halilsoy, M.

      2017-01-01

      We investigate Kerr's timelike naked singularity within the framework of quantum mechanics. A quantum particle in the form of a massive boson is sent in the plane θ = π/2 to the naked ring singularity of Kerr which develops for the overspinning case (a>M) to test it from a quantum picture. This singularity is analysed in two different coordinate systems. We show that the spatial operator of the Klein-Gordon equation both in Boyer-Lindquist and in the dragging coordinate systems has a unique self-adjoint extension. As a result, the classical Kerr's ring singularity becomes quantum regular, if it is probed with massive bosonic particles obeying the Klein-Gordon equation.

    9. Tests of the particle physics-physical cosmology interface

      SciTech Connect

      Schramm, D.N. |

      1993-01-01

      Three interrelated interfaces of particle physics and physical cosmology are discussed: (1) inflation and other phase transitions; (2) Big Bang Nucleosynthesis (and also the quark-hadron transition); and (3) structure formation (including dark matter). Recent observations that affect each of these topics are discussed. Topic number 1 is shown to be consistent with the COBE observations but not proven and it may be having problems with some age-expansion data. Topic number 2 has now been well-tested and is an established ``pillar`` of the Big Bang. Topic number 3 is the prime arena of current physical cosmological activity. Experiments to resolve the current exciting, but still ambiguous, situation following the COBE results are discussed.

    10. Tests of the particle physics-physical cosmology interface

      SciTech Connect

      Schramm, D.N. Fermi National Accelerator Lab., Batavia, IL )

      1993-01-01

      Three interrelated interfaces of particle physics and physical cosmology are discussed: (1) inflation and other phase transitions; (2) Big Bang Nucleosynthesis (and also the quark-hadron transition); and (3) structure formation (including dark matter). Recent observations that affect each of these topics are discussed. Topic number 1 is shown to be consistent with the COBE observations but not proven and it may be having problems with some age-expansion data. Topic number 2 has now been well-tested and is an established pillar'' of the Big Bang. Topic number 3 is the prime arena of current physical cosmological activity. Experiments to resolve the current exciting, but still ambiguous, situation following the COBE results are discussed.

    11. Summary of the particle physics and technology working group

      SciTech Connect

      Stephan Lammel et al.

      2002-12-10

      Progress in particle physics has been tightly related to technological advances during the past half century. Progress in technologies has been driven in many cases by the needs of particle physics. Often, these advances have benefited fields beyond particle physics: other scientific fields, medicine, industrial development, and even found commercial applications. The particle physics and technology working group of Snowmass 2001 reviewed leading-edge technologies recently developed or in the need of development for particle physics. The group has identified key areas where technological advances are vital for progress in the field, areas of opportunities where particle physics may play a principle role in fostering progress, and areas where advances in other fields may directly benefit particle physics. The group has also surveyed the technologies specifically developed or enhanced by research in particle physics that benefit other fields and/or society at large.

    12. The Gibbs paradox and the physical criteria for indistinguishability of identical particles

      NASA Astrophysics Data System (ADS)

      Unnikrishnan, C. S.

      2016-08-01

      Gibbs paradox in the context of statistical mechanics addresses the issue of additivity of entropy of mixing gases. The usual discussion attributes the paradoxical situation to classical distinguishability of identical particles and credits quantum theory for enabling indistinguishability of identical particles to solve the problem. We argue that indistinguishability of identical particles is already a feature in classical mechanics and this is clearly brought out when the problem is treated in the language of information and associated entropy. We pinpoint the physical criteria for indistinguishability that is crucial for the treatment of the Gibbs’ problem and the consistency of its solution with conventional thermodynamics. Quantum mechanics provides a quantitative criterion, not possible in the classical picture, for the degree of indistinguishability in terms of visibility of quantum interference, or overlap of the states as pointed out by von Neumann, thereby endowing the entropy expression with mathematical continuity and physical reasonableness.

    13. TOPICS IN THE PHYSICS OF PARTICLE ACCELERATORS

      SciTech Connect

      Sessler, A.M.

      1984-07-01

      High energy physics, perhaps more than any other branch of science, is driven by technology. It is not the development of theory, or consideration of what measurements to make, which are the driving elements in our science. Rather it is the development of new technology which is the pacing item. Thus it is the development of new techniques, new computers, and new materials which allows one to develop new detectors and new particle-handling devices. It is the latter, the accelerators, which are at the heart of the science. Without particle accelerators there would be, essentially, no high energy physics. In fact. the advances in high energy physics can be directly tied to the advances in particle accelerators. Looking terribly briefly, and restricting one's self to recent history, the Bevatron made possible the discovery of the anti-proton and many of the resonances, on the AGS was found the {mu}-neutrino, the J-particle and time reversal non-invariance, on Spear was found the {psi}-particle, and, within the last year the Z{sub 0} and W{sup {+-}} were seen on the CERN SPS p-{bar p} collider. Of course one could, and should, go on in much more detail with this survey, but I think there is no need. It is clear that as better acceleration techniques were developed more and more powerful machines were built which, as a result, allowed high energy physics to advance. What are these techniques? They are very sophisticated and ever-developing. The science is very extensive and many individuals devote their whole lives to accelerator physics. As high energy experimental physicists your professional lives will be dominated by the performance of 'the machine'; i.e. the accelerator. Primarily you will be frustrated by the fact that it doesn't perform better. Why not? In these lectures, six in all, you should receive some appreciation of accelerator physics. We cannot, nor do we attempt, to make you into accelerator physicists, but we do hope to give you some insight into the

    14. Quantum optical implementation of quantum information processing and classical simulation of many-body physics from quantum information perspective

      NASA Astrophysics Data System (ADS)

      Wang, Bin

      This thesis is composed of two parts. In the first part we summarize our study on implementation of quantum information processing (QIP) in optical cavity QED systems, while in the second part we present our numerical investigations on strongly interacting Fermi systems using a powerful numerical algorithm developed from the perspective of quantum information theory. We explore various possible applications of cavity QED in the strong coupling regime to quantum information processing tasks theoretically, including efficient preparation of Schrodinger-cat states for traveling photon pulses, robust implementation of conditional quantum gates on neutral atoms, as well as implementation of a hybrid controlled SWAP gate. We analyze the feasibility and performance of our schemes by solving corresponding physical models either numerically or analytically. We implement a novel numerical algorithm called Time Evolving Block Decimation (TEBD), which was proposed by Vidal from the perspective of quantum information science. With this algorithm, we numerically study the ground state properties of strongly interacting fermions in an anisotropic optical lattice across a wide Feshbach resonance. The interactions in this system can be described by a general Hubbard model with particle assisted tunneling. For systems with equal spin population, we find that the Luther-Emery phase, which has been known to exist only for attractive on-site interactions in the conventional Hubbard model, could also be found even in the case with repulsive on-site interactions in the general Hubbard model. Using the TEBD algorithm, we also study the effect of particle assisted tunneling in spin-polarized systems. Fermi systems with unequal spin population and attractive interaction could allow the existence of exotic superfluidity, such as the Fulde-Ferrell-Larkin-Ovchinnikov (FFLO) state. In the general Hubbard model, such exotic FFLO pairing of fermions could be suppressed by high particle assisted

    15. The Underlying Physics in Wetted Particle Collisions

      NASA Astrophysics Data System (ADS)

      Donahue, Carly; Hrenya, Christine; Davis, Robert

      2008-11-01

      Wetted granular particles are relevant in many industries including the pharmaceutical and chemical industries and has applications to granulation, filtration, coagulation, spray coating, drying and pneumatic transport. In our current focus, we investigate the dynamics of a three-body normal wetted particle collision. In order to conduct collisions we use an apparatus called a ``Stokes Cradle,'' similar to the Newton's Cradle (desktop toy) except that the target particles are covered with oil. Here, we are able to vary the oil thickness, oil viscosity, and material properties. With a three particle collision there are four possible outcomes: fully agglomerated (FA); Newton's Cradle (NC), the striker and the first target ball are agglomerated and the last target ball is separated; Reverse Newton's Cradle (RNC), the striker is separated and the two targets are agglomerated; and fully separated (FS). Varying the properties of the collisions, we have observed all four outcomes. We use elastohydrodynamics as a theoretical basis for modeling the system. We also have considered the glass transition of the oil as the pressure increases upon impact and the cavitation of the oil as the pressure drops below the vapor pressure upon rebound. A toy model has been developed where the collision is modeled as a series of two-body collisions. A qualitative agreement between the toy model and experiments gives insight into the underlying physics.

    16. The Particle Physics Data Grid. Final Report

      SciTech Connect

      Livny, Miron

      2002-08-16

      The main objective of the Particle Physics Data Grid (PPDG) project has been to implement and evaluate distributed (Grid-enabled) data access and management technology for current and future particle and nuclear physics experiments. The specific goals of PPDG have been to design, implement, and deploy a Grid-based software infrastructure capable of supporting the data generation, processing and analysis needs common to the physics experiments represented by the participants, and to adapt experiment-specific software to operate in the Grid environment and to exploit this infrastructure. To accomplish these goals, the PPDG focused on the implementation and deployment of several critical services: reliable and efficient file replication service, high-speed data transfer services, multisite file caching and staging service, and reliable and recoverable job management services. The focus of the activity was the job management services and the interplay between these services and distributed data access in a Grid environment. Software was developed to study the interaction between HENP applications and distributed data storage fabric. One key conclusion was the need for a reliable and recoverable tool for managing large collections of interdependent jobs. An attached document provides an overview of the current status of the Directed Acyclic Graph Manager (DAGMan) with its main features and capabilities.

    17. Strange Particles and Heavy Ion Physics

      SciTech Connect

      Bassalleck, Bernd; Fields, Douglas

      2016-04-28

      This very long-running grant has supported many experiments in nuclear and particle physics by a group from the University of New Mexico. The gamut of these experiments runs from many aspects of Strangeness Nuclear Physics, to rare Kaon decays, to searches for exotic Hadrons such as Pentaquark or H-Dibaryon, and finally to Spin Physics within the PHENIX collaboration at RHIC. These experiments were performed at a number of laboratories worldwide: first and foremost at Brookhaven National Lab (BNL), but also at CERN, KEK, and most recently at J-PARC. In this Final Technical Report we summarize progress and achievements for this award since our last Progress Report, i.e. for the period of fall 2013 until the award’s termination on November 30, 2015. The report consists of two parts, representing our two most recent experimental efforts, participation in the Nucleon Spin Physics program of the PHENIX experiment at RHIC, the Relativistic Heavy Ion Collider at BNL – Task 1, led by Douglas Fields; and participation in several Strangeness Nuclear Physics experiments at J-PARC, the Japan Proton Accelerator Research Center in Tokai-mura, Japan – Task 2, led by Bernd Bassalleck.

    18. Performances and robustness of quantum teleportation with identical particles

      PubMed Central

      Marzolino, Ugo; Buchleitner, Andreas

      2016-01-01

      When quantum teleportation is performed with truly identical massive particles, indistinguishability allows us to teleport addressable degrees of freedom which do not identify particles, but, for example, orthogonal modes. The key resource of the protocol is a state of entangled modes, but the conservation of the total number of particles does not allow for perfect deterministic teleportation unless the number of particles in the resource state goes to infinity. Here, we study the convergence of teleportation performances in the above limit and provide sufficient conditions for asymptotic perfect teleportation. We also apply these conditions to the case of resource states affected by noise. PMID:26997896

    19. Performances and robustness of quantum teleportation with identical particles.

      PubMed

      Marzolino, Ugo; Buchleitner, Andreas

      2016-01-01

      When quantum teleportation is performed with truly identical massive particles, indistinguishability allows us to teleport addressable degrees of freedom which do not identify particles, but, for example, orthogonal modes. The key resource of the protocol is a state of entangled modes, but the conservation of the total number of particles does not allow for perfect deterministic teleportation unless the number of particles in the resource state goes to infinity. Here, we study the convergence of teleportation performances in the above limit and provide sufficient conditions for asymptotic perfect teleportation. We also apply these conditions to the case of resource states affected by noise.

    20. Quantum Gravity Explanation of the Wave-Particle Duality

      NASA Astrophysics Data System (ADS)

      Winterberg, Friedwardt

      2016-03-01

      A quantum gravity explanation of the quantum-mechanical wave-particle duality is given by the watt-less emission of gravitational waves from a particle described by the Dirac equation. This explanation is possible through the existence of negative energy, and hence negative mass solutions of Einstein's gravitational field equations. They permit to understand the Dirac equation as the equation for a gravitationally bound positive-negative mass (pole-dipole particle) two-body configuration, with the mass of the Dirac particle equal to the positive mass of the gravitational field binding the positive with the negative mass particle, and with the positive and negative mass particles making a luminal ``Zitterbewegung'' (quivering motion), emitting a watt-less oscillating positive-negative space curvature wave. Is it shown that this thusly produced ``Zitterbewegung'' reproduces the quantum potential of the Madelung-transformed Schrödinger equation. The watt-less gravitational wave emitted by the quivering particles is conjectured to be the de Broglie pilot wave.

    1. Pre-Service Physics Teachers' Opinions about the Difficulties in Understanding Introductory Quantum Physics Topics

      ERIC Educational Resources Information Center

      Kizilcik, Hasan Sahin; Yavas, Pervin Ünlü

      2017-01-01

      The aim of this study is to identify the opinions of pre-service physics teachers about the difficulties in introductory quantum physics topics. In this study conducted with twenty-five pre-service physics teachers, the case study method was used. The participants were interviewed about introductory quantum physics topics. The interviews were…

    2. Particle Physics: A New Course for Schools and Colleges.

      ERIC Educational Resources Information Center

      Swinbank, Elizabeth

      1992-01-01

      Considers questions relating to the introduction of particle physics into post-GCSE (General Certificate of Secondary Education) courses. Describes a project that is producing teacher and student materials to support the teaching of particle physics at this level. Presents a proposed syllabus for a particle physics module. (KR)

    3. (Medium energy particle physics): Annual progress report

      SciTech Connect

      Nefkens, B.M.K.

      1985-10-01

      Investigations currently carried out by the UCLA Particle Physics Research Group can be arranged into four programs: Pion-Nucleon Scattering; Tests of Charge Symmetry and Isospin Invariance; Light Nuclei (Strong Form Factors of /sup 3/H, /sup 3/He, /sup 4/He; Detailed Balance in pd /r reversible/ /gamma//sup 3/H; Interaction Dynamics); and Search for the Rare Decay /Mu//sup +/ /yields/ e/sup +/ + /gamma/ (MEGA). The general considerations which led to the choice of physics problems investigated by our group are given in the next section. We also outline the scope of the research being done which includes over a dozen experiments. The main body of this report details the research carried out in the past year, the status of various experiments, and new projects.

    4. Particle physics in the very early universe

      NASA Technical Reports Server (NTRS)

      Schramm, D. N.

      1981-01-01

      Events in the very early big bang universe in which elementary particle physics effects may have been dominant are discussed, with attention to the generation of a net baryon number by way of grand unification theory, and emphasis on the possible role of massive neutrinos in increasing current understanding of various cosmological properties and of the constraints placed on neutrino properties by cosmology. It is noted that when grand unification theories are used to describe very early universe interactions, an initially baryon-symmetrical universe can evolve a net baryon excess of 10 to the -9th to 10 to the -11th per photon, given reasonable parameters. If neutrinos have mass, the bulk of the mass of the universe may be in the form of leptons, implying that the form of matter most familiar to physical science may not be the dominant form of matter in the universe.

    5. Physics through the 1990s: Elementary-particle physics

      NASA Technical Reports Server (NTRS)

      1986-01-01

      The volume begins with a non-mathematical discussion of the motivation behind, and basic ideas of, elementary-particle physics theory and experiment. The progress over the past two decades with the quark model and unification of the electromagnetic and weak interactions is reviewed. Existing theoretical problems in the field, such as the origin of mass and the unification of the fundamental forces, are detailed, along with experimental programs to test the new theories. Accelerators, instrumentation, and detectors are described for both current and future facilities. Interactions with other areas of both theoretical and applied physics are presented. The sociology of the field is examined regarding the education of graduate students, the organization necessary in large-scale experiments, and the decision-making process involved in high-cost experiments. Finally, conclusions and recommendations for maintaining US excellence in theory and experiment are given. Appendices list both current and planned accelerators, and present statistical data on the US elementary-particle physics program. A glossary is included.

    6. Quantum spectra of Raman photon pairs from a mesoscopic particle

      NASA Astrophysics Data System (ADS)

      Ooi, C. H. Raymond; Loh, W. M. Edmund; Kam, C. H.

      2015-06-01

      Quantum Langevin formalism with noise operators is used to provide quantum descriptions of photon pairs (the Stokes and anti-Stokes fields) emitted by a mesoscopic spherical particle composed of quantum particles in a double Raman configuration. The spectra of the fields obtained are sensitive to the dimension of the microsphere and can be controlled by pump and control laser fields. Spectral peaks due to quantum coherence are Stark shifted by the laser fields experiencing autofocusing inside the spherical particle, causing broadening of peaks as the size of the microsphere increases. The antinormal-order spectrum is found to be identical to the normal-order spectrum. The anti-Stokes spectrum is identical to the Stokes spectrum when the linear dispersion is neglected. Frequency-dependent dielectric functions of the Stokes and anti-Stokes spectra corresponding to the linear dispersions of the particle yield narrow morphology-dependent resonance gain peaks at certain frequencies of the Stokes and anti-Stokes spectra that depend not only on the particle size but also on the angle of observation.

    7. Quantum principles and free particles. [evaluation of partitions

      NASA Technical Reports Server (NTRS)

      1976-01-01

      The quantum principles that establish the energy levels and degeneracies needed to evaluate the partition functions are explored. The uncertainty principle is associated with the dual wave-particle nature of the model used to describe quantized gas particles. The Schroedinger wave equation is presented as a generalization of Maxwell's wave equation; the former applies to all particles while the Maxwell equation applies to the special case of photon particles. The size of the quantum cell in phase space and the representation of momentum as a space derivative operator follow from the uncertainty principle. A consequence of this is that steady-state problems that are space-time dependent for the classical model become only space dependent for the quantum model and are often easier to solve. The partition function is derived for quantized free particles and, at normal conditions, the result is the same as that given by the classical phase integral. The quantum corrections that occur at very low temperatures or high densities are derived. These corrections for the Einstein-Bose gas qualitatively describe the condensation effects that occur in liquid helium, but are unimportant for most practical purposes otherwise. However, the corrections for the Fermi-Dirac gas are important because they quantitatively describe the behavior of high-density conduction electron gases in metals and explain the zero point energy and low specific heat exhibited in this case.

    8. Quantum Monte Carlo methods for nuclear physics

      SciTech Connect

      Carlson, Joseph A.; Gandolfi, Stefano; Pederiva, Francesco; Pieper, Steven C.; Schiavilla, Rocco; Schmidt, K. E,; Wiringa, Robert B.

      2014-10-19

      Quantum Monte Carlo methods have proved very valuable to study the structure and reactions of light nuclei and nucleonic matter starting from realistic nuclear interactions and currents. These ab-initio calculations reproduce many low-lying states, moments and transitions in light nuclei, and simultaneously predict many properties of light nuclei and neutron matter over a rather wide range of energy and momenta. We review the nuclear interactions and currents, and describe the continuum Quantum Monte Carlo methods used in nuclear physics. These methods are similar to those used in condensed matter and electronic structure but naturally include spin-isospin, tensor, spin-orbit, and three-body interactions. We present a variety of results including the low-lying spectra of light nuclei, nuclear form factors, and transition matrix elements. We also describe low-energy scattering techniques, studies of the electroweak response of nuclei relevant in electron and neutrino scattering, and the properties of dense nucleonic matter as found in neutron stars. A coherent picture of nuclear structure and dynamics emerges based upon rather simple but realistic interactions and currents.

    9. Quantum Monte Carlo methods for nuclear physics

      DOE PAGES

      Carlson, Joseph A.; Gandolfi, Stefano; Pederiva, Francesco; ...

      2014-10-19

      Quantum Monte Carlo methods have proved very valuable to study the structure and reactions of light nuclei and nucleonic matter starting from realistic nuclear interactions and currents. These ab-initio calculations reproduce many low-lying states, moments and transitions in light nuclei, and simultaneously predict many properties of light nuclei and neutron matter over a rather wide range of energy and momenta. We review the nuclear interactions and currents, and describe the continuum Quantum Monte Carlo methods used in nuclear physics. These methods are similar to those used in condensed matter and electronic structure but naturally include spin-isospin, tensor, spin-orbit, and three-bodymore » interactions. We present a variety of results including the low-lying spectra of light nuclei, nuclear form factors, and transition matrix elements. We also describe low-energy scattering techniques, studies of the electroweak response of nuclei relevant in electron and neutrino scattering, and the properties of dense nucleonic matter as found in neutron stars. A coherent picture of nuclear structure and dynamics emerges based upon rather simple but realistic interactions and currents.« less

    10. Quantum Monte Carlo methods for nuclear physics

      DOE PAGES

      Carlson, J.; Gandolfi, S.; Pederiva, F.; ...

      2015-09-09

      Quantum Monte Carlo methods have proved valuable to study the structure and reactions of light nuclei and nucleonic matter starting from realistic nuclear interactions and currents. These ab-initio calculations reproduce many low-lying states, moments, and transitions in light nuclei, and simultaneously predict many properties of light nuclei and neutron matter over a rather wide range of energy and momenta. The nuclear interactions and currents are reviewed along with a description of the continuum quantum Monte Carlo methods used in nuclear physics. These methods are similar to those used in condensed matter and electronic structure but naturally include spin-isospin, tensor, spin-orbit,more » and three-body interactions. A variety of results are presented, including the low-lying spectra of light nuclei, nuclear form factors, and transition matrix elements. Low-energy scattering techniques, studies of the electroweak response of nuclei relevant in electron and neutrino scattering, and the properties of dense nucleonic matter as found in neutron stars are also described. Furthermore, a coherent picture of nuclear structure and dynamics emerges based upon rather simple but realistic interactions and currents.« less

    11. Quantum Monte Carlo methods for nuclear physics

      SciTech Connect

      Carlson, J.; Gandolfi, S.; Pederiva, F.; Pieper, Steven C.; Schiavilla, R.; Schmidt, K. E.; Wiringa, R. B.

      2015-09-09

      Quantum Monte Carlo methods have proved valuable to study the structure and reactions of light nuclei and nucleonic matter starting from realistic nuclear interactions and currents. These ab-initio calculations reproduce many low-lying states, moments, and transitions in light nuclei, and simultaneously predict many properties of light nuclei and neutron matter over a rather wide range of energy and momenta. The nuclear interactions and currents are reviewed along with a description of the continuum quantum Monte Carlo methods used in nuclear physics. These methods are similar to those used in condensed matter and electronic structure but naturally include spin-isospin, tensor, spin-orbit, and three-body interactions. A variety of results are presented, including the low-lying spectra of light nuclei, nuclear form factors, and transition matrix elements. Low-energy scattering techniques, studies of the electroweak response of nuclei relevant in electron and neutrino scattering, and the properties of dense nucleonic matter as found in neutron stars are also described. Furthermore, a coherent picture of nuclear structure and dynamics emerges based upon rather simple but realistic interactions and currents.

    12. Quantum Monte Carlo methods for nuclear physics

      NASA Astrophysics Data System (ADS)

      Carlson, J.; Gandolfi, S.; Pederiva, F.; Pieper, Steven C.; Schiavilla, R.; Schmidt, K. E.; Wiringa, R. B.

      2015-07-01

      Quantum Monte Carlo methods have proved valuable to study the structure and reactions of light nuclei and nucleonic matter starting from realistic nuclear interactions and currents. These ab initio calculations reproduce many low-lying states, moments, and transitions in light nuclei, and simultaneously predict many properties of light nuclei and neutron matter over a rather wide range of energy and momenta. The nuclear interactions and currents are reviewed along with a description of the continuum quantum Monte Carlo methods used in nuclear physics. These methods are similar to those used in condensed matter and electronic structure but naturally include spin-isospin, tensor, spin-orbit, and three-body interactions. A variety of results are presented, including the low-lying spectra of light nuclei, nuclear form factors, and transition matrix elements. Low-energy scattering techniques, studies of the electroweak response of nuclei relevant in electron and neutrino scattering, and the properties of dense nucleonic matter as found in neutron stars are also described. A coherent picture of nuclear structure and dynamics emerges based upon rather simple but realistic interactions and currents.

    13. Exploring flocking via quantum many-body physics techniques

      NASA Astrophysics Data System (ADS)

      Souslov, Anton; Loewe, Benjamin; Goldbart, Paul M.

      2015-03-01

      Flocking refers to the spontaneous breaking of spatial isotropy and time-reversal symmetries in collections of bodies such as birds, fish, locusts, bacteria, and artificial active systems. The transport of matter along biopolymers using molecular motors also involves the breaking of these symmetries, which in some cases are known to be broken explicitly. We study these classical nonequilibrium symmetry-breaking phenomena by means of models of many strongly interacting particles that hop on a periodic lattice. We employ a mapping between the classical and quantum dynamics of many-body systems, combined with tools from many-body theory. In particular, we examine the formation and properties of nematic and polar order in low-dimensional, strongly-interacting active systems using techniques familiar from fermionic systems, such as self-consistent field theory and bosonization. Thus, we find that classical active systems can exhibit analogs of quantum phenomena such as spin-orbit coupling, magnetism, and superconductivity. The models we study connect the physics of asymmetric exclusion processes to the spontaneous emergence of transport and flow, and also provide a soluble cousin of Vicsek's model system of self-propelled particles.

    14. An extended relativistic quantum oscillator for ? particles

      NASA Astrophysics Data System (ADS)

      Nedjadi, Y.; Ait-Tahar, S.; Barrett, R. C.

      1998-04-01

      We introduce the extended Duffin-Kemmer-Petiau (DKP) oscillator obtained by combining two relativistic quantum oscillator models. In a study analogous to Kukulin, Loyola and Moshinsky's work on extended Dirac oscillators, we investigate whether this extended version has oscillator shells controllably independent from the spin-orbit coupling. This extended DKP oscillator is found to be exactly solvable for natural parity states. We calculate and discuss both the natural- and unnatural-parity eigenspectra of its spin-1 representation.

    15. Experimental particle physics. [Dept. of Physics, Drexel Univ

      SciTech Connect

      Steinberg, R.I.; Lane, C.E.

      1992-09-01

      The goals of this research are the experimental testing of fundamental theories of physics beyond the standard model and the exploration of cosmic phenomena through the techniques of particle physics. We are working on the MACRO experiment, which employs a large-area underground detector to search fore grand unification magnetic monopoles and dark matter candidates and to study cosmic ray muons as well as low- and high-energy neutrinos; the Chooz experiment to search for reactor neutrino oscillations at a distance of 1 km from the source; a new proposal (the Perry experiment) to construct a one-kiloton liquid scintillator in the Fairport, Ohio underground facility IMB to study neutrino oscillations with a 13 km baseline; and development of technology for improved liquid scintillators and for very-low-background materials in support of the MACRO and Perry experiments and for new solar neutrino experiments.

    16. Single particle sources and quantum heat fluctuations

      NASA Astrophysics Data System (ADS)

      Battista, F.

      2014-10-01

      The miniaturisation of electronic devices has been a well-known trend in engineering over almost 50 years. The technological advancement in the field can now provide an astonishing control of charge transport in mesoscopic structures. Single particle pumping, namely the control in time and space of the flow of an arbitrarily small number of electrons or holes, has been realised in various kind of structure with, in some cases, very high accuracies. The first half of the manuscript provides a brief overview of different experimental realisations of single particle sources. Though these devices allow to minimise charge fluctuations in the charge current, because of Heisenberg's uncertainty principle, the emitted particles are characterised by energy fluctuations. The consequences of it are of great relevance and presented in the second part of the paper.

    17. Single particle density of trapped interacting quantum gases

      SciTech Connect

      Bala, Renu; Bosse, J.; Pathak, K. N.

      2015-05-15

      An expression for single particle density for trapped interacting gases has been obtained in first order of interaction using Green’s function method. Results are easily simplified for homogeneous quantum gases and are found to agree with famous results obtained by Huang-Yang-Luttinger and Lee-Yang.

    18. Hermann Weyl's Phenomenological Contribution to Quantum Physics

      NASA Astrophysics Data System (ADS)

      Mastrobisi, Giorgio J.

      On examining carefully Weyl's writings one realizes that the great mathematician from Göttingen in his researches follows the programmatic scheme of the binomial of "wissenschaftliche Erkenntnis" (scientific Knowledge) and "philosophische Besinnung" (philosophical Reflection). In 1954 in a retrospective writing he affirmed: «The formulation of Einstein's Theory of Relativity and the Laws of Gravitation, valid in this context and corroborated by experimental proofs turning to experience, constitute a method which combines "Wesenanalyse" with "mathematische Konstruktion" of convincing and excellent exemplarity». This conviction has conducted him to a close collaboration with A. Einstein (documented by punctual correspondence) for the decisive formulation of the "General Theory of Relativity", but also of the Theory of unified Field of Gravitation and Electromagnetism and therefore the following formulation of some fundamental principles of Quantum Physics. So Weyl's theoretical formation was marked by the devotion toward a mathematical formalization ("mathematische Konstruktion") of physical phenomena, reporting each of them to the causal structure of the "mathematical thinking" and geometry, contemporarely to a strong inclination toward the phenomenological "Analysis of essence". He brings really a notable quantity of considerations in that 1954 essay by the point of view of the decisive role that the "pure Phenomenology" of Edmund Husserl developed in the determination of his scientific activity.

    19. Quantum heat fluctuations of single-particle sources.

      PubMed

      Battista, F; Moskalets, M; Albert, M; Samuelsson, P

      2013-03-22

      Optimal single electron sources emit regular streams of particles, displaying no low-frequency charge current noise. Because of the wave packet nature of the emitted particles, the energy is, however, fluctuating, giving rise to heat current noise. We investigate theoretically this quantum source of heat noise for an emitter coupled to an electronic probe in the hot-electron regime. The distribution of temperature and potential fluctuations induced in the probe is shown to provide direct information on the single-particle wave function properties and display strong nonclassical features.

    20. Probing Planckian physics in de Sitter space with quantum correlations

      SciTech Connect

      Feng, Jun; Zhang, Yao-Zhong; Gould, Mark D.; Fan, Heng; Sun, Cheng-Yi; Yang, Wen-Li

      2014-12-15

      We study the quantum correlation and quantum communication channel of both free scalar and fermionic fields in de Sitter space, while the Planckian modification presented by the choice of a particular α-vacuum has been considered. We show the occurrence of degradation of quantum entanglement between field modes for an inertial observer in curved space, due to the radiation associated with its cosmological horizon. Comparing with standard Bunch–Davies choice, the possible Planckian physics causes some extra decrement on the quantum correlation, which may provide the means to detect quantum gravitational effects via quantum information methodology in future. Beyond single-mode approximation, we construct proper Unruh modes admitting general α-vacua, and find a convergent feature of both bosonic and fermionic entanglements. In particular, we show that the convergent points of fermionic entanglement negativity are dependent on the choice of α. Moreover, an one-to-one correspondence between convergent points H{sub c} of negativity and zeros of quantum capacity of quantum channels in de Sitter space has been proved. - Highlights: • Quantum correlation and quantum channel in de Sitter space are studied. • Gibbons–Hawking effect causes entanglement degradation for static observer. • Planckian physics causes extra decrement on quantum correlation. • Convergent feature of negativity relies on the choice of alpha-vacua. • Link between negativity convergence and quantum channel capacity is given.

    1. Attention, Intention, and Will in Quantum Physics

      SciTech Connect

      Stapp, H.P.

      1999-05-01

      How is mind related to matter? This ancient question inphilosophy is rapidly becoming a core problem in science, perhaps themost important of all because it probes the essential nature of manhimself. The origin of the problem is a conflict between the mechanicalconception of human beings that arises from the precepts of classicalphysical theory and the very different idea that arises from ourintuition: the former reduces each of us to an automaton, while thelatter allows our thoughts to guide our actions. The dominantcontemporary approaches to the problem attempt to resolve this conflictby clinging to the classical concepts, and trying to explain away ourmisleading intuition. But a detailed argument given here shows why, in ascientific approach to this problem, it is necessary to use the morebasic principles of quantum physics, which bring the observer into thedynamics, rather than to accept classical precepts that are profoundlyincorrect precisely at the crucial point of the role of humanconsciousness in the dynamics of human brains. Adherence to the quantumprinciples yields a dynamical theory of the mind/brain/body system thatis in close accord with our intuitive idea of what we are. In particular,the need for a self-observing quantum system to pose certain questionscreates a causal opening that allowsmind/brain dynamics to have threedistinguishable but interlocked causal processes, one micro-local, onestochastic, and the third experiential. Passing to the classical limit inwhich the critical difference between zero and the finite actual value ofPlanck's constant is ignored not only eliminates the chemical processesthat are absolutely crucial to the functioning of actual brains, itsimultaneously blinds the resulting theoretical construct to the physicalfine structure wherein the effect of mind on matter lies: the use of thislimit in this context is totally unjustified from a physicsperspective.

    2. Quantum physics explains Newton's laws of motion

      NASA Astrophysics Data System (ADS)

      Ogborn, Jon; Taylor, Edwin F.

      2005-01-01

      Newton was obliged to give his laws of motion as fundamental axioms. But today we know that the quantum world is fundamental, and Newton’s laws can be seen as consequences of fundamental quantum laws. This article traces this transition from fundamental quantum mechanics to derived classical mechanics.

    3. A cellular automaton for the signed particle formulation of quantum mechanics

      NASA Astrophysics Data System (ADS)

      Sellier, J. M.; Kapanova, K. G.; Dimov, I.

      2017-02-01

      Recently, a new formulation of quantum mechanics, based on the concept of signed particles, has been suggested. In this paper, we introduce a cellular automaton which mimics the dynamics of quantum objects in the phase-space in a time-dependent fashion. This is twofold: it provides a simplified and accessible language to non-physicists who wants to simulate quantum mechanical systems, at the same time it enables a different way to explore the laws of Physics. Moreover, it opens the way towards hybrid simulations of quantum systems by combining full quantum models with cellular automata when the former fail. In order to show the validity of the suggested cellular automaton and its combination with the signed particle formalism, several numerical experiments are performed, showing very promising results. Being this article a preliminary study on quantum simulations in phase-space by means of cellular automata, some conclusions are drawn about the encouraging results obtained so far and the possible future developments.

    4. Quantum Field Theory in Condensed Matter Physics

      NASA Astrophysics Data System (ADS)

      Tsvelik, Alexei M.

      2007-01-01

      Preface; Acknowledgements; Part I. Introduction to Methods: 1. QFT: language and goals; 2. Connection between quantum and classical: path integrals; 3. Definitions of correlation functions: Wick's theorem; 4. Free bosonic field in an external field; 5. Perturbation theory: Feynman diagrams; 6. Calculation methods for diagram series: divergences and their elimination; 7. Renormalization group procedures; 8. O(N)-symmetric vector model below the transition point; 9. Nonlinear sigma models in two dimensions: renormalization group and 1/N-expansion; 10. O(3) nonlinear sigma model in the strong coupling limit; Part II. Fermions: 11. Path integral and Wick's theorem for fermions; 12. Interaction electrons: the Fermi liquid; 13. Electrodynamics in metals; 14. Relativistic fermions: aspects of quantum electrodynamics; 15. Aharonov-Bohm effect and transmutation of statistics; Part III. Strongly Fluctuating Spin Systems: Introduction; 16. Schwinger-Wigner quantization procedure: nonlinear sigma models; 17. O(3) nonlinear sigma model in (2+1) dimensions: the phase diagram; 18. Order from disorder; 19. Jordan-Wigner transformations for spin S=1/2 models in D=1, 2, 3; 20. Majorana representation for spin S=1/2 magnets: relationship to Z2 lattice gauge theories; 21. Path integral representations for a doped antiferromagnet; Part IV. Physics in the World of One Spatial Dimension: Introduction; 22. Model of the free bosonic massless scalar field; 23. Relevant and irrelevant fields; 24. Kosterlitz-Thouless transition; 25. Conformal symmetry; 26. Virasoro algebra; 27. Differential equations for the correlation functions; 28. Ising model; 29. One-dimensional spinless fermions: Tomonaga-Luttinger liquid; 30. One-dimensional fermions with spin: spin-charge separation; 31. Kac-Moody algebras: Wess-Zumino-Novikov-Witten model; 32. Wess-Zumino-Novikov-Witten model in the Lagrangian form: non-Abelian bosonization; 33. Semiclassical approach to Wess-Zumino-Novikov-Witten models; 34

    5. Physical optimization of quantum error correction circuits with spatially separated quantum dot spins.

      PubMed

      Wang, Hong-Fu; Zhu, Ai-Dong; Zhang, Shou

      2013-05-20

      We propose an efficient protocol for optimizing the physical implementation of three-qubit quantum error correction with spatially separated quantum dot spins via virtual-photon-induced process. In the protocol, each quantum dot is trapped in an individual cavity and each two cavities are connected by an optical fiber. We propose the optimal quantum circuits and describe the physical implementation for correcting both the bit flip and phase flip errors by applying a series of one-bit unitary rotation gates and two-bit quantum iSWAP gates that are produced by the long-range interaction between two distributed quantum dot spins mediated by the vacuum fields of the fiber and cavity. The protocol opens promising perspectives for long distance quantum communication and distributed quantum computation networks.

    6. Matter and Interactions: A Particle Physics Perspective

      ERIC Educational Resources Information Center

      Organtini, Giovanni

      2011-01-01

      In classical mechanics, matter and fields are completely separated; matter interacts with fields. For particle physicists this is not the case; both matter and fields are represented by particles. Fundamental interactions are mediated by particles exchanged between matter particles. In this article we explain why particle physicists believe in…

    7. A problem in particle physics and its Bayesian analysis

      NASA Astrophysics Data System (ADS)

      Landon, Joshua

      An up and coming field in contemporary nuclear and particle physics is "Lattice Quantum Chromodynamics", henceforth Lattice QCD. Indeed the 2004 Nobel Prize in Physics went to the developers of equations that describe QCD. In this dissertation, following a layperson's introduction to the structure of matter, we outline the statistical aspects of a problem in Lattice QCD faced by particle physicists, and point out the difficulties encountered by them in trying to address the problem. The difficulties stem from the fact that one is required to estimate a large -- conceptually infinite -- number of parameters based on a finite number of non-linear equations, each of which is a sum of exponential functions. We then present a plausible approach for solving the problem. Our approach is Bayesian and is driven by a computationally intensive Markov Chain Monte Carlo based solution. However, in order to invoke our approach we first look at the underlying anatomy of the problem and synthesize its essentials. These essentials reveal a pattern that can be harnessed via some assumptions, and this in turn enables us to outline a pathway towards a solution. We demonstrate the viability of our approach via simulated data, followed by its validation against real data provided to us by our physicist colleagues. Our approach yields results that in the past were not obtainable via alternate approaches. The contribution of this dissertation is two-fold. The first is a use of computationally intensive statistical technology to produce results in physics that could not be obtained using physics based techniques. Since the statistical architecture of the problem considered here can arise in other contexts as well, the second contribution of this dissertation is to indicate a plausible approach for addressing a generic class of problems wherein the number of parameters to be estimated exceeds the number of constraints, each constraint being a non-linear equation that is the sum of

    8. Recovering the quantum formalism from physically realist axioms.

      PubMed

      Auffèves, Alexia; Grangier, Philippe

      2017-03-03

      We present a heuristic derivation of Born's rule and unitary transforms in Quantum Mechanics, from a simple set of axioms built upon a physical phenomenology of quantization. This approach naturally leads to the usual quantum formalism, within a new realistic conceptual framework that is discussed in details. Physically, the structure of Quantum Mechanics appears as a result of the interplay between the quantized number of "modalities" accessible to a quantum system, and the continuum of "contexts" that are required to define these modalities. Mathematically, the Hilbert space structure appears as a consequence of a specific "extra-contextuality" of modalities, closely related to the hypothesis of Gleason's theorem, and consistent with its conclusions.

    9. Particle physics---Experimental. Annual progress report

      SciTech Connect

      Lord, J.J.; Boynton, P.E.; Burnett, T.H.; Wilkes, R.J.

      1991-08-21

      We are continuing a research program in particle astrophysics and high energy experimental particle physics. We have joined the DUMAND Collaboration, which is constructing a deep undersea astrophysical neutrino detector near Hawaii. Studies of high energy hadronic interactions using emulsion chamber techniques were also continued, using balloon flight exposures to ultra-high cosmic ray nuclei (JACEE) and accelerator beams. As members of the DUMAND Collaboration, we have responsibility for development a construction of critical components for the deep undersea neutrino detector facility. We have designed and developed the acoustical positioning system required to permit reconstruction of muon tracks with sufficient precision to meet the astrophysical goals of the experiment. In addition, we are making significant contributions to the design of the database and triggering system to be used. Work has been continuing in other aspects of the study of multiparticle production processes in nuclei. We are participants in a joint US/Japan program to study nuclear interactions at energies two orders of magnitude greater than those of existing accelerators, using balloon-borne emulsion chambers. On one of the flights we found two nuclear interactions of multiplicity over 1000 -- one with a multiplicity of over 2000 and pseudorapidity density {approximately} 800 in the central region. At the statistical level of the JACEE experiment, the frequency of occurrence of such events is orders of magnitude too large. We have continued our ongoing program to study hadronic interactions in emulsions exposed to high energy accelerator beams.

    10. One-dimensional chain of quantum molecule motors as a mathematical physics model for muscle fibers

      NASA Astrophysics Data System (ADS)

      Si, Tie-Yan

      2015-12-01

      A quantum chain model of multiple molecule motors is proposed as a mathematical physics theory for the microscopic modeling of classical force-velocity relation and tension transients in muscle fibers. The proposed model was a quantum many-particle Hamiltonian to predict the force-velocity relation for the slow release of muscle fibers, which has not yet been empirically defined and was much more complicated than the hyperbolic relationships. Using the same Hamiltonian model, a mathematical force-velocity relationship was proposed to explain the tension observed when the muscle was stimulated with an alternative electric current. The discrepancy between input electric frequency and the muscle oscillation frequency could be explained physically by the Doppler effect in this quantum chain model. Further more, quantum physics phenomena were applied to explore the tension time course of cardiac muscle and insect flight muscle. Most of the experimental tension transient curves were found to correspond to the theoretical output of quantum two- and three-level models. Mathematical modeling electric stimulus as photons exciting a quantum three-level particle reproduced most of the tension transient curves of water bug Lethocerus maximus. Project supported by the Fundamental Research Foundation for the Central Universities of China.

    11. Particle Physics in a Season of Change

      SciTech Connect

      Quigg, Chris

      2012-02-01

      A digest of the authors opening remarks at the 2011 Hadron Collider Physics Symposium. I have chosen my title to reflect the transitions we are living through, in particle physics overall and in hadron collider physics in particular. Data-taking has ended at the Tevatron, with {approx} 12 fb{sup -1} of {bar p}p interactions delivered to CDF and D0 at {radical}s = 1.96 TeV. The Large Hadron Collider has registered a spectacular first full-year run, with ATLAS and CMS seeing > 5 fb{sup -1}, LHCb recording {approx} 1 fb{sup -1}, and ALICE logging nearly 5 pb{sup -1} of pp data at {radical}s = 7 TeV, plus a healthy dose of Pb-Pb collisions. The transition to a new energy regime and new realms of instantaneous luminosity exceeding 3.5 x 10{sup 33} cm{sup -2} s{sup -1} has brought the advantage of enhanced physics reach and the challenge of pile-up reaching {approx} 15 interactions per beam crossing. I am happy to record that what the experiments have (not) found so far has roused some of my theoretical colleagues from years of complacency and stimulated them to think anew about what the TeV scale might hold. We theorists have had plenty of time to explore many proposals for electroweak symmetry breaking and for new physics that might lie beyond established knowledge. With so many different theoretical inventions in circulation, it is in the nature of things that most will be wrong. Keep in mind that we learn from what experiment tells us is not there, even if it is uncommon to throw a party for ruling something out. Some non-observations may be especially telling: the persistent absence of flavor-changing neutral currents, for example, seems to me more and more an important clue that we have not yet deciphered. It is natural that the search for the avatar of electroweak symmetry breaking preoccupies participants and spectators alike. But it is essential to conceive the physics opportunities before us in their full richness. I would advocate a three-fold approach

    12. Spacetime alternatives in the quantum mechanics of a relativistic particle

      SciTech Connect

      Whelan, J.T. Isaac Newton Institute for Mathematical Sciences, 20 Clarkson Road, Cambridge, CB3 0EH )

      1994-11-15

      Hartle's generalized quantum mechanics formalism is used to examine spacetime coarse grainings, i.e., sets of alternatives defined with respect to a region extended in time as well as space, in the quantum mechanics of a free relativistic particle. For a simple coarse graining and suitable initial conditions, tractable formulas are found for branch wave functions. Despite the nonlocality of the positive-definite version of the Klein-Gordon inner product, which means that nonoverlapping branches are not sufficient to imply decoherence, some initial conditions are found to give decoherence and allow the consistent assignment of probabilities.

    13. Particle astronomy and particle physics from the moon - The particle observatory

      NASA Technical Reports Server (NTRS)

      Wilson, Thomas L.

      1990-01-01

      Promising experiments from the moon using particle detectors are discussed, noting the advantage of the large flux collecting power Pc offered by the remote, stable environment of a lunar base. An observatory class of particle experiments is presented, based upon proposals at NASA's recent Stanford workshop. They vary from neutrino astronomy, particle astrophysics, and cosmic ray experiments to space physics and fundamental physics experiments such as proton decay and 'table-top' arrays. This research is background-limited on earth, and it is awkward and unrealistic in earth orbit, but is particularly suited for the moon where Pc can be quite large and the instrumentation is not subject to atmospheric erosion as it is (for large t) in low earth orbit.

    14. Research accomplishments and future goals in particle physics

      SciTech Connect

      Whitaker, J.S.

      1990-01-05

      This document presents our proposal to continue the activities of Boston University researchers in eight projects in high energy physics research: Colliding Beams Physics; Accelerator Design Physics; MACRO Project; Proton Decay Project; Theoretical Particle Physics; Muon G-2 Project; and Hadron Collider Physics. The scope of each of these projects is presented in detail in this paper.

    15. The Physical Principles of Particle Detectors.

      ERIC Educational Resources Information Center

      Jones, Goronwy Tudor

      1991-01-01

      Describes the use of a particle detector, an instrument that records the passage of particles through it, to determine the mass of a particle by measuring the particles momentum, speed, and kinetic energy. An appendix discusses the limits on the impact parameter. (MDH)

    16. Design of Quantum Algorithms Using Physics Tools

      DTIC Science & Technology

      2014-06-02

      They asked how entangled the ground state of a FF quantum spin-s chain with nearest - neighbor interactions can be for small values of s. While FF spin-1...investigated chains of ’d’ dimensional quantum spins (qudits) on a line with generic nearest neighbor interactions without translational invariance. They...worked on a wide range of topics with some common themes related by the study of quantum Hamiltonians. Ground state properties of Hamiltonians and the

    17. Time and a physical Hamiltonian for quantum gravity.

      PubMed

      Husain, Viqar; Pawłowski, Tomasz

      2012-04-06

      We present a nonperturbative quantization of general relativity coupled to dust and other matter fields. The dust provides a natural time variable, leading to a physical Hamiltonian with spatial diffeomorphism symmetry. The surprising feature is that the Hamiltonian is not a square root. This property, together with the kinematical structure of loop quantum gravity, provides a complete theory of quantum gravity, and puts applications to cosmology, quantum gravitational collapse, and Hawking radiation within technical reach.

    18. The Second Law and Quantum Physics

      NASA Astrophysics Data System (ADS)

      Bennett, Charles H.

      2008-08-01

      In this talk, I discuss the mystery of the second law and its relation to quantum information. There are many explanations of the second law, mostly satisfactory and not mutually exclusive. Here, I advocate quantum mechanics and quantum information as something that, through entanglement, helps resolve the paradox or the puzzle of the origin of the second law. I will discuss the interpretation called quantum Darwinism and how it helps explain why our world seems so classical, and what it has to say about the permanence or transience of information. And I will discuss a simple model illustrating why systems away from thermal equilibrium tend to be more complicated.

    19. Are quantum-mechanical-like models possible, or necessary, outside quantum physics?

      NASA Astrophysics Data System (ADS)

      Plotnitsky, Arkady

      2014-12-01

      This article examines some experimental conditions that invite and possibly require recourse to quantum-mechanical-like mathematical models (QMLMs), models based on the key mathematical features of quantum mechanics, in scientific fields outside physics, such as biology, cognitive psychology, or economics. In particular, I consider whether the following two correlative features of quantum phenomena that were decisive for establishing the mathematical formalism of quantum mechanics play similarly important roles in QMLMs elsewhere. The first is the individuality and discreteness of quantum phenomena, and the second is the irreducibly probabilistic nature of our predictions concerning them, coupled to the particular character of the probabilities involved, as different from the character of probabilities found in classical physics. I also argue that these features could be interpreted in terms of a particular form of epistemology that suspends and even precludes a causal and, in the first place, realist description of quantum objects and processes. This epistemology limits the descriptive capacity of quantum theory to the description, classical in nature, of the observed quantum phenomena manifested in measuring instruments. Quantum mechanics itself only provides descriptions, probabilistic in nature, concerning numerical data pertaining to such phenomena, without offering a physical description of quantum objects and processes. While QMLMs share their use of the quantum-mechanical or analogous mathematical formalism, they may differ by the roles, if any, the two features in question play in them and by different ways of interpreting the phenomena they considered and this formalism itself. This article will address those differences as well.

    20. Particle physics: CP violation in hyperon decays

      SciTech Connect

      Longo, Michael J.

      2000-10-31

      The primary research activities under this grant were in E871 (HyperCP) at Fermilab, a search for CP violation in hyperon decays which completed data taking in January, 2000. HyperCP is an experiment designed to perform a sensitive search for direct CP violation in the decays of cascade ({Xi}) and {Lambda} hyperons by looking for an asymmetry between particle and antiparticle decay parameters. The experiment is expected to achieve a sensitivity {approx}10{sup -4} in the decay parameters. Standard model predictions for this CP-violating asymmetry range from 0.3 to 5 x 10{sup -4}. A difference between the decay parameters for particle and antiparticle is direct evidence that CP symmetry is violated. A non-zero asymmetry would be the first evidence for CP violation outside of the K{sup o} system. Recent results from KTeV indicate a direct CP violation in K{sup o} decays, which suggests that CP violation will appear in other decays. In addition, we will look at a number of rare hyperon decays involving muons. These probe important new physics topics such as Majorana neutrinos and lepton number violating processes. The latter are of great current interest because new evidence for neutrino oscillations indicate lepton flavor violation does occur. Our data will lead to an improvement in the limits on branching ratios for these processes typically by three to four orders-of-magnitude. The muon detector construction and data resulting from it have been the responsibility of the Michigan group. We are now leading the analysis of the rare muon-related decay modes, and were responsible for the muon system and beam monitor upgrades for the 1999 run.

    1. Methods of Quantum Field Theory in Condensed Matter Physics ---New Perspectives, Extensions and Applications---

      NASA Astrophysics Data System (ADS)

      Umezawa, H.

      Throughout the course of its development in the past four decades quantum field theory has gradually acquired a very rich structure (much richer in fact than it was originally intended) and now provides us with an effective method in the analysis of many diverse areas of physics; condensed matter physics, high energy particle physics general relativity and cosmology are among the more notable examples. Since condensed matter physics deals with those phenomena in which a system of quanta exist together with a variety of macroscopic objects at finite temperature, it may be said to manifest the fundamental properties of quantum field theory in its widest sense. Thus condensed matter physics has served as a powerful motivating force throughout the growth and development of quantum field theory. This process was indeed initiated by the celebrated Matsubara formalism of finite temperature Green's function method. This process is by no means complete since recent developments in many areas of physics demand a more sophisticated understanding with regard to the fundamental nature of quantum field theory. A brief description of this maturing process of quantum field theory in the past, present and prospects for the future will be the main content of this article.

    2. Single particle in quantum gravity and Braunstein-Ghosh-Severini entropy of a spin network

      SciTech Connect

      Rovelli, Carlo; Vidotto, Francesca

      2010-02-15

      Passerini and Severini have recently shown that the Braunstein-Ghosh-Severini (BGS) entropy S{sub {Gamma}}=-Tr[{rho}{sub {Gamma}}log{rho}{sub {Gamma}}] of a certain density matrix {rho}{sub {Gamma}} naturally associated to a graph {Gamma}, is maximized, among all graphs with a fixed number of links and nodes, by regular graphs. We ask if this result can play a role in quantum gravity, and be related to the apparent regularity of the physical geometry of space. We show that in loop quantum gravity the matrix {rho}{sub {Gamma}} is precisely the Hamiltonian operator (suitably normalized) of a nonrelativistic quantum particle interacting with the quantum gravitational field, if we restrict elementary area and volume eigenvalues to a fixed value. This operator provides a spectral characterization of the physical geometry, and can be interpreted as a state describing the spectral information about the geometry available when geometry is measured by its physical interaction with matter. It is then tempting to interpret its BGS entropy S{sub {Gamma}} as a genuine physical entropy: we discuss the appeal and the difficulties of this interpretation.

    3. Two Decades of Mexican Particle Physics at Fermilab

      NASA Astrophysics Data System (ADS)

      Rubinstein, R.

      2003-06-01

      This report is a view from Fermilab of Mexican particle physics at the Laboratory since about 1980; it is not intended to be a history of Mexican particle physics: that topic is outside the expertise of the writer. The period 1980 to the present coincides with the growth of Mexican experimental particle physics from essentially no activity to its current state where Mexican groups take part in experiments at several of the world's major laboratories.

    4. Quantum-Carnot engine for particle confined to cubic potential

      SciTech Connect

      Sutantyo, Trengginas Eka P. Belfaqih, Idrus H. Prayitno, T. B.

      2015-09-30

      Carnot cycle consists of isothermal and adiabatic processes which are reversible. Using analogy in quantum mechanics, these processes can be well explained by replacing variables in classical process with a quantum system. Quantum system which is shown in this paper is a particle that moves under the influence of a cubic potential which is restricted only to the state of the two energy levels. At the end, the efficiency of the system is shown as a function of the width ratio between the initial conditions and the farthest wall while expanding. Furthermore, the system efficiency will be considered 1D and 2D cases. The providing efficiencies are different due to the influence of the degeneration of energy and the degrees of freedom of the system.

    5. Quantum-Carnot engine for particle confined to cubic potential

      NASA Astrophysics Data System (ADS)

      Sutantyo, Trengginas Eka P.; Belfaqih, Idrus H.; Prayitno, T. B.

      2015-09-01

      Carnot cycle consists of isothermal and adiabatic processes which are reversible. Using analogy in quantum mechanics, these processes can be well explained by replacing variables in classical process with a quantum system. Quantum system which is shown in this paper is a particle that moves under the influence of a cubic potential which is restricted only to the state of the two energy levels. At the end, the efficiency of the system is shown as a function of the width ratio between the initial conditions and the farthest wall while expanding. Furthermore, the system efficiency will be considered 1D and 2D cases. The providing efficiencies are different due to the influence of the degeneration of energy and the degrees of freedom of the system.

    6. Teaching and Understanding of Quantum Interpretations in Modern Physics Courses

      ERIC Educational Resources Information Center

      Baily, Charles; Finkelstein, Noah D.

      2010-01-01

      Just as expert physicists vary in their personal stances on interpretation in quantum mechanics, instructors vary on whether and how to teach interpretations of quantum phenomena in introductory modern physics courses. In this paper, we document variations in instructional approaches with respect to interpretation in two similar modern physics…

    7. Role of quantum statistics in multi-particle decay dynamics

      SciTech Connect

      Marchewka, Avi; Granot, Er’el

      2015-04-15

      The role of quantum statistics in the decay dynamics of a multi-particle state, which is suddenly released from a confining potential, is investigated. For an initially confined double particle state, the exact dynamics is presented for both bosons and fermions. The time-evolution of the probability to measure two-particle is evaluated and some counterintuitive features are discussed. For instance, it is shown that although there is a higher chance of finding the two bosons (as oppose to fermions, and even distinguishable particles) at the initial trap region, there is a higher chance (higher than fermions) of finding them on two opposite sides of the trap as if the repulsion between bosons is higher than the repulsion between fermions. The results are demonstrated by numerical simulations and are calculated analytically in the short-time approximation. Furthermore, experimental validation is suggested.

    8. Friction and particle-hole pairs. [in dissipative quantum phenomena

      NASA Technical Reports Server (NTRS)

      Guinea, F.

      1984-01-01

      The effect induced by dissipation on quantum phenomena has recently been considered, taking into account as a starting point a phenomenological Hamiltonian in which the environment is simulated by an appropriately chosen set of harmonic oscillators. It is found that this approach should be adequate to describe the low-energy behavior of a wide class of environments. The present investigation is concerned with an analysis of the case in which the environment is a gas (or liquid) of fermions, and the relevant low-energy excitations are particle-hole pairs. A study is conducted regarding the extent to which the quantum results obtained for harmonic oscillators are also valid in the considered situation. Linear-response theory is used to derive an effective action which describes the motion of an external particle coupled to a normal Fermi fluid.

    9. From Dualism to Unity in Quantum Physics

      NASA Astrophysics Data System (ADS)

      Landé, Alfred

      2016-02-01

      Preface; Introduction; 1. Causality, chance, continuity; 2. States, observables, probabilities; 3. The metric law of probabilities; 4. Quantum dynamics; 5. Quantum fact and fiction; Retrospect. From dualism to unity, from positivism to realism; Appendix 1. Survey of elementary postulates; Appendix 2. Two problems of uniqueness; References; Index.

    10. Finite-time measurement of quantum particle's mean position

      NASA Astrophysics Data System (ADS)

      Liu, Y.; Sokolovski, D.

      2001-01-01

      We analyze nonrelativistic quantum measurement of the time average of the particle's coordinate, X≡t- 1∫t0x(t')dt'. The measurement amplitude is constructed by restricting the Feynman path integral to paths with the required value of X. The resulting decomposition of the Schrödinger wave function determines the type of meter needed to measure X. We show that such meter can be realized as a magnetic moment traveling with the particle in a magnetic field whose magnitude linearly changes with x. Weak and strong measurement regimes are discussed.

    11. Ring particles - Collisional interactions and physical nature

      NASA Technical Reports Server (NTRS)

      Weidenschilling, S. J.; Chapman, C. R.; Davis, D. R.; Greenberg, R.

      1984-01-01

      Attention is given to the properties of, and dynamical processes affecting individual particles of Saturn's rings. Because particles tend to be gravitationally bound when located on the surfaces of larger particles, and since net tidal stresses within the particles are small, particle collisions should produce accretion in Saturn's rings. Rapid accretionary processes within the rings are counterbalanced by tidal disruption of the larger accreted aggregates, which are presently designated 'dynamic ephemeral bodies'. The coefficient of restitution is probably very low, implying that the large particles containing most of the rings' mass are in a monolayer, although the small particles responsible for most of the rings' visible cross section form a layer many particles thick. Kinematic viscosity and interparticle erosive process models should incorporate these properties.

    12. Variance of the Quantum Dwell Time for a Nonrelativistic Particle

      NASA Technical Reports Server (NTRS)

      Hahne, Gerhard

      2012-01-01

      Munoz, Seidel, and Muga [Phys. Rev. A 79, 012108 (2009)], following an earlier proposal by Pollak and Miller [Phys. Rev. Lett. 53, 115 (1984)] in the context of a theory of a collinear chemical reaction, showed that suitable moments of a two-flux correlation function could be manipulated to yield expressions for the mean quantum dwell time and mean square quantum dwell time for a structureless particle scattering from a time-independent potential energy field between two parallel lines in a two-dimensional spacetime. The present work proposes a generalization to a charged, nonrelativistic particle scattering from a transient, spatially confined electromagnetic vector potential in four-dimensional spacetime. The geometry of the spacetime domain is that of the slab between a pair of parallel planes, in particular those defined by constant values of the third (z) spatial coordinate. The mean Nth power, N = 1, 2, 3, . . ., of the quantum dwell time in the slab is given by an expression involving an N-flux-correlation function. All these means are shown to be nonnegative. The N = 1 formula reduces to an S-matrix result published previously [G. E. Hahne, J. Phys. A 36, 7149 (2003)]; an explicit formula for N = 2, and of the variance of the dwell time in terms of the S-matrix, is worked out. A formula representing an incommensurability principle between variances of the output-minus-input flux of a pair of dynamical variables (such as the particle s time flux and others) is derived.

    13. Families of particles with different masses in PT-symmetric quantum field theory.

      PubMed

      Bender, Carl M; Klevansky, S P

      2010-07-16

      An elementary field-theoretic mechanism is proposed that allows one Lagrangian to describe a family of particles having different masses but otherwise similar physical properties. The mechanism relies on the observation that the Dyson-Schwinger equations derived from a Lagrangian can have many different but equally valid solutions. Nonunique solutions to the Dyson-Schwinger equations arise when the functional integral for the Green's functions of the quantum field theory converges in different pairs of Stokes' wedges in complex-field space, and the solutions are physically viable if the pairs of Stokes' wedges are PT symmetric.

    14. Wave-particle duality and uncertainty principle: Phenomenographic categories of description of tertiary physics students' depictions

      NASA Astrophysics Data System (ADS)

      Ayene, Mengesha; Kriek, Jeanne; Damtie, Baylie

      2011-12-01

      Quantum mechanics is often thought to be a difficult subject to understand, not only in the complexity of its mathematics but also in its conceptual foundation. In this paper we emphasize students’ depictions of the uncertainty principle and wave-particle duality of quantum events, phenomena that could serve as a foundation in building an understanding of quantum mechanics. A phenomenographic study was carried out to categorize a picture of students’ descriptions of these key quantum concepts. Data for this study were obtained from a semistructured in-depth interview conducted with undergraduate physics students (N=25) from Bahir Dar, Ethiopia. The phenomenographic data analysis revealed that it is possible to construct three qualitatively different categories to map students’ depictions of the concept wave-particle duality, namely, (1) classical description, (2) mixed classical-quantum description, and (3) quasiquantum description. Similarly, it is proposed that students’ depictions of the concept uncertainty can be described with four different categories of description, which are (1) uncertainty as an extrinsic property of measurement, (2) uncertainty principle as measurement error or uncertainty, (3) uncertainty as measurement disturbance, and (4) uncertainty as a quantum mechanics uncertainty principle. Overall, we found students are more likely to prefer a classical picture of interpretations of quantum mechanics. However, few students in the quasiquantum category applied typical wave phenomena such as interference and diffraction that cannot be explained within the framework classical physics for depicting the wavelike properties of quantum entities. Despite inhospitable conceptions of the uncertainty principle and wave- and particlelike properties of quantum entities in our investigation, the findings presented in this paper are highly consistent with those reported in previous studies. New findings and some implications for instruction and the

    15. The International Particle Physics Outreach Group (ippog):. Aims and Activities

      NASA Astrophysics Data System (ADS)

      Barney, David

      2012-08-01

      The International Particle Physics Outreach Group, IPPOG, is a network of particle physics communication and education experts. IPPOG's principle aim is to maximize the impact of education and outreach efforts related to particle physics through information exchange and the sharing of expertise. IPPOG has initiated several major European and Worldwide activities, such as the "International Particle Physics Masterclasses" where each year thousands of high school students in more than 20 countries come to one of about 120 nearby universities or research centres for a day in order to unravel the mysteries of particle physics. IPPOG has also initiated a global database of education and outreach materials, aimed at supporting other particle physicists and education professionals. The aims and activities of IPPOG will be described, as well as plans to include more countries & laboratories in the network.

    16. Teaching Elementary Particle Physics, Part II

      ERIC Educational Resources Information Center

      Hobson, Art

      2011-01-01

      In order to explain certain features of radioactive beta decay, Wolfgang Pauli suggested in 1930 that the nucleus emitted, in addition to a beta particle, another particle of an entirely new type. The hypothesized particle, dubbed the neutrino, would not be discovered experimentally for another 25 years. It's not easy to detect neutrinos, because…

    17. Atomic physics and quantum optics using superconducting circuits.

      PubMed

      You, J Q; Nori, Franco

      2011-06-29

      Superconducting circuits based on Josephson junctions exhibit macroscopic quantum coherence and can behave like artificial atoms. Recent technological advances have made it possible to implement atomic-physics and quantum-optics experiments on a chip using these artificial atoms. This Review presents a brief overview of the progress achieved so far in this rapidly advancing field. We not only discuss phenomena analogous to those in atomic physics and quantum optics with natural atoms, but also highlight those not occurring in natural atoms. In addition, we summarize several prospective directions in this emerging interdisciplinary field.

    18. Lagrangian Description for Particle Interpretations of Quantum Mechanics: Single-Particle Case

      NASA Astrophysics Data System (ADS)

      Sutherland, Roderick I.

      2015-11-01

      A Lagrangian description is presented which can be used in conjunction with particle interpretations of quantum mechanics. A special example of such an interpretation is the well-known Bohm model. The Lagrangian density introduced here also contains a potential for guiding the particle. The advantages of this description are that the field equations and the particle equations of motion can both be deduced from a single Lagrangian density expression and that conservation of energy and momentum are assured. After being developed in a general form, this Lagrangian formulation is then applied to the special case of the Bohm model as an example. It is thereby demonstrated that such a Lagrangian description is compatible with the predictions of quantum mechanics.

    19. Quantum-like Probabilistic Models Outside Physics

      NASA Astrophysics Data System (ADS)

      Khrennikov, Andrei

      We present a quantum-like (QL) model in that contexts (complexes of e.g. mental, social, biological, economic or even political conditions) are represented by complex probability amplitudes. This approach gives the possibility to apply the mathematical quantum formalism to probabilities induced in any domain of science. In our model quantum randomness appears not as irreducible randomness (as it is commonly accepted in conventional quantum mechanics, e.g. by von Neumann and Dirac), but as a consequence of obtaining incomplete information about a system. We pay main attention to the QL description of processing of incomplete information. Our QL model can be useful in cognitive, social and political sciences as well as economics and artificial intelligence. In this paper we consider in a more detail one special application — QL modeling of brain's functioning. The brain is modeled as a QL-computer.

    20. Test on the Effectiveness of the Sum over Paths Approach in Favoring the Construction of an Integrated Knowledge of Quantum Physics in High School

      ERIC Educational Resources Information Center

      Malgieri, Massimiliano; Onorato, Pasquale; De Ambrosis, Anna

      2017-01-01

      In this paper we present the results of a research-based teaching-learning sequence on introductory quantum physics based on Feynman's sum over paths approach in the Italian high school. Our study focuses on students' understanding of two founding ideas of quantum physics, wave particle duality and the uncertainty principle. In view of recent…

    1. Transnational Quantum: Quantum Physics in India through the Lens of Satyendranath Bose

      NASA Astrophysics Data System (ADS)

      Banerjee, Somaditya

      2016-08-01

      This paper traces the social and cultural dimensions of quantum physics in colonial India where Satyendranath Bose worked. By focusing on Bose's approach towards the quantum and his collaboration with Albert Einstein, I argue that his physics displayed both the localities of doing science in early twentieth century India as well as a cosmopolitan dimension. He transformed the fundamental new concept of the light quantum developed by Einstein in 1905 within the social and political context of colonial India. This cross-pollination of the local with the global is termed here as the locally rooted cosmopolitan nature of Bose's science. The production of new knowledge through quantum statistics by Bose show the co-constructed nature of physics and the transnational nature of the quantum.

    2. Annihilation physics of exotic galactic dark matter particles

      NASA Technical Reports Server (NTRS)

      Stecker, F. W.

      1990-01-01

      Various theoretical arguments make exotic heavy neutral weakly interacting fermions, particularly those predicted by supersymmetry theory, attractive candidates for making up the large amount of unseen gravitating mass in galactic halos. Such particles can annihilate with each other, producing secondary particles of cosmic-ray energies, among which are antiprotons, positrons, neutrinos, and gamma-rays. Spectra and fluxes of these annihilation products can be calculated, partly by making use of positron electron collider data and quantum chromodynamic models of particle production derived therefrom. These spectra may provide detectable signatures of exotic particle remnants of the big bang.

    3. Teaching Quantum Physics in Upper Secondary School in France:

      NASA Astrophysics Data System (ADS)

      Lautesse, Philippe; Vila Valls, Adrien; Ferlin, Fabrice; Héraud, Jean-Loup; Chabot, Hugues

      2015-10-01

      One of the main problems in trying to understand quantum physics is the nature of the referent of quantum theory. This point is addressed in the official French curriculum in upper secondary school. Starting in 2012, after about 20 years of absence, quantum physics has returned to the national program. On the basis of the historical construction of quantum physics, we identify two epistemological positions with respect to this problem: The first one (close to the so-called Copenhagen school) is termed the conservative position and the second one (associated with the work of Bunge and Lévy-Leblond) the innovative position. We then analyze French textbooks used by teachers, in order to reveal the implicit positions adopted. We conclude with the idea that highlighting these epistemological choices can help teachers reflect upon the historical and epistemological roots of quantum physics. Such an analysis can contribute to developing and implementing appropriate teaching sequences for quantum physics. We explore the application of these epistemological positions to Young's paradigmatic experiment using the double slits.

    4. Noisy quantum walks of two indistinguishable interacting particles

      NASA Astrophysics Data System (ADS)

      Siloi, Ilaria; Benedetti, Claudia; Piccinini, Enrico; Piilo, Jyrki; Maniscalco, Sabrina; Paris, Matteo G. A.; Bordone, Paolo

      2017-02-01

      We investigate the dynamics of continuous-time two-particle quantum walks on a one-dimensional noisy lattice. Depending on the initial condition, we show how the interplay between particle indistinguishability and interaction determines distinct propagation regimes. A realistic model for the environment is considered by introducing non-Gaussian noise as time-dependent fluctuations of the tunneling amplitudes between adjacent sites. We observe that the combined effect of particle interaction and fast noise (weak coupling with the environment) provides a faster propagation compared to the noiseless case. This effect can be understood in terms of the band structure of the Hubbard model, and a detailed analysis as a function of both noise and system parameters is presented.

    5. NOON states via a quantum walk of bound particles

      NASA Astrophysics Data System (ADS)

      Compagno, Enrico; Banchi, Leonardo; Gross, Christian; Bose, Sougato

      2017-01-01

      Tight-binding lattice models allow the creation of bound composite objects which, in the strong-interacting regime, are protected against dissociation. We show that a local impurity in the lattice potential can generate a coherent split of an incoming bound particle wave packet which consequently produces a NOON state between the endpoints. This is nontrivial because, when finite lattices are involved, edge-localization effects render challenging their use for nonclassical state generation and information transfer. We derive an effective model to describe the propagation of bound particles in a Bose-Hubbard chain. We introduce local impurities in the lattice potential to inhibit localization effects and to split the propagating bound particle, thus enabling the generation of distant NOON states. We analyze how minimal engineering transfer schemes improve the transfer fidelity and we quantify the robustness to typical decoherence effects in optical lattice implementations. Our scheme potentially has an impact on quantum-enhanced atomic interferometry in a lattice.

    6. New concepts in particle physics from the solution of an old problem

      NASA Astrophysics Data System (ADS)

      Schroer, Bert

      2000-07-01

      Recent ideas on modular localization in local quantum physics are used to clarify the relation between on- and off-shell quantities in particle physics; in particular, the relation between on-shell crossing symmetry and off-shell Einstein causality. Among the collateral results of this new non-perturbative approach are profound relations between crossing symmetry of particle physics and Hawking-Unruh-like thermal aspects (KMS property, entropy attached to horizons) of quantum matter behind causal horizons, aspects which hitherto were exclusively related to Killing horizons in curved spacetime rather than with localization aspects in Minkowski space particle physics. The scope of this modular framework is amazingly wide and ranges from providing a conceptual basis for the d = 1 + 1 bootstrap-formfactor programme for factorizable d = 1 + 1 models to a decomposition theory of quantum field theories in terms of a finite collection of unitarily equivalent chiral conformal theories placed a specified relative position within a common Hilbert space (in d = 1 + 1 a holographic relation and in higher dimensions more like a scanning). The new framework gives a spacetime interpretation to the Zamolodchikov algebra and explains its thermal aspects.

    7. J.J. Sakurai Prize for Theoretical Particle Physics: 40 Years of Lattice QCD

      NASA Astrophysics Data System (ADS)

      Lepage, Peter

      2016-03-01

      Lattice QCD was invented in 1973-74 by Ken Wilson, who passed away in 2013. This talk will describe the evolution of lattice QCD through the past 40 years with particular emphasis on its first years, and on the past decade, when lattice QCD simulations finally came of age. Thanks to theoretical breakthroughs in the late 1990s and early 2000s, lattice QCD simulations now produce the most accurate theoretical calculations in the history of strong-interaction physics. They play an essential role in high-precision experimental studies of physics within and beyond the Standard Model of Particle Physics. The talk will include a non-technical review of the conceptual ideas behind this revolutionary development in (highly) nonlinear quantum physics, together with a survey of its current impact on theoretical and experimental particle physics, and prospects for the future. Work supported by the National Science Foundation.

    8. Simulations of two-particle interactions with 2D quantum walks in time

      SciTech Connect

      Schreiber, A.; Laiho, K.; Silberhorn, C.; Rohde, P. P.; Štefaňak, M.; Potoček, V.; Hamilton, C.; Jex, I.

      2014-12-04

      We present the experimental implementation of a quantum walk on a two-dimensional lattice and show how to employ the optical system to simulate the quantum propagation of two interacting particles. Our quantum walk in time transfers the spatial spread of a quantum walk into the time domain, which guarantees a high stability and scalability of the setup. We present with our device quantum walks over 12 steps on a 2D lattice. By changing the properties of the driving quantum coin, we investigate different kinds of two-particle interactions and reveal their impact on the occurring quantum propagation.

    9. Multiple particle production processes in the light'' of quantum optics

      SciTech Connect

      Friedlander, E.M.

      1990-09-01

      Ever since the observation that high-energy nuclear active'' cosmic-ray particles create bunches of penetrating particles upon hitting targets, a controversy has raged about whether these secondaries are created in a single act'' or whether many hadrons are just the result of an intra-nuclear cascade, yielding one meson in every step. I cannot escape the impression that: the latter kind of model appeals naturally as a consequence of an innate bio-morphism in our way of thinking and that in one guise or another it has tenaciously survived to this day, also for hadron-hadron collisions, via multi-peripheral models to the modern parton shower approach. Indeed, from the very beginning of theoretical consideration of multiparticle production, the possibility of many particles arising from a single hot'' system has been explored, with many fruitful results, not the least of which are the s{sup 1/4} dependence of the mean produced particle multiplicity and the thermal'' shape of the P{sub T} spectra. An important consequence of the thermodynamical-hydrodynamical models is that particle emission is treated in analogy to black-body radiation, implying for the secondaries a set of specific Quantum-Statistical properties, very similar to those observed in quantum optics. From here on I shall try to review a number of implications and applications of this QS analogy in the study of multiplicity distributions of the produced secondaries. I will touch only in passing another very important topic of this class, the Bose-Einstein two-particle correlations.

    10. CCDM model from quantum particle creation: constraints on dark matter mass

      SciTech Connect

      Jesus, J.F.; Pereira, S.H. E-mail: shpereira@gmail.com

      2014-07-01

      In this work the results from the quantum process of matter creation have been used in order to constrain the mass of the dark matter particles in an accelerated Cold Dark Matter model (Creation Cold Dark Matter, CCDM). In order to take into account a back reaction effect due to the particle creation phenomenon, it has been assumed a small deviation ε for the scale factor in the matter dominated era of the form t{sup 2/3+ε}. Based on recent H(z) data, the best fit values for the mass of dark matter created particles and the ε parameter have been found as m = 1.6× 10{sup 3} GeV, restricted to a 68.3% c.l. interval of 1.5 < m < 6.3× 10{sup 7}) GeV and ε = -0.250{sup +0.15}{sub -0.096} at 68.3% c.l. For these best fit values the model correctly recovers a transition from decelerated to accelerated expansion and admits a positive creation rate near the present era. Contrary to recent works in CCDM models where the creation rate was phenomenologically derived, here we have used a quantum mechanical result for the creation rate of real massive scalar particles, given a self consistent justification for the physical process. This method also indicates a possible solution to the so called ''dark degeneracy'', where one can not distinguish if it is the quantum vacuum contribution or quantum particle creation which accelerates the Universe expansion.

    11. Quantum dot-containing polymer particles with thermosensitive fluorescence

      NASA Astrophysics Data System (ADS)

      Generalova, Alla N.; Oleinikov, Vladimir A.; Sukhanova, Alyona; Artemyev, Mikhail V.; Zubov, Vitaly P.; Nabiev, Igor

      2012-10-01

      In the past decades, increasing attention has been paid to the preparation of "smart" functionalized polymer particles reversibly responding to slight environmental changes, such as variations in temperature, pH, and ionic strength. The composite polymer particles consisting of a solid poly(acrolein-co-styrene) core and a poly(N-vinylcaprolactam) (PVCL) polymer shell doped with CdSe/ZnS semiconductor quantum dots (QDs) were prepared. The thermosensitive response of the composite particles was observed as a decrease in their hydrodynamic diameter upon heating above the lower critical solution temperature of the thermosensitive PVCL polymer used as a shell. Embedding QDs in the PVCL shell makes it possible to obtain particles whose fluorescence is sensitive to temperature changes. The temperature-dependent fluorescence of particles was determined by reversible variation of the distances between QDs in the PVCL shell as a result of temperature-driven conformational changes in this polymer. In addition, these particles can be used as carriers of biomolecule (e.g., bovine serum albumin, BSA) characterized by reversibly temperature-dependent fluorescence, which can serve as the basis for optical detection methods in bioassays, such as the measurement of local temperature in nanovolumes, biosensing, etc.

    12. Quantum-behaved particle swarm optimization: analysis of individual particle behavior and parameter selection.

      PubMed

      Sun, Jun; Fang, Wei; Wu, Xiaojun; Palade, Vasile; Xu, Wenbo

      2012-01-01

      Quantum-behaved particle swarm optimization (QPSO), motivated by concepts from quantum mechanics and particle swarm optimization (PSO), is a probabilistic optimization algorithm belonging to the bare-bones PSO family. Although it has been shown to perform well in finding the optimal solutions for many optimization problems, there has so far been little analysis on how it works in detail. This paper presents a comprehensive analysis of the QPSO algorithm. In the theoretical analysis, we analyze the behavior of a single particle in QPSO in terms of probability measure. Since the particle's behavior is influenced by the contraction-expansion (CE) coefficient, which is the most important parameter of the algorithm, the goal of the theoretical analysis is to find out the upper bound of the CE coefficient, within which the value of the CE coefficient selected can guarantee the convergence or boundedness of the particle's position. In the experimental analysis, the theoretical results are first validated by stochastic simulations for the particle's behavior. Then, based on the derived upper bound of the CE coefficient, we perform empirical studies on a suite of well-known benchmark functions to show how to control and select the value of the CE coefficient, in order to obtain generally good algorithmic performance in real world applications. Finally, a further performance comparison between QPSO and other variants of PSO on the benchmarks is made to show the efficiency of the QPSO algorithm with the proposed parameter control and selection methods.

    13. Two decades of Mexican particle physics at Fermilab

      SciTech Connect

      Roy Rubinstein

      2002-12-03

      This report is a view from Fermilab of Mexican particle physics at the Laboratory since about 1980; it is not intended to be a history of Mexican particle physics: that topic is outside the expertise of the writer. The period 1980 to the present coincides with the growth of Mexican experimental particle physics from essentially no activity to its current state where Mexican groups take part in experiments at several of the world's major laboratories. Soon after becoming Fermilab director in 1979, Leon Lederman initiated a program to encourage experimental physics, especially experimental particle physics, in Latin America. At the time, Mexico had significant theoretical particle physics activity, but none in experiment. Following a visit by Lederman to UNAM in 1981, a conference ''Panamerican Symposium on Particle Physics and Technology'' was held in January 1982 at Cocoyoc, Mexico, with about 50 attendees from Europe, North America, and Latin America; these included Lederman, M. Moshinsky, J. Flores, S. Glashow, J. Bjorken, and G. Charpak. Among the conference outcomes were four subsequent similar symposia over the next decade, and a formal Fermilab program to aid Latin American physics (particularly particle physics); it also influenced a decision by Mexican physicist Clicerio Avilez to switch from theoretical to experimental particle physics. The first physics collaboration between Fermilab and Mexico was in particle theory. Post-docs Rodrigo Huerta and Jose Luis Lucio spent 1-2 years at Fermilab starting in 1981, and other theorists (including Augusto Garcia, Arnulfo Zepeda, Matias Moreno and Miguel Angel Perez) also spent time at the Laboratory in the 1980s.

    14. Pre-Service Physics Teachers' Comprehension of Quantum Mechanical Concepts

      ERIC Educational Resources Information Center

      Didis, Nilufer; Eryilmaz, Ali; Erkoc, Sakir

      2010-01-01

      When quantum theory caused a paradigm shift in physics, it introduced difficulties in both learning and teaching of physics. Because of its abstract, counter-intuitive and mathematical structure, students have difficulty in learning this theory, and instructors have difficulty in teaching the concepts of the theory. This case study investigates…

    15. Making the Transition from Classical to Quantum Physics

      ERIC Educational Resources Information Center

      Dutt, Amit

      2011-01-01

      This paper reports on the nature of the conceptual understandings developed by Year 12 Victorian Certificate of Education (VCE) physics students as they made the transition from the essentially deterministic notions of classical physics, to interpretations characteristic of quantum theory. The research findings revealed the fact that the…

    16. Designing learning environments to teach interactive Quantum Physics

      NASA Astrophysics Data System (ADS)

      Gómez Puente, Sonia M.; Swagten, Henk J. M.

      2012-10-01

      This study aims at describing and analysing systematically an interactive learning environment designed to teach Quantum Physics, a second-year physics course. The instructional design of Quantum Physics is a combination of interactive lectures (using audience response systems), tutorials and self-study in unit blocks, carried out with small groups. Individual formative feedback was introduced as a rapid assessment tool to provide an overview on progress and identify gaps by means of questioning students at three levels: conceptual; prior knowledge; homework exercises. The setup of Quantum Physics has been developed as a result of several loops of adjustments and improvements from a traditional-like type of teaching to an interactive classroom. Results of this particular instructional arrangement indicate significant gains in students' achievements in comparison with the traditional structure of this course, after recent optimisation steps such as the implementation of an individual feedback system.

    17. PARTICLE PHYSICS: CERN Collider Glimpses Supersymmetry--Maybe.

      PubMed

      Seife, C

      2000-07-14

      Last week, particle physicists at the CERN laboratory in Switzerland announced that by smashing together matter and antimatter in four experiments, they detected an unexpected effect in the sprays of particles that ensued. The anomaly is subtle, and physicists caution that it might still be a statistical fluke. If confirmed, however, it could mark the long-sought discovery of a whole zoo of new particles--and the end of a long-standing model of particle physics.

    18. The Bondons: The Quantum Particles of the Chemical Bond

      PubMed Central

      Putz, Mihai V.

      2010-01-01

      By employing the combined Bohmian quantum formalism with the U(1) and SU(2) gauge transformations of the non-relativistic wave-function and the relativistic spinor, within the Schrödinger and Dirac quantum pictures of electron motions, the existence of the chemical field is revealed along the associate bondon particle B̶ characterized by its mass (mB̶), velocity (vB̶), charge (eB̶), and life-time (tB̶). This is quantized either in ground or excited states of the chemical bond in terms of reduced Planck constant ħ, the bond energy Ebond and length Xbond, respectively. The mass-velocity-charge-time quaternion properties of bondons’ particles were used in discussing various paradigmatic types of chemical bond towards assessing their covalent, multiple bonding, metallic and ionic features. The bondonic picture was completed by discussing the relativistic charge and life-time (the actual zitterbewegung) problem, i.e., showing that the bondon equals the benchmark electronic charge through moving with almost light velocity. It carries negligible, although non-zero, mass in special bonding conditions and towards observable femtosecond life-time as the bonding length increases in the nanosystems and bonding energy decreases according with the bonding length-energy relationship Ebond[kcal/mol]×Xbond[A0]=182019, providing this way the predictive framework in which the B̶ particle may be observed. Finally, its role in establishing the virtual states in Raman scattering was also established. PMID:21151435

    19. Path Sampling Methods for Enzymatic Quantum Particle Transfer Reactions.

      PubMed

      Dzierlenga, M W; Varga, M J; Schwartz, S D

      2016-01-01

      The mechanisms of enzymatic reactions are studied via a host of computational techniques. While previous methods have been used successfully, many fail to incorporate the full dynamical properties of enzymatic systems. This can lead to misleading results in cases where enzyme motion plays a significant role in the reaction coordinate, which is especially relevant in particle transfer reactions where nuclear tunneling may occur. In this chapter, we outline previous methods, as well as discuss newly developed dynamical methods to interrogate mechanisms of enzymatic particle transfer reactions. These new methods allow for the calculation of free energy barriers and kinetic isotope effects (KIEs) with the incorporation of quantum effects through centroid molecular dynamics (CMD) and the full complement of enzyme dynamics through transition path sampling (TPS). Recent work, summarized in this chapter, applied the method for calculation of free energy barriers to reaction in lactate dehydrogenase (LDH) and yeast alcohol dehydrogenase (YADH). We found that tunneling plays an insignificant role in YADH but plays a more significant role in LDH, though not dominant over classical transfer. Additionally, we summarize the application of a TPS algorithm for the calculation of reaction rates in tandem with CMD to calculate the primary H/D KIE of YADH from first principles. We found that the computationally obtained KIE is within the margin of error of experimentally determined KIEs and corresponds to the KIE of particle transfer in the enzyme. These methods provide new ways to investigate enzyme mechanism with the inclusion of protein and quantum dynamics.

    20. Quantum physics of simple optical instruments

      NASA Astrophysics Data System (ADS)

      Leonhardt, Ulf

      2003-07-01

      Simple optical instruments are linear optical networks where the incident light modes are turned into equal numbers of outgoing modes by linear transformations. For example, such instruments are beam splitters, multiports, interferometers, fibre couplers, polarizers, gravitational lenses, parametric amplifiers, phase-conjugating mirrors and also black holes. The paper develops the quantum theory of simple optical instruments and applies the theory to a few characteristic situations, to the splitting and interference of photons and to the manifestation of Einstein-Podolsky-Rosen correlations in parametric downconversion. How to model irreversible devices such as absorbers and amplifiers is also shown. Finally, the paper develops the theory of Hawking radiation for a simple optical black hole. The paper is intended as a primer, as a nearly self-consistent tutorial. The reader should be familiar with basic quantum mechanics and statistics, and perhaps with optics and some elementary field theory. The quantum theory of light in dielectrics serves as the starting point and, in the concluding section, as a guide to understand quantum black holes.

    1. Teaching Elementary Particle Physics, Part II

      NASA Astrophysics Data System (ADS)

      Hobson, Art

      2011-03-01

      In order to explain certain features of radioactive beta decay, Wolfgang Pauli suggested in 1930 that the nucleus emitted, in addition to a beta particle, another particle of an entirely new type. The hypothesized particle, dubbed the neutrino, would not be discovered experimentally for another 25 years. It's not easy to detect neutrinos, because they respond to neither the EM force nor the strong force. For example, the mean free path (average penetration distance before it interacts) of a typical beta-decay neutrino moving through solid lead is about 1.5 light years! Enrico Fermi argued that neutrinos indicated a new force was at work. During the 1930s, he quickly adapted ideas from the developing new theory of QED to this new force, dubbed the weak force. Fermi's theory was able to predict the half-lives of beta-emitting nuclei and the range of energies of the emitted beta particles.

    2. Particle physics. Positrons ride the wave

      SciTech Connect

      Piot, Philippe

      2015-08-26

      Here, experiments reveal that positrons — the antimatter equivalents of electrons — can be rapidly accelerated using a plasma wave. The findings pave the way to high-energy electron–positron particle colliders.

    3. Variance of the quantum dwell time for a nonrelativistic particle

      SciTech Connect

      Hahne, G. E.

      2013-01-15

      Munoz, Seidel, and Muga [Phys. Rev. A 79, 012108 (2009)], following an earlier proposal by Pollak and Miller [Phys. Rev. Lett. 53, 115 (1984)] in the context of a theory of a collinear chemical reaction, showed that suitable moments of a two-flux correlation function could be manipulated to yield expressions for the mean quantum dwell time and mean square quantum dwell time for a structureless particle scattering from a time-independent potential energy field between two parallel lines in a two-dimensional spacetime. The present work proposes a generalization to a charged, nonrelativistic particle scattering from a transient, spatially confined electromagnetic vector potential in four-dimensional spacetime. The geometry of the spacetime domain is that of the slab between a pair of parallel planes, in particular, those defined by constant values of the third (z) spatial coordinate. The mean Nth power, N= 1, 2, 3, Horizontal-Ellipsis , of the quantum dwell time in the slab is given by an expression involving an N-flux-correlation function. All these means are shown to be nonnegative. The N= 1 formula reduces to an S-matrix result published previously [G. E. Hahne, J. Phys. A 36, 7149 (2003)]; an explicit formula for N= 2, and of the variance of the dwell time in terms of the S-matrix, is worked out. A formula representing an incommensurability principle between variances of the output-minus-input flux of a pair of dynamical variables (such as the particle's time flux and others) is derived.

    4. Particle physics meets cosmology - The search for decaying neutrinos

      NASA Technical Reports Server (NTRS)

      Henry, R. C.

      1982-01-01

      The fundamental physical implications of the possible detection of massive neutrinos are discussed, with an emphasis on the Grand Unified Theories (GUTs) of matter. The Newtonian and general-relativistic pictures of the fundamental forces are compared, and the reduction of electromagnetic and weak forces to one force in the GUTs is explained. The cosmological consequences of the curved-spacetime gravitation concept are considered. Quarks, leptons, and neutrinos are characterized in a general treatment of elementary quantum mechanics. The universe is described in terms of quantized fields, the noninteractive 'particle' fields and the force fields, and cosmology becomes the study of the interaction of gravitation with the other fields, of the 'freezing out' of successive fields with the expansion and cooling of the universe. While the visible universe is the result of the clustering of the quark and electron fields, the distribution of the large number of quanta in neutrino field, like the mass of the neutrino, are unknown. Cosmological models which attribute anomalies in the observed motions of galaxies and stars to clusters or shells of massive neutrinos are shown to be consistent with a small but nonzero neutrino mass and a universe near the open/closed transition point, but direct detection of the presence of massive neutrinos by the UV emission of their decay is required to verify these hypotheses.

    5. A Reconfigurable Instrument System for Nuclear and Particle Physics Experiments

      NASA Astrophysics Data System (ADS)

      Sang, Ziru; Li, Feng; Jiang, Xiao; Jin, Ge

      2014-04-01

      We developed a reconfigurable nuclear instrument system (RNIS) that could satisfy the requirements of diverse nuclear and particle physics experiments, and the inertial confinement fusion diagnostic. Benefiting from the reconfigurable hardware structure and digital pulse processing technology, RNIS shakes off the restrictions of cumbersome crates and miscellaneous modules. It retains all the advantages of conventional nuclear instruments and is more flexible and portable. RNIS is primarily composed of a field programmable hardware board and relevant PC software. Separate analog channels are designed to provide different functions, such as amplifiers, ADC, fast discriminators and Schmitt discriminators for diverse experimental purposes. The high-performance field programmable gate array could complete high-precision time interval measurement, histogram accumulation, counting, and coincidence anticoincidence measurement. To illustrate the prospects of RNIS, a series of applications to the experiments are described in this paper. The first, for which RNIS was originally developed, involves nuclear energy spectrum measurement with a scintillation detector and photomultiplier. The second experiment applies RNIS to a G-M tube counting experiment, and in the third, it is applied to a quantum communication experiment through reconfiguration.

    6. Recovering the quantum formalism from physically realist axioms

      NASA Astrophysics Data System (ADS)

      Auffèves, Alexia; Grangier, Philippe

      2017-03-01

      We present a heuristic derivation of Born’s rule and unitary transforms in Quantum Mechanics, from a simple set of axioms built upon a physical phenomenology of quantization. This approach naturally leads to the usual quantum formalism, within a new realistic conceptual framework that is discussed in details. Physically, the structure of Quantum Mechanics appears as a result of the interplay between the quantized number of “modalities” accessible to a quantum system, and the continuum of “contexts” that are required to define these modalities. Mathematically, the Hilbert space structure appears as a consequence of a specific “extra-contextuality” of modalities, closely related to the hypothesis of Gleason’s theorem, and consistent with its conclusions.

    7. The Oxford Questions on the foundations of quantum physics.

      PubMed

      Briggs, G A D; Butterfield, J N; Zeilinger, A

      2013-09-08

      The twentieth century saw two fundamental revolutions in physics-relativity and quantum. Daily use of these theories can numb the sense of wonder at their immense empirical success. Does their instrumental effectiveness stand on the rock of secure concepts or the sand of unresolved fundamentals? Does measuring a quantum system probe, or even create, reality or merely change belief? Must relativity and quantum theory just coexist or might we find a new theory which unifies the two? To bring such questions into sharper focus, we convened a conference on Quantum Physics and the Nature of Reality. Some issues remain as controversial as ever, but some are being nudged by theory's secret weapon of experiment.

    8. Recovering the quantum formalism from physically realist axioms

      PubMed Central

      Auffèves, Alexia; Grangier, Philippe

      2017-01-01

      We present a heuristic derivation of Born’s rule and unitary transforms in Quantum Mechanics, from a simple set of axioms built upon a physical phenomenology of quantization. This approach naturally leads to the usual quantum formalism, within a new realistic conceptual framework that is discussed in details. Physically, the structure of Quantum Mechanics appears as a result of the interplay between the quantized number of “modalities” accessible to a quantum system, and the continuum of “contexts” that are required to define these modalities. Mathematically, the Hilbert space structure appears as a consequence of a specific “extra-contextuality” of modalities, closely related to the hypothesis of Gleason’s theorem, and consistent with its conclusions. PMID:28256539

    9. Time evolution of decay of two identical quantum particles

      SciTech Connect

      Garcia-Calderon, Gaston; Mendoza-Luna, Luis Guillermo

      2011-09-15

      An analytical solution for the time evolution of decay of two identical noninteracting quantum particles seated initially within a potential of finite range is derived using the formalism of resonant states. It is shown that the wave function, and hence also the survival and nonescape probabilities, for factorized symmetric and entangled symmetric or antisymmetric initial states evolve in a distinctive form along the exponentially decaying and nonexponential regimes. Our findings show the influence of the Pauli exclusion principle on decay. We exemplify our results by solving exactly the s-wave {delta} shell potential model.

    10. Time fluctuations in isolated quantum systems of interacting particles.

      PubMed

      Zangara, Pablo R; Dente, Axel D; Torres-Herrera, E J; Pastawski, Horacio M; Iucci, Aníbal; Santos, Lea F

      2013-09-01

      Numerically, we study the time fluctuations of few-body observables after relaxation in isolated dynamical quantum systems of interacting particles. Our results suggest that they decay exponentially with system size in both regimes, integrable and chaotic. The integrable systems considered are solvable with the Bethe ansatz and have a highly nondegenerate spectrum. This is in contrast with integrable Hamiltonians mappable to noninteracting ones. We show that the coefficient of the exponential decay depends on the level of delocalization of the initial state with respect to the energy shell.

    11. Particle Physics Meets Cosmology -- The Search for Decaying Neutrinos.

      ERIC Educational Resources Information Center

      Henry, Richard C.

      1982-01-01

      Detection of neutrino decay may have profound consequences for both particle physics and cosmology, providing a deep connection between physics of the very large and physics of the very small. Describes this link and discusses the nature and status of the search for decaying neutrinos. (Author/JN)

    12. Particle Size, Surface Coating, and PEGylation Influence the Biodistribution of Quantum Dots in Living Mice

      PubMed Central

      Schipper, Meike L.; Iyer, Gopal; Koh, Ai Leen; Cheng, Zhen; Ebenstein, Yuval; Aharoni, Assaf; Keren, Shay; Bentolila, Laurent A.; Li, Jianquing; Rao, Jianghong; Chen, Xiaoyuan; Banin, Uri; Wu, Anna M.; Sinclair, Robert; Weiss, Shimon

      2011-01-01

      This study evaluates the influence of particle size, PEGylation, and surface coating on the quantitative biodistribution of near-infrared-emitting quantum dots (QDs) in mice. Polymer- or peptide-coated 64Cu-labeled QDs 2 or 12 nm in diameter, with or without polyethylene glycol (PEG) of molecular weight 2000, are studied by serial micropositron emission tomography imaging and region-of-interest analysis, as well as transmission electron microscopy and inductively coupled plasma mass spectrometry. PEGylation and peptide coating slow QD uptake into the organs of the reticuloendothelial system (RES), liver and spleen, by a factor of 6–9 and 2–3, respectively. Small particles are in part renally excreted. Peptide-coated particles are cleared from liver faster than physical decay alone would suggest. Renal excretion of small QDs and slowing of RES clearance by PEGylation or peptide surface coating are encouraging steps toward the use of modified QDs for imaging living subjects. PMID:19051182

    13. The physical principles of quantum mechanics. A critical review

      NASA Astrophysics Data System (ADS)

      Strocchi, F.

      2012-01-01

      The standard presentation of the principles of quantum mechanics is critically reviewed both from the experimental/operational point and with respect to the request of mathematical consistency and logical economy. A simpler and more physically motivated formulation is discussed. The existence of non commuting observables, which characterizes quantum mechanics with respect to classical mechanics, is related to operationally testable complementarity relations, rather than to uncertainty relations. The drawbacks of Dirac argument for canonical quantization are avoided by a more geometrical approach.

    14. Precision measurement for particle physics and cosmology

      NASA Astrophysics Data System (ADS)

      Graham, Peter

      2017-01-01

      Axions and other light particles are strongly motivated. For example, the axion is the crucial element in the recently proposed solution to the hierarchy problem using dynamical relaxation in the early universe. However, such particles are challenging to search for experimentally. Precision measurement technologies such as atom interferometry, nuclear magnetic resonance, high precision magnetometry, and torsion balances allow novel, highly sensitive experiments for direct detection of such light dark matter and of gravitational waves. Thus precision measurement technologies open new avenues for probing the origin and composition of the universe.

    15. MEASUREMENTS OF BLACK CARBON PARTICLES CHEMICAL, PHYSICAL, AND OPTICAL PROPERTIES

      SciTech Connect

      Onasch, T.B.; Sedlacek, A.; Cross, E. S.; Davidovits, P.; Worsnop, D. R.; Ahern, A.; Lack, D. A.; Cappa, C. D.; Trimborn, A.; Freedman, A.; Olfert, J. S.; Jayne, J. T.; Massoli, P.; Williams, L. R.; Mazzoleni, C.; Schwarz, J. P.; Thornhill, D. A.; Slowik, J. G.; Kok, G. L.; Brem, B. T.; Subramanian, R.; Spackman, J. R.; Freitag, S.; and Dubey, M. K.

      2009-12-14

      Accurate measurements of the chemical, physical, and optical properties of aerosol particles containing black carbon are necessary to improve current estimates of the radiative forcing in the atmosphere. A collaborative research effort between Aerodyne Research, Inc. and Boston College has focused on conducting field and laboratory experiments on carbonaceous particles and the development and characterization of new particulate instrumentation. This presentation will focus on the chemical, physical, and optical properties of black carbon particles measured in the laboratory in order to understand the effects of atmospheric processing on black carbon particles. Results from a three-week study during July 2008 of mass- and optical-based black carbon measurements will be presented. The project utilized the Boston College laboratory flame apparatus and aerosol conditioning and characterization equipment. A pre-mixed flat flame burner operating at controlled fuel-to-air ratios produced stable and reproducible concentrations of soot particles with known sizes, morphologies, and chemical compositions. In addition, other black carbon particle types, including fullerene soot, glassy carbon spheres, oxidized flame soot, Regal black, and Aquadag, were also atomized, size selected, and sampled. The study covered an experimental matrix that systematically selected particle mobility size (30 to 300 nm) and black carbon particle mass, particle number concentration, particle shape (dynamic shape factor and fractal dimension), and particle chemistry and density (changed via coatings). Particles were coated with a measured thickness (few nm to {approx}150 nm) of sulfuric acid or bis (2-ethylhexyl) sebacate and passed through a thermal denuder to remove the coatings. Highlights of the study to be presented include: (1) Characterization of the chemical and physical properties of various types of black carbon particles, (2) Mass specific absorption measurements as a function of fuel

    16. Quantum, cyclic, and particle-exchange heat engines

      NASA Astrophysics Data System (ADS)

      Humphrey, T. E.; Linke, H.

      2005-10-01

      Differences between the thermodynamic behavior of the three-level amplifier (a quantum heat engine based on a thermally pumped laser) and the classical Carnot cycle are usually attributed to the essentially quantum or discrete nature of the former. Here we provide examples of a number of classical and semiclassical heat engines, such as thermionic, thermoelectric and photovoltaic devices, which all utilize the same thermodynamic mechanism for achieving reversibility as the three-level amplifier, namely isentropic (but non-isothermal) particle transfer between hot and cold reservoirs. This mechanism is distinct from the isothermal heat transfer required to achieve reversibility in cyclic engines such as the Carnot, Otto or Brayton cycles. We point out that some of the qualitative differences previously uncovered between the three-level amplifier and the Carnot cycle may be attributed to the fact that they are not the same ‘type’ of heat engine, rather than to the quantum nature of the three-level amplifier per se.

    17. Spectral statistics for the evolution operator of a quantum particle showing chaotic diffusion of the coordinate

      SciTech Connect

      Kolovsky, A.R.

      1997-08-01

      We study the spectral properties of the evolution operator of a quantum particle subject to a space-periodic time-dependent potential. Two qualitatively different regimes of the system dynamics are compared: case (i), when the spreading of the wave packet is asymptotically ballistic; and case (ii), when the wave packet spreads diffusively. As time increases, the spectrum is shown to approach Poisson statistics in case (i) and circular unitary ensemble statistics in case (ii). A scaling relation for the velocity and curvature distributions of the spectral bands are found. {copyright} {ital 1997} {ital The American Physical Society}

    18. The Qubit as Key to Quantum Physics Part II: Physical Realizations and Applications

      NASA Astrophysics Data System (ADS)

      Dür, Wolfgang; Heusler, Stefan

      2016-03-01

      Using the simplest possible quantum system—the qubit—the fundamental concepts of quantum physics can be introduced. This highlights the common features of many different physical systems, and provides a unifying framework when teaching quantum physics at the high school or introductory level. In a previous TPT article and in a separate paper posted online, we introduced catchy visualizations of the qubit based on the Bloch sphere or just the unit circle (see also Refs. 3-8 for other approaches highlighting the importance of the qubit). These visualizations open the way to understand basic ideas of quantum physics even without knowledge of the underlying mathematical formalism. In addition, simple mathematics can be introduced to describe the qubit as an abstract object and basic unit of quantum information. This generalizes the digital bit as a basic unit of classical information. The proposed visualizations can be used even at the high school level, while the mathematical explanations are of importance when teaching quantum physics at the undergraduate university level. This approach provides a unified framework to introduce common features of all quantum systems, such as the stochastic behavior and state change of a superposition state under measurement.

    19. Uses of particle identification for supercollider physics

      SciTech Connect

      Quigg, C.

      1989-05-01

      I summarize the basic characteristics of the Superconducting Super Collider and describe the experimental environment of its high- luminosity interaction regions. I then review some of the discovery possibilities opened by the SSC, with special attention to the advantages conferred by particle identification. 16 refs., 8 figs.

    20. Local energy and power in many-particle quantum systems driven by an external electrical field

      NASA Astrophysics Data System (ADS)

      Albareda, Guillermo; Traversa, Fabio Lorenzo; Oriols, Xavier

      2016-05-01

      We derive expressions for the expectation values of the local energy and the local power for a many-particle system of (scalar) charged particles interacting with an external electrical field. In analogy with the definition of the (local) current probability density, we construct a local energy operator such that the time-rate of change of its expectation value provides information on the spatial distribution of power. Results are presented as functions of an arbitrarily small volume Ω , and physical insights are discussed by means of the quantum hydrodynamical representation of the wavefunction, which is proven to allow for a clear-cut separation into contributions with and without classical correspondence. Quantum features of the local power are mainly manifested through the presence of non-local sources/sinks of power and through the action of forces with no classical counterpart. Many-particle classical-like effects arise in the form of current-force correlations and through the inflow/outflow of energy across the boundaries of the volume Ω . Interestingly, all these intriguing features are only reflected in the expression of the local power when the volume Ω is finite. Otherwise, for closed systems with Ω \\to ∞ , we recover a classical-like single-particle expression.

    1. Quantum Mechanics for Beginning Physics Students

      ERIC Educational Resources Information Center

      Schneider, Mark B.

      2010-01-01

      The past two decades of attention to introductory physics education has emphasized enhanced development of conceptual understanding to accompany calculational ability. Given this, it is surprising that current texts continue to rely on the Bohr model to develop a flawed intuition, and introduce correct atomic physics on an ad hoc basis. For…

    2. Effective theories and thresholds in particle physics

      SciTech Connect

      Gaillard, M.K.

      1991-06-07

      The role of effective theories in probing a more fundamental underlying theory and in indicating new physics thresholds is discussed, with examples from the standard model and more speculative applications to superstring theory. 38 refs.

    3. American particle and nuclear physics planning

      SciTech Connect

      Montgomery, Hugh E.

      2014-10-01

      In the United States the planning process relevant to future deep inelastic scattering involves both the high energy physics and nuclear physics funding and the two communities. In Canada there is no such split between the communities. Within the past two years there have been several planning initiatives and there may be more to come. We review the current status of both the planning and the plans.

    4. Elementary particle physics and high energy phenomena

      SciTech Connect

      Barker, A.R.; Cumalat, J.P.; de Alwis, S.P.; DeGrand, T.A.; Ford, W.T.; Mahanthappa, K.T.; Nauenberg, U.; Rankin, P.; Smith, J.G.

      1992-06-01

      This report discusses the following research in high energy physics: the properties of the z neutral boson with the SLD detector; the research and development program for the SDC muon detector; the fixed-target k-decay experiments; the Rocky Mountain Consortium for HEP; high energy photoproduction of states containing heavy quarks; and electron-positron physics with the CLEO II and Mark II detectors. (LSP).

    5. Decision theory and information propagation in quantum physics

      NASA Astrophysics Data System (ADS)

      Forrester, Alan

      In recent papers, Zurek [(2005). Probabilities from entanglement, Born's rule p k =| ψ k | 2 from entanglement. Physical Review A, 71, 052105] has objected to the decision-theoretic approach of Deutsch [(1999) Quantum theory of probability and decisions. Proceedings of the Royal Society of London A, 455, 3129-3137] and Wallace [(2003). Everettian rationality: defending Deutsch's approach to probability in the Everett interpretation. Studies in History and Philosophy of Modern Physics, 34, 415-438] to deriving the Born rule for quantum probabilities on the grounds that it courts circularity. Deutsch and Wallace assume that the many worlds theory is true and that decoherence gives rise to a preferred basis. However, decoherence arguments use the reduced density matrix, which relies upon the partial trace and hence upon the Born rule for its validity. Using the Heisenberg picture and quantum Darwinism-the notion that classical information is quantum information that can proliferate in the environment pioneered in Ollivier et al. [(2004). Objective properties from subjective quantum states: Environment as a witness. Physical Review Letters, 93, 220401 and (2005). Environment as a witness: Selective proliferation of information and emergence of objectivity in a quantum universe. Physical Review A, 72, 042113]-I show that measurement interactions between two systems only create correlations between a specific set of commuting observables of system 1 and a specific set of commuting observables of system 2. This argument picks out a unique basis in which information flows in the correlations between those sets of commuting observables. I then derive the Born rule for both pure and mixed states and answer some other criticisms of the decision theoretic approach to quantum probability.

    6. The role of supersymmetry phenomenology in particle physics

      SciTech Connect

      Wells, James D.

      2000-12-14

      Supersymmetry phenomenology is an important component of particle physics today. I provide a definition of supersymmetry phenomenology, outline the scope of its activity, and argue its legitimacy. This essay derives from a presentation given at the 2000 SLAC Summer Institute.

    7. State-of-the-Art Particle Physics Detector

      NASA Video Gallery

      The Alpha Magnetic Spectrometer is a state-of-the-art particle physics detector being operated by an international team composed of 60 institutes from 16 countries and organized under United States...

    8. Research program in particle physics. Progress report, January 1, 1992--December 1992

      SciTech Connect

      Sudarshan, E.C.G.; Dicus, D.A.; Ritchie, J.L.; Lang, K.

      1992-07-01

      This report discusses the following topics: Quantum Gravity and Mathematical Physics; Phenomenology; Quantum Mechanics and Quantum Field Theory; Status of BNL Expt. 791; BNL Expt. 791; BNL Expt. 888; and SSC Activities.

    9. Artificial Quantum Solids: Physics, Fabrication and Applications

      DTIC Science & Technology

      2007-11-02

      M. Chandrasekhar, unpublished, 1995; S. Bandyopadhyay, A. E. Miller, and M. Chandrasekhar, in Proc. of SPIE, Photonics West󈨣, San Jose , CA, (PAGE...quantum dot arrays synthesized by a novel electrochemical technique," in Proc. SP1E, Photonics West 󈨣, San Jose /CA, Feb. 1995, vol. 2397, pp. 11...i+-i)iti) + lUi -j^J)* V2V Jh\\+Ap) V2V Jh\\+4p) /l(i--=L=)lU> - /ifi + ^ä^),!- V2V y/hA+4pJ V 2V Jh\\+4J*J In the basis of

    10. On Heisenberg Uncertainty Relationship, Its Extension, and the Quantum Issue of Wave-Particle Duality

      PubMed Central

      Putz, Mihai V.

      2010-01-01

      Within the path integral Feynman formulation of quantum mechanics, the fundamental Heisenberg Uncertainty Relationship (HUR) is analyzed in terms of the quantum fluctuation influence on coordinate and momentum estimations. While introducing specific particle and wave representations, as well as their ratio, in quantifying the wave-to-particle quantum information, the basic HUR is recovered in a close analytical manner for a large range of observable particle-wave Copenhagen duality, although with the dominant wave manifestation, while registering its progressive modification with the factor 1-n2, in terms of magnitude n∈[0,1]. of the quantum fluctuation, for the free quantum evolution around the exact wave-particle equivalence. The practical implications of the present particle-to-wave ratio as well as of the free-evolution quantum picture are discussed for experimental implementation, broken symmetry and the electronic localization function. PMID:21152325

    11. Energetic particle physics with applications in fusion and space plasmas

      SciTech Connect

      Cheng, C.Z.

      1997-05-01

      Energetic particle physics is the study of the effects of energetic particles on collective electromagnetic (EM) instabilities and energetic particle transport in plasmas. Anomalously large energetic particle transport is often caused by low frequency MHD instabilities, which are driven by these energetic particles in the presence of a much denser background of thermal particles. The theory of collective energetic particle phenomena studies complex wave-particle interactions in which particle kinetic physics involving small spatial and fast temporal scales can strongly affect the MHD structure and long-time behavior of plasmas. The difficulty of modeling kinetic-MHD multiscale coupling processes stems from the disparate scales which are traditionally analyzed separately: the macroscale MHD phenomena are studied using the fluid MHD framework, while microscale kinetic phenomena are best described by complicated kinetic theories. The authors have developed a kinetic-MHD model that properly incorporates major particle kinetic effects into the MHD fluid description. For tokamak plasmas a nonvariational kinetic-MHD stability code, the NOVA-K code, has been successfully developed and applied to study problems such as the excitation of fishbone and Toroidal Alfven Eigenmodes (TAE) and the sawtooth stabilization by energetic ions in tokamaks. In space plasmas the authors have employed the kinetic-MHD model to study the energetic particle effects on the ballooning-mirror instability which explains the multisatellite observation of the stability and field-aligned structure of compressional Pc 5 waves in the magnetospheric ring current plasma.

    12. Physics of compaction of fine cohesive particles.

      PubMed

      Castellanos, A; Valverde, J M; Quintanilla, M A S

      2005-02-25

      Fluidized fractal clusters of fine particles display critical-like dynamics at the jamming transition, characterized by a power law relating consolidation stress with volume fraction increment [sigma--(c) proportional, variant(Deltaphi)(beta)]. At a critical stress clusters are disrupted and there is a crossover to a logarithmic law (Deltaphi = nu logsigma--(c)) resembling the phenomenology of soils. We measure lambda identical with- partial differentialDelta(1/phi)/ partial log(sigma--(c) proportional, variant Bo(0.2)(g), where Bo(g) is the ratio of interparticle attractive force (in the fluidlike regime) to particle weight. This law suggests that compaction is ruled by the internal packing structure of the jammed clusters at nearly zero consolidation.

    13. Quarks, Leptons, and Bosons: A Particle Physics Primer.

      ERIC Educational Resources Information Center

      Wagoner, Robert; Goldsmith, Donald

      1983-01-01

      Presented is a non-technical introduction to particle physics. The material is adapted from chapter 3 of "Cosmic Horizons," (by Robert Wagoner and Don Goldsmith), a lay-person's introduction to cosmology. Among the topics considered are elementary particles, forces and motion, and higher level structures. (JN)

    14. Teaching Particle Physics in the Open University's Science Foundation Course.

      ERIC Educational Resources Information Center

      Farmelo, Graham

      1992-01-01

      Discusses four topics presented in the science foundation course of the Open University that exemplify current developments in particle physics, in particular, and that describe important issues about the nature of science, in general. Topics include the omega minus particle, the diversity of quarks, the heavy lepton, and the discovery of the W…

    15. Future particle-physics projects in the United States

      SciTech Connect

      Denisov, D. S.

      2015-08-25

      Basic proposals of experiments aimed at precision measurements of Standard Model parameters and at searches for new particles, including dark-matter particles, are described along with future experimental projects considered by American Physical Society at the meeting in the summer of 2013 and intended for implementation within the next ten to twenty years.

    16. The engineering needed for particle physics.

      PubMed

      Myers, Steve

      2012-08-28

      Today's particle accelerators and detectors are among the most complicated and expensive scientific instruments ever built, and they exploit almost every aspect of today's cutting-edge engineering technologies. In many cases, accelerator needs have been the driving force behind these new technologies, necessity being the mother of invention. This paper gives an overview of some engineering requirements for the construction and operation of present-day accelerators and detectors.

    17. Lagrangian Description for Particle Interpretations of Quantum Mechanics: Entangled Many-Particle Case

      NASA Astrophysics Data System (ADS)

      Sutherland, Roderick I.

      2017-02-01

      A Lagrangian formulation is constructed for particle interpretations of quantum mechanics, a well-known example of such an interpretation being the Bohm model. The advantages of such a description are that the equations for particle motion, field evolution and conservation laws can all be deduced from a single Lagrangian density expression. The formalism presented is Lorentz invariant. This paper follows on from a previous one which was limited to the single-particle case. The present paper treats the more general case of many particles in an entangled state. It is found that describing more than one particle while maintaining a relativistic description requires the specification of final boundary conditions as well as the usual initial ones, with the experimenter's controllable choice of the final conditions thereby exerting a backwards-in-time influence. This retrocausality then allows an important theoretical step forward to be made, namely that it becomes possible to dispense with the usual, many-dimensional description in configuration space and instead revert to a description in space-time using separate, single-particle wavefunctions.

    18. Teaching quantum interpretations: Revisiting the goals and practices of introductory quantum physics courses

      NASA Astrophysics Data System (ADS)

      Baily, Charles; Finkelstein, Noah D.

      2015-12-01

      [This paper is part of the Focused Collection on Upper Division Physics Courses.] Most introductory quantum physics instructors would agree that transitioning students from classical to quantum thinking is an important learning goal, but may disagree on whether or how this can be accomplished. Although (and perhaps because) physicists have long debated the physical interpretation of quantum theory, many instructors choose to avoid emphasizing interpretive themes; or they discuss the views of scientists in their classrooms, but do not adequately attend to student interpretations. In this synthesis and extension of prior work, we demonstrate the following: (i) instructors vary in their approaches to teaching interpretive themes; (ii) different instructional approaches have differential impacts on student thinking; and (iii) when student interpretations go unattended, they often develop their own (sometimes scientifically undesirable) views. We introduce here a new modern physics curriculum that explicitly attends to student interpretations, and provide evidence-based arguments that doing so helps them to develop more consistent interpretations of quantum phenomena, more sophisticated views of uncertainty, and greater interest in quantum physics.

    19. The Oxford Questions on the foundations of quantum physics

      PubMed Central

      Briggs, G. A. D.; Butterfield, J. N.; Zeilinger, A.

      2013-01-01

      The twentieth century saw two fundamental revolutions in physics—relativity and quantum. Daily use of these theories can numb the sense of wonder at their immense empirical success. Does their instrumental effectiveness stand on the rock of secure concepts or the sand of unresolved fundamentals? Does measuring a quantum system probe, or even create, reality or merely change belief? Must relativity and quantum theory just coexist or might we find a new theory which unifies the two? To bring such questions into sharper focus, we convened a conference on Quantum Physics and the Nature of Reality. Some issues remain as controversial as ever, but some are being nudged by theory's secret weapon of experiment. PMID:24062626

    20. Mapping of topological quantum circuits to physical hardware.

      PubMed

      Paler, Alexandru; Devitt, Simon J; Nemoto, Kae; Polian, Ilia

      2014-04-11

      Topological quantum computation is a promising technique to achieve large-scale, error-corrected computation. Quantum hardware is used to create a large, 3-dimensional lattice of entangled qubits while performing computation requires strategic measurement in accordance with a topological circuit specification. The specification is a geometric structure that defines encoded information and fault-tolerant operations. The compilation of a topological circuit is one important aspect of programming a quantum computer, another is the mapping of the topological circuit into the operations performed by the hardware. Each qubit has to be controlled, and measurement results are needed to propagate encoded quantum information from input to output. In this work, we introduce an algorithm for mapping an topological circuit to the operations needed by the physical hardware. We determine the control commands for each qubit in the computer and the relevant measurements that are needed to track information as it moves through the circuit.

    1. Elementary Particle Physics at Baylor (Final Report)

      SciTech Connect

      Dittmann, J.R.

      2012-08-25

      This report summarizes the activities of the Baylor University Experimental High Energy Physics (HEP) group on the Collider Detector at Fermilab (CDF) experiment from August 15, 2005 to May 31, 2012. Led by the Principal Investigator (Dr. Jay R. Dittmann), the Baylor HEP group has actively pursued a variety of cutting-edge measurements from proton-antiproton collisions at the energy frontier.

    2. Research in theoretical and elementary particle physics

      SciTech Connect

      Mitselmakher, G.

      1996-12-01

      In 1995 the University of Florida started a major expansion of the High Energy Experimental Physics group (HEE) with the goal of adding four new faculty level positions to the group in two years. This proposal covers the second year of operation of the new group and gives a projection of the planned research program for the next five years, when the group expects their activities to be broader and well defined. The expansion of the HEE group started in the Fall of 1995 when Guenakh Mitselmakher was hired from Fermilab as a Full Professor. A search was then performed for two junior faculty positions. The first being a Research Scientist/Scholar position which is supported for 9 months by the University on a faculty line at the same level as Assistant Professor but without the teaching duties. The second position is that of an Assistant Professor. The search has been successfully completed and Jacobo Konigsberg from Harvard University has accepted the position of Research Scientist and Andrey Korytov from MIT has accepted the position of Assistant Professor. They will join the group in August 1996. The physics program for the new group is focused on hadron collider physics. G. Mitselmakher has been leading the CMS endcap muon project since 1994. A Korytov is the coordinator of the endcap muon chamber effort for CMS and a member of the CDF collaboration and J. Konigsberg is a member of CDF where he has participated in various physics analyses and has been coordinator of the gas calorimetry group. The group at the U. of Florida has recently been accepted as an official collaborating institution on CDF. They have been assigned the responsibility of determining the collider beam luminosity at CDF and they will also be an active participant in the design and operation of the muon detectors for the intermediate rapidity region. In addition they expect to continue their strong participation in the present and future physics analysis of the CDF data.

    3. From Particle Physics to Astroparticle Physics: Proton Decay and the Rise of Non-accelerator Physics

      NASA Astrophysics Data System (ADS)

      Meyer, Hinrich

      The search for proton decay was motivated by simple questions about the content of the observable universe. Why is matter so stable and why do we not see antimatter of primordial origin? The symmetry of the standard model of particle physics would have required that matter and antimatter annihilated in the early universe. In 1968, Sacharov showed that the matter-antimatter asymmetry could have formed in a state of thermal non-equilibrium of the universe, as given in big bang cosmology, together with the well-confirmed C and CP violations, and proton decay. The latter phenomenon could be only investigated in large none-accelerator experiments. The SU(5) extension of the standard model implied a proton lifetime of about 1029 years. With detectors consisting of 1 000 tons of matter and located deep under the Earth surface, such as the French-German Fréjus iron-calorimeter, in the mid 1980s one expected to detect several proton decays per year. Here, we report on the way leading from accelerator laboratories to underground physics, which paradoxically enough turned out to studying cosmic rays. There has not been any evidence for the instability of protons, and lifetime limits of more than 1034 years have been obtained. However, great progress in particle physics and in the physics of cosmic rays could be achieved with neutrinos.

    4. Time Symmetric Quantum Mechanics and Causal Classical Physics ?

      NASA Astrophysics Data System (ADS)

      Bopp, Fritz W.

      2017-02-01

      A two boundary quantum mechanics without time ordered causal structure is advocated as consistent theory. The apparent causal structure of usual "near future" macroscopic phenomena is attributed to a cosmological asymmetry and to rules governing the transition between microscopic to macroscopic observations. Our interest is a heuristic understanding of the resulting macroscopic physics.

    5. A Quantum Chemistry Concept Inventory for Physical Chemistry Classes

      ERIC Educational Resources Information Center

      Dick-Perez, Marilu; Luxford, Cynthia J.; Windus, Theresa L.; Holme, Thomas

      2016-01-01

      A 14-item, multiple-choice diagnostic assessment tool, the quantum chemistry concept inventory or QCCI, is presented. Items were developed based on published student misconceptions and content coverage and then piloted and used in advanced physical chemistry undergraduate courses. In addition to the instrument itself, data from both a pretest,…

    6. THE CENTENARY OF NIELS BOHR: Niels Bohr and quantum physics

      NASA Astrophysics Data System (ADS)

      Migdal, A. B.

      1985-10-01

      The way of thinking and scientific style of Niels Bohr are discussed in connection with developments of his emotional and spiritual life. Analysis of the papers of Bohr, his predecessors, and his contemporaries reveals that he was a philosopher of physics who had an incomparable influence upon the creation and development of quantum mechanics. His struggle against nuclear weapons is mentioned.

    7. Chapter 1: Physics with Trapped Charged Particles

      NASA Astrophysics Data System (ADS)

      Knoop, Martina; Madsen, Niels; Thompson, Richard C.

      2014-01-01

      Ion traps, which were first introduced in the late 1950s and early 1960s, have established themselves as indispensable tools in many areas of physics, chemistry and technology. This chapter gives a brief survey of the operating principles and development of ion traps, together with a short description of how ions are loaded and detected. This is followed by a brief account of some of the current applications of ion traps.

    8. Theoretical particle physics. Progress report, FY 1992

      SciTech Connect

      Not Available

      1992-09-30

      This report discusses the following topics: heavy quark physics; Chiral Perturbation theory; Skyrmions; quarkonia and nuclear matter; parity violating nuclear matrix elements; how precisely can one determine M{sub U}/M{sub D}; weak scale baryogenesis; constraints of baryogenesis form neutrino masses; majorons, double beta decay, supernova 1987A; rare decays; chiral lattice fermions; Pauli-Villars regulator and the Higgs mass bound; and Higgs and Yukawa interactions.

    9. Equivalence between free quantum particles and those in harmonic potentials and its application to instantaneous changes

      NASA Astrophysics Data System (ADS)

      Steuernagel, Ole

      2014-06-01

      In quantum physics the free particle and the harmonically trapped particle are arguably the most important systems a physicist needs to know about. It is little known that, mathematically, they are one and the same. This knowledge helps us to understand either from the viewpoint of the other. Here we show that all general time-dependent solutions of the free-particle Schrödinger equation can be mapped to solutions of the Schrödinger equation for harmonic potentials, both the trapping oscillator and the inverted "oscillator". This map is fully invertible and therefore induces an isomorphism between both types of system, they are equivalent. A composition of the map and its inverse allows us to map from one harmonic oscillator to another with a different spring constant and different center position. The map is independent of the state of the system, consisting only of a coordinate transformation and multiplication by a form factor, and can be chosen such that the state is identical in both systems at one point in time. This transition point in time can be chosen freely, the wave function of the particle evolving in time in one system before the transition point can therefore be linked up smoothly with the wave function for the other system and its future evolution after the transition point. Such a cut-and-paste procedure allows us to describe the instantaneous changes of the environment a particle finds itself in. Transitions from free to trapped systems, between harmonic traps of different spring constants or center positions, or, from harmonic binding to repulsive harmonic potentials are straightforwardly modelled. This includes some time-dependent harmonic potentials. The mappings introduced here are computationally more efficient than either state-projection or harmonic oscillator propagator techniques conventionally employed when describing instantaneous (non-adiabatic) changes of a quantum particle's environment.

    10. Quantum Dots in a Polymer Composite: A Convenient Particle-in-a-Box Laboratory Experiment

      ERIC Educational Resources Information Center

      Rice, Charles V.; Giffin, Guinevere A.

      2008-01-01

      Semiconductor quantum dots are at the forefront of materials science chemistry with applications in biological imaging and photovoltaic technologies. We have developed a simple laboratory experiment to measure the quantum-dot size from fluorescence spectra. A major roadblock of quantum-dot based exercises is the particle synthesis and handling;…

    11. Black hole bombs and explosions: from astrophysics to particle physics

      NASA Astrophysics Data System (ADS)

      Cardoso, Vitor

      2013-11-01

      Black holes are the elementary particles of gravity, the final state of sufficiently massive stars and of energetic collisions. With a 40-year long history, black hole physics is a fully-blossomed field which promises to embrace several branches of theoretical physics. Here I review the main developments in highly dynamical black holes with an emphasis on high energy black hole collisions and probes of particle physics via superradiance. This write-up, rather than being a collection of well known results, is intended to highlight open issues and the most intriguing results.

    12. Particle and nuclear physics instrumentation and its broad connections

      NASA Astrophysics Data System (ADS)

      Demarteau, M.; Lipton, R.; Nicholson, H.; Shipsey, I.

      2016-10-01

      Subatomic physics shares with other basic sciences the need to innovate, invent, and develop tools, techniques, and technologies to carry out its mission to explore the nature of matter, energy, space, and time. In some cases, entire detectors or technologies developed specifically for particle physics research have been adopted by other fields of research or in commercial applications. In most cases, however, the development of new devices and technologies by particle physics for its own research has added value to other fields of research or to applications beneficial to society by integrating them in the existing technologies. Thus, detector research and development has not only advanced the current state of technology for particle physics, but has often advanced research in other fields of science and has underpinned progress in numerous applications in medicine and national security. At the same time particle physics has profited immensely from developments in industry and applied them to great benefit for the use of particle physics detectors. This symbiotic relationship has seen strong mutual benefits with sometimes unexpected far reach.

    13. Particle and nuclear physics instrumentation and its broad connections

      DOE PAGES

      Demarteau, Marcel; Lipton, Ron; Nicholson, Howard; ...

      2016-12-20

      Subatomic physics shares with other basic sciences the need to innovate, invent, and develop tools, techniques, and technologies to carry out its mission to explore the nature of matter, energy, space, and time. In some cases, entire detectors or technologies developed specifically for particle physics research have been adopted by other fields of research or in commercial applications. In most cases, however, the development of new devices and technologies by particle physics for its own research has added value to other fields of research or to applications beneficial to society by integrating them in the existing technologies. Thus, detector researchmore » and development has not only advanced the current state of technology for particle physics, but has often advanced research in other fields of science and has underpinned progress in numerous applications in medicine and national security. At the same time particle physics has profited immensely from developments in industry and applied them to great benefit for the use of particle physics detectors. Finally, this symbiotic relationship has seen strong mutual benefits with sometimes unexpected far reach.« less

    14. Particle and nuclear physics instrumentation and its broad connections

      SciTech Connect

      Demarteau, Marcel; Lipton, Ron; Nicholson, Howard; Shipsey, Ian

      2016-12-20

      Subatomic physics shares with other basic sciences the need to innovate, invent, and develop tools, techniques, and technologies to carry out its mission to explore the nature of matter, energy, space, and time. In some cases, entire detectors or technologies developed specifically for particle physics research have been adopted by other fields of research or in commercial applications. In most cases, however, the development of new devices and technologies by particle physics for its own research has added value to other fields of research or to applications beneficial to society by integrating them in the existing technologies. Thus, detector research and development has not only advanced the current state of technology for particle physics, but has often advanced research in other fields of science and has underpinned progress in numerous applications in medicine and national security. At the same time particle physics has profited immensely from developments in industry and applied them to great benefit for the use of particle physics detectors. Finally, this symbiotic relationship has seen strong mutual benefits with sometimes unexpected far reach.

    15. Mean particle diameters. From statistical definition to physical understanding.

      PubMed

      Alderliesten, Maarten

      2005-01-01

      Mean particle diameters may be used to describe and to model physical, chemical, or physiological properties of products or materials containing dispersed phases. There are different notation systems for these mean diameters, which may cause much confusion. This equally applies to their nomenclature. This article introduces the Moment-Ratio definition system and evaluates briefly the ISO definition system. The ISO system appears to have serious drawbacks. Mean particle diameters can be estimated from histograms of size distributions by Summation (M-R system) and by Integration (ISO system) over the histogram intervals. Summation tends to be more accurate than Integration and is less sensitive to low values of the lower limit of size distributions. The Summation method equations are straightforward and generally applicable. The mathematical formulas of the Integration method are difficult to apply in daily practice, and their complexity may easily hide the physical background of a mean particle diameter. A coherent nomenclature system for denoting mean particle diameters is recommended. This nomenclature system does not contain any ambiguities and clearly conveys the physical meanings of mean particle diameters. This article deals also with an empirical method to select the proper type of mean diameter to describe a physical, chemical, or physiological property of a product or material containing dispersed phases. After calculation of the mean diameters from experimental data, the relationships between the product property and these mean diameters are investigated statistically. The selection method has been illustrated by two examples. The dataset of each example consists of a set of particle size distributions and the corresponding physical product properties that are influenced by the particle sizes. Hypotheses are formulated to explain the types of selected mean diameters. Sharing results from all over the world of applications of the developed selection method

    16. Universality in uncertainty relations for a quantum particle

      NASA Astrophysics Data System (ADS)

      Kechrimparis, Spiros; Weigert, Stefan

      2016-09-01

      A general theory of preparational uncertainty relations for a quantum particle in one spatial dimension is developed. We derive conditions which determine whether a given smooth function of the particle’s variances and its covariance is bounded from below. Whenever a global minimum exists, an uncertainty relation has been obtained. The squeezed number states of a harmonic oscillator are found to be universal: no other pure or mixed states will saturate any such relation. Geometrically, we identify a convex uncertainty region in the space of second moments which is bounded by the inequality derived by Robertson and Schrödinger. Our approach provides a unified perspective on existing uncertainty relations for a single continuous variable, and it leads to new inequalities for second moments which can be checked experimentally.

    17. Non-extensive quantum statistics with particle-hole symmetry

      NASA Astrophysics Data System (ADS)

      Biró, T. S.; Shen, K. M.; Zhang, B. W.

      2015-06-01

      Based on Tsallis entropy (1988) and the corresponding deformed exponential function, generalized distribution functions for bosons and fermions have been used since a while Teweldeberhan et al. (2003) and Silva et al. (2010). However, aiming at a non-extensive quantum statistics further requirements arise from the symmetric handling of particles and holes (excitations above and below the Fermi level). Naive replacements of the exponential function or "cut and paste" solutions fail to satisfy this symmetry and to be smooth at the Fermi level at the same time. We solve this problem by a general ansatz dividing the deformed exponential to odd and even terms and demonstrate that how earlier suggestions, like the κ- and q-exponential behave in this respect.

    18. A semiclassical hybrid approach to many particle quantum dynamics

      NASA Astrophysics Data System (ADS)

      Grossmann, Frank

      2006-07-01

      We analytically derive a correlated approach for a mixed semiclassical many particle dynamics, treating a fraction of the degrees of freedom by the multitrajectory semiclassical initial value method of Herman and Kluk [Chem. Phys. 91, 27 (1984)] while approximately treating the dynamics of the remaining degrees of freedom with fixed initial phase space variables, analogously to the thawed Gaussian wave packet dynamics of Heller [J. Chem. Phys. 62, 1544 (1975)]. A first application of this hybrid approach to the well studied Secrest-Johnson [J. Chem. Phys. 45, 4556 (1966)] model of atom-diatomic collisions is promising. Results close to the quantum ones for correlation functions as well as scattering probabilities could be gained with considerably reduced numerical effort as compared to the full semiclassical Herman-Kluk approach. Furthermore, the harmonic nature of the different degrees of freedom can be determined a posteriori by comparing results with and without the additional approximation.

    19. A semiclassical hybrid approach to many particle quantum dynamics.

      PubMed

      Grossmann, Frank

      2006-07-07

      We analytically derive a correlated approach for a mixed semiclassical many particle dynamics, treating a fraction of the degrees of freedom by the multitrajectory semiclassical initial value method of Herman and Kluk [Chem. Phys. 91, 27 (1984)] while approximately treating the dynamics of the remaining degrees of freedom with fixed initial phase space variables, analogously to the thawed Gaussian wave packet dynamics of Heller [J. Chem. Phys. 62, 1544 (1975)]. A first application of this hybrid approach to the well studied Secrest-Johnson [J. Chem. Phys. 45, 4556 (1966)] model of atom-diatomic collisions is promising. Results close to the quantum ones for correlation functions as well as scattering probabilities could be gained with considerably reduced numerical effort as compared to the full semiclassical Herman-Kluk approach. Furthermore, the harmonic nature of the different degrees of freedom can be determined a posteriori by comparing results with and without the additional approximation.

    20. Particle physics and condensed matter: the saga continues

      NASA Astrophysics Data System (ADS)

      Wilczek, Frank

      2016-12-01

      Ideas from quantum field theory and topology have proved remarkably fertile in suggesting new phenomena in the quantum physics of condensed matter. Here I will supply some broad, unifying context, both conceptual and historical, for the abundance of results reported at the Nobel Symposium on ‘New Forms of Matter, Topological Insulators and Superconductors’. Since they distill some most basic ideas in their simplest forms, these concluding remarks might also serve, for non-specialists, as an introduction. Invited presentation of concluding remarks at Nobel Symposium 156 on New Forms of Matter, Topological Insulators and Superconductors, 13-15 June 2014, Högberga Gård, Stockholm.

    1. Santa Cruz Institute for Particle Physics (SCIPP)

      SciTech Connect

      Burchat, P.; Dorfan, D.; Litke, A.; Heusch, C.; Sadrozinski, H.; Schalk, T.; Seiden, A.

      1992-11-01

      Work for the coming year is a logical continuation of the efforts of the past year. Some special highlights of this past year which are discusses in more detail in this report are: (1) The move onto beamline and start of ZEUS data taking. (2) The completion of the SDC technical proposal including a detailed long-term plan for construction. (3) Continuing publication of very detailed physics results from ALEPH concerning {tau} and b physics, and a precision measurement of electroweak and QCD parameters. (4) Completion of very successful data taking for E-791 at Fermilab, with nearly twice as many events recorded as initially proposed. (5) First measurement of beam polarization at the SLC. These efforts have led to about 15 physics publications this past year centered mainly on topics related to QCD, couplings of flavors to the Z{degrees}, and heavy flavor decays. Taken as a whole, the results in jets from LEP, the ratio of hadronic to leptonic decays of the {tau} the leptonic branching fraction of the J/{psi}, and the charmonium mass spectrum provide a very consistent set of values of {alpha}{sub s} at a variety of scales. In particular, they show the running of {alpha}{sub s} by a factor of about three from m{sub r} to m{sub z}. Results from LEP also provide evidence of the triple gluon vertex. Similarly, the measurement of the b{bar b} fraction of Z{degrees} decays, from the MARK II as well as LEP, provide increasingly better measurements of the Z{degree} coupling to b quarks. Combined with earlier precision measurements of the Z{degrees} mass, width, and leptonic branching fractions, the Z{degrees} decays continue to provide a very precise verification of the Standard Model.

    2. Santa Cruz Institute for Particle Physics (SCIPP)

      SciTech Connect

      Burchat, P.; Dorfan, D.; Litke, A.; Heusch, C.; Sadrozinski, H.; Schalk, T.; Seiden, A.

      1992-01-01

      Work for the coming year is a logical continuation of the efforts of the past year. Some special highlights of this past year which are discusses in more detail in this report are: (1) The move onto beamline and start of ZEUS data taking. (2) The completion of the SDC technical proposal including a detailed long-term plan for construction. (3) Continuing publication of very detailed physics results from ALEPH concerning [tau] and b physics, and a precision measurement of electroweak and QCD parameters. (4) Completion of very successful data taking for E-791 at Fermilab, with nearly twice as many events recorded as initially proposed. (5) First measurement of beam polarization at the SLC. These efforts have led to about 15 physics publications this past year centered mainly on topics related to QCD, couplings of flavors to the Z[degrees], and heavy flavor decays. Taken as a whole, the results in jets from LEP, the ratio of hadronic to leptonic decays of the [tau] the leptonic branching fraction of the J/[psi], and the charmonium mass spectrum provide a very consistent set of values of [alpha][sub s] at a variety of scales. In particular, they show the running of [alpha][sub s] by a factor of about three from m[sub r] to m[sub z]. Results from LEP also provide evidence of the triple gluon vertex. Similarly, the measurement of the b[bar b] fraction of Z[degrees] decays, from the MARK II as well as LEP, provide increasingly better measurements of the Z[degree] coupling to b quarks. Combined with earlier precision measurements of the Z[degrees] mass, width, and leptonic branching fractions, the Z[degrees] decays continue to provide a very precise verification of the Standard Model.

    3. Path-integral approach to 't Hooft's derivation of quantum physics from classical physics

      SciTech Connect

      Blasone, Massimo; Jizba, Petr; Kleinert, Hagen

      2005-05-15

      We present a path-integral formulation of 't Hooft's derivation of quantum physics from classical physics. The crucial ingredient of this formulation is Gozzi et al.'s supersymmetric path integral of classical mechanics. We quantize explicitly two simple classical systems: the planar mathematical pendulum and the Roessler dynamical system.

    4. Understanding Probabilistic Interpretations of Physical Systems: A Prerequisite to Learning Quantum Physics.

      ERIC Educational Resources Information Center

      Bao, Lei; Redish, Edward F.

      2002-01-01

      Explains the critical role of probability in making sense of quantum physics and addresses the difficulties science and engineering undergraduates experience in helping students build a model of how to think about probability in physical systems. (Contains 17 references.) (Author/YDS)

    5. Quantum physics inspired optical effects in evanescently coupled waveguides

      NASA Astrophysics Data System (ADS)

      Thompson, Clinton Edward

      The tight-binding model that has been used for many years in condensed matter physics, due to its analytic and numerical tractability, has recently been used to describe light propagating through an array of evanescently coupled waveguides. This dissertation presents analytic and numerical simulation results of light propagating in a waveguide array. The first result presented is that photonic transport can be achieved in an array where the propagation constant is linearly increasing across the array. For an input at the center waveguide, the breathing modes of the system are observed, while for a phase displaced, asymmetric input, phase-controlled photonic transport is predicted. For an array with a waveguide-dependent, parity-symmetric coupling constant, the wave packet dynamics are predicted to be tunable. In addition to modifying the propagation constant, the coupling between waveguides can also be modified, and the quantum correlations are sensitive to the form of the tunneling function. In addition to modifying the waveguide array parameters in a structured manner, they can be randomized as to mimic the insertion of impurities during the fabrication process. When the refractive indices are randomized and real, the amount of light that localizes to the initial waveguide is found to be dependent on the initial waveguide when the waveguide coupling is non-uniform. In addition, when the variance of the refractive indices is small, light localizes in the initial waveguide as well as the parity-symmetric waveguide. In addition to real valued disorder, complex valued disorder can be introduced into the array through the imaginary component of the refractive index. It is shown that the two-particle correlation function is qualitatively similar to the case when the waveguide coupling is real and random, as both cases preserve the symmetry of the eigenvalues. Lastly, different input fields have been used to investigate the quantum statistical aspects of Anderson

    6. A derivation of quantum theory from physical requirements

      NASA Astrophysics Data System (ADS)

      Masanes, Lluís; Müller, Markus P.

      2011-06-01

      Quantum theory (QT) is usually formulated in terms of abstract mathematical postulates involving Hilbert spaces, state vectors and unitary operators. In this paper, we show that the full formalism of QT can instead be derived from five simple physical requirements, based on elementary assumptions regarding preparations, transformations and measurements. This is very similar to the usual formulation of special relativity, where two simple physical requirements—the principles of relativity and light speed invariance—are used to derive the mathematical structure of Minkowski space-time. Our derivation provides insights into the physical origin of the structure of quantum state spaces (including a group-theoretic explanation of the Bloch ball and its three dimensionality) and suggests several natural possibilities to construct consistent modifications of QT.

    7. Elementary particle physics at the University of Florida. Annual progress report

      SciTech Connect

      Not Available

      1991-12-01

      This report discusses research in the following areas: theoretical elementary particle physics; experimental elementary particle physics; axion project; SSC detector development; and computer acquisition. (LSP).

    8. Quantum field theory results for neutrino oscillations and new physics

      SciTech Connect

      Delepine, D.; Gonzalez Macias, Vannia; Khalil, Shaaban; Lopez Castro, G.

      2009-05-01

      The CP asymmetry in neutrino oscillations, assuming new physics at production and/or detection processes, is analyzed. We compute this CP asymmetry using the standard quantum field theory within a general new physics scenario that may generate new sources of CP and flavor violation. Well-known results for the CP asymmetry are reproduced in the case of V-A operators, and additional contributions from new physics operators are derived. We apply this formalism to SUSY extensions of the standard model where the contributions from new operators could produce a CP asymmetry observable in the next generation of neutrino experiments.

    9. Large numbers hypothesis. IV - The cosmological constant and quantum physics

      NASA Technical Reports Server (NTRS)

      Adams, P. J.

      1983-01-01

      In standard physics quantum field theory is based on a flat vacuum space-time. This quantum field theory predicts a nonzero cosmological constant. Hence the gravitational field equations do not admit a flat vacuum space-time. This dilemma is resolved using the units covariant gravitational field equations. This paper shows that the field equations admit a flat vacuum space-time with nonzero cosmological constant if and only if the canonical LNH is valid. This allows an interpretation of the LNH phenomena in terms of a time-dependent vacuum state. If this is correct then the cosmological constant must be positive.

    10. Photon physics: from wave mechanics to quantum electrodynamics

      NASA Astrophysics Data System (ADS)

      Keller, Ole

      2009-05-01

      When rewritten in an appropriate manner, the microscopic Maxwell-Lorentz equations appear as a wave-mechanical theory for photons, and their quantum physical interaction with matter. A natural extension leads from photon wave mechanics to quantum electrodynamics (QED). In its modern formulation photon wave mechanics has given us valuable new insight in subjects such as spatial photon localization, near-field photon dynamics, transverse photon mass, photon eikonal theory, photon tunneling, and rim-zone electrodynamics. The present review is based on my plenary lecture at the SPIE-Europe 2009 Optics and Optoelectronics International Symposium in Prague.

    11. Physical theories, eternal inflation, and the quantum universe

      NASA Astrophysics Data System (ADS)

      Nomura, Yasunori

      2011-11-01

      Infinities in eternal inflation have long been plaguing cosmology, making any predictions highly sensitive to how they are regulated. The problem exists already at the level of semi-classical general relativity, and has a priori nothing to do with quantum gravity. On the other hand, we know that certain problems in semi-classical gravity, for example physics of black holes and their evaporation, have led to understanding of surprising, quantum natures of spacetime and gravity, such as the holographic principle and horizon complementarity. In this paper, we present a framework in which well-defined predictions are obtained in an eternally inflating multiverse, based on the principles of quantum mechanics. We propose that the entire multiverse is described purely from the viewpoint of a single "observer," who describes the world as a quantum state defined on his/her past light cones bounded by the (stretched) apparent horizons. We find that quantum mechanics plays an essential role in regulating infinities. The framework is "gauge invariant," i.e. predictions do not depend on how spacetime is parametrized, as it should be in a theory of quantum gravity. Our framework provides a fully unified treatment of quantum measurement processes and the multiverse. We conclude that the eternally inflating multiverse and many worlds in quantum mechanics are the same. Other important implications include: global spacetime can be viewed as a derived concept; the multiverse is a transient phenomenon during the world relaxing into a supersymmetric Minkowski state. We also present a model of "initial conditions" for the multiverse. By extrapolating our framework to the extreme, we arrive at a picture that the entire multiverse is a fluctuation in the stationary, fractal "mega-multiverse," in which an infinite sequence of multiverse productions occurs. The framework discussed here does not suffer from problems/paradoxes plaguing other measures proposed earlier, such as the youngness

    12. Finite-particle-number approach to physics

      SciTech Connect

      Noyes, H.P.

      1982-10-01

      Starting from a discrete, self-generating and self-organizing, recursive model and self-consistent interpretive rules we construct: the scale constants of physics (3,10,137,1.7x10/sup 38/); 3+1 Minkowski space with a discrete metric and the algebraic bound ..delta.. is an element of ..delta.. tau is greater than or equal to 1; the Einstein-deBroglie relation; algebraic double slit interference; a single-time momentum-space scattering theory connected to laboratory experience; an approximation to wave functions; local phase severance and hence both distant correlations and separability; baryon number, lepton number, charge and helicity; m/sub p//m/sub e/; a cosmology not in disagreement with current observations.

    13. Particle-physics constraints on multifractal spacetimes

      NASA Astrophysics Data System (ADS)

      Calcagni, Gianluca; Nardelli, Giuseppe; Rodríguez-Fernández, David

      2016-01-01

      We study electroweak interactions in the multiscale theory with q -derivatives, a framework where spacetime has the typical features of a multifractal. In the simplest case with only one characteristic time, length, and energy scale t* , ℓ* , and E* , we consider (i) the muon decay rate and (ii) the Lamb shift in the hydrogen atom, and constrain the corrections to the ordinary results. We obtain the independent absolute upper bounds (i) t*<1 0-13 s and (ii) E*>35 MeV . Under some mild theoretical assumptions, the Lamb shift alone yields the even tighter ranges t*<1 0-27 s , ℓ*<1 0-19 m , and E*>450 GeV . To date, these are the first robust constraints on the scales at which the multifractal features of the geometry can become important in a physical process.

    14. Spinorial space-time and the origin of Quantum Mechanics. The dynamical role of the physical vacuum

      NASA Astrophysics Data System (ADS)

      Gonzalez-Mestres, Luis

      2016-11-01

      Is Quantum Mechanics really and ultimate principle of Physics described by a set of intrinsic exact laws? Are standard particles the ultimate constituents of matter? The two questions appear to be closely related, as a preonic structure of the physical vacuum would have an influence on the properties of quantum particles. Although the first preon models were just « quark-like » and assumed preons to be direct constituents of the conventional « elementary » particles, we suggested in 1995 that preons could instead be constituents of the physical vacuum (the superbradyon hypothesis). Standard particles would then be excitations of the preonic vacuum and have substantially different properties from those of preons themselves (critical speed…). The standard laws of Particle Physics would be approximate expressions generated from basic preon dynamics. In parallel, the mathematical properties of space-time structures such as the spinoral space-time (SST) we introduced in 1996-97 can have strong implications for Quantum Mechanics and even be its real origin. We complete here our recent discussion of the subject by pointing out that: i) Quantum Mechanics corresponds to a natural set of properties of vacuum excitations in the presence of a SST geometry ; ii) the recently observed entanglement at long distances would be a logical property if preons are superluminal (superbradyons), so that superluminal signals and correlations can propagate in vacuum ; iii) in a specific description, the function of space-time associated to the extended internal structure of a spin-1/2 particle at very small distances may be incompatible with a continuous motion at space and time scales where the internal structure of vacuum can be felt. In the dynamics associated to iii), and using the SST approach to space-time, a contradiction can appear between macroscopic and microscopic space-times due to an overlap in the time variable directly related to the fact that a spinorial function takes

    15. Edge physics of the quantum spin Hall insulator from a quantum dot excited by optical absorption.

      PubMed

      Vasseur, Romain; Moore, Joel E

      2014-04-11

      The gapless edge modes of the quantum spin Hall insulator form a helical liquid in which the direction of motion along the edge is determined by the spin orientation of the electrons. In order to probe the Luttinger liquid physics of these edge states and their interaction with a magnetic (Kondo) impurity, we consider a setup where the helical liquid is tunnel coupled to a semiconductor quantum dot that is excited by optical absorption, thereby inducing an effective quantum quench of the tunneling. At low energy, the absorption spectrum is dominated by a power-law singularity. The corresponding exponent is directly related to the interaction strength (Luttinger parameter) and can be computed exactly using boundary conformal field theory thanks to the unique nature of the quantum spin Hall edge.

    16. Particle physics for primary schools—enthusing future physicists

      NASA Astrophysics Data System (ADS)

      Pavlidou, M.; Lazzeroni, C.

      2016-09-01

      In recent years, the realisation that children make decisions and choices about subjects they like in primary school, became widely understood. For this reason academic establishments focus some of their public engagement activities towards the younger ages. Taking advantage of Professor Lazzeroni’s long-standing experience in particle physics research, during the last academic year we designed and trialled a particle physics workshop for primary schools. The workshop allows young children (ages 8-11) to learn the world of fundamental particles, use creative design to make particle models. The workshop has already been trialled in many primary schools, receiving very positive evaluation. The initial resources were reviewed and improved, based on the feedback received from school teachers and communicators.

    17. Young's double-slit interference for quantum particles

      NASA Astrophysics Data System (ADS)

      Ozer, Zehra Nur; Chaluvadi, Hari; Ulu, Melike; Dogan, Mevlut; Aktas, Bekir; Madison, Don

      2013-04-01

      For the last 50 years, there has been considerable interest in the possibility of observing the equivalence of a Young's double-slit wave interference at the quantum level for diatomic molecules. For electron-impact ionization of diatomic molecules, indirect evidence for this type of interference has been found by changing the energy (wavelength) of the ejected electron while keeping the incident projectile scattering angle fixed. The present work represents an experimental and theoretical collaboration to better understand the physics of this type of interference. In addition to examining the effect of changing the ejected electron energy for a fixed scattered projectile angle, we have also examined the effect of keeping the ejected electron energy fixed while varying the projectile scattering angle. Model calculations are performed for three different types of possible two-center interference effects, and it is found that the most important one is diffraction of the projectile off two scattering centers.

    18. Physical and chemical characterization of tire-related particles: comparison of particles generated using different methodologies.

      PubMed

      Kreider, Marisa L; Panko, Julie M; McAtee, Britt L; Sweet, Leonard I; Finley, Brent L

      2010-01-01

      The purpose of this study was to characterize the physical and chemical properties of particles generated from the interaction of tires and road surfaces. Morphology, size distribution, and chemical composition were compared between particles generated using different methods, including on-road collection, laboratory generation under simulated driving conditions, and cryogenic breaking of tread rubber. Both on-road collected and laboratory generated particles exhibited the elongated shape typical of tire wear particles, whereas tread particles were more angular. Despite similar morphology for the on-road collected and the laboratory generated particles, the former were smaller on average. It is not clear at this stage if the difference is significant to the physical and chemical behavior of the particles. The chemical composition of the particles differed, with on-road generated particles containing chemical contributions from sources other than tires, such as pavement or particulates generated from other traffic-related sources. Understanding the differences between these particles is essential in apportioning contaminant contributions to the environment between tires, roadways, and other sources, and evaluating the representativeness of toxicity studies using different types of particulate generated.

    19. Beyond quantum probability: another formalism shared by quantum physics and psychology.

      PubMed

      Dzhafarov, Ehtibar N; Kujala, Janne V

      2013-06-01

      There is another meeting place for quantum physics and psychology, both within and outside of cognitive modeling. In physics it is known as the issue of classical (probabilistic) determinism, and in psychology it is known as the issue of selective influences. The formalisms independently developed in the two areas for dealing with these issues turn out to be identical, opening ways for mutually beneficial interactions.

    20. Beyond Standard Model Physics: At the Frontiers of Cosmology and Particle Physics

      NASA Astrophysics Data System (ADS)

      Lopez-Suarez, Alejandro O.

      I begin to write this thesis at a time of great excitement in the field of cosmology and particle physics. The aim of this thesis is to study and search for beyond the standard model (BSM) physics in the cosmological and high energy particle fields. There are two main questions, which this thesis aims to address: 1) what can we learn about the inflationary epoch utilizing the pioneer gravitational wave detector Adv. LIGO?, and 2) what are the dark matter particle properties and interactions with the standard model particles?. This thesis will focus on advances in answering both questions.

    1. Particle Physics: Will Britain Kill its Own Creation?

      NASA Astrophysics Data System (ADS)

      Salam, Abdus

      There is no question but that particle physics is a British invention. Of the four building blocks of matter that nuclear physics and cosmology deal with — electrons, neutrons, protons and neutrinos — two were discovered at Cambridge and one at Manchester. This was before the Second World War, but after the war the tradition continued. Cecil Powell's group at Bristol found the pion, which had been predicted by Hideki Yukawa; and the first of the so-called "strange" particles was discovered by Patrick Blackett, George Rochester and Clifford Butler working at Manchester…

    2. Nuclear and particle physics, astrophysics and cosmology (NPAC) capability review

      SciTech Connect

      Redondo, Antonio

      2010-01-01

      The present document represents a summary self-assessment of the status of the Nuclear and Particle Physics, Astrophysics and Cosmology (NPAC) capability across Los Alamos National Laboratory (LANL). For the purpose of this review, we have divided the capability into four theme areas: Nuclear Physics, Particle Physics, Astrophysics and Cosmology, and Applied Physics. For each theme area we have given a general but brief description of the activities under the area, a list of the Laboratory divisions involved in the work, connections to the goals and mission of the Laboratory, a brief description of progress over the last three years, our opinion of the overall status of the theme area, and challenges and issues.

    3. The Pendulum as a Vehicle for Transitioning from Classical to Quantum Physics: History, Quantum Concepts, and Educational Challenges

      ERIC Educational Resources Information Center

      Barnes, Marianne B.; Garner, James; Reid, David

      2004-01-01

      In this article we use the pendulum as the vehicle for discussing the transition from classical to quantum physics. Since student knowledge of the classical pendulum can be generalized to all harmonic oscillators, we propose that a quantum analysis of the pendulum can lead students into the unanticipated consequences of quantum phenomena at the…

    4. TEACHING PHYSICS: The quantum understanding of pre-university physics students

      NASA Astrophysics Data System (ADS)

      Ireson, Gren

      2000-01-01

      Students in England and Wales wishing to read for a physics-based degree will, in all but the more exceptional situations, be required to follow the two-year GCE Advanced-level physics course. This course includes, in its mandatory core, material that addresses the topic of `quantum phenomena'. Over the years journals such as this have published teaching strategies, for example Lawrence (1996), but few studies addressing what students understand of quantum phenomena can be found. This paper aims to address just this problem.

    5. Quantum information processing, operational quantum logic, convexity, and the foundations of physics

      NASA Astrophysics Data System (ADS)

      Barnum, Howard

      Quantum information science is a source of task-related axioms whose consequences can be explored in general settings encompassing quantum mechanics, classical theory, and more. Quantum states are compendia of probabilities for the outcomes of possible operations we may perform on a system: "operational states." I discuss general frameworks for "operational theories" (sets of possible operational states of a system), in which convexity plays key role. The main technical content of the paper is in a theorem that any such theory naturally gives rise to a "weak effect algebra" when outcomes having the same probability in all states are identified and in the introduction of a notion of "operation algebra" that also takes account of sequential and conditional operations. Such frameworks are appropriate for investigating what things look like from an "inside view," i.e., for describing perspectival information that one subsystem of the world can have about another. Understanding how such views can combine, and whether an overall "geometric" picture ("outside view") coordinating them all can be had, even if this picture is very different in structure from the perspectives within it, is the key to whether we may be able to achieve a unified, "objective" physical view in which quantum mechanics is the appropriate description for certain perspectives, or whether quantum mechanics is truly telling us we must go beyond this "geometric" conception of physics.

    6. Research accomplishments and future goals in particle physics

      SciTech Connect

      Not Available

      1990-11-30

      This document presents our proposal to continue the activities of Boston University researchers in high energy physics research. We have a broad program of participation in both non-accelerator and accelerator-based efforts. High energy research at Boston University has a special focus on the physics program of the Superconducting Supercollider. We are active in research and development for detector subsystems, in the design of experiments, and in study of the phenomenology of the very high energy interactions to be observed at the SSC. The particular areas discussed in this paper are: colliding beams physics; accelerator design physics; MACRO project; proton decay project; theoretical particle physics; muon G-2 project; fast liquid scintillators; SSCINTCAL project; TRD project; massively parallel processing for the SSC; and physics analysis and vertex detector upgrade at L3.

    7. Using optical clock to probe quantum many-body physics

      NASA Astrophysics Data System (ADS)

      Ye, Jun

      2016-05-01

      The progress of optical lattice clock has benefited greatly from the understanding of atomic interactions. At the same time, the precision of clock spectroscopy has been applied to explore many-body spin interactions including SU(N) symmetry. Our recent work on this combined front of quantum metrology and many-body physics includes the probe of spin-orbital physics in the lattice clock and the investigation of a Fermi degenerate gas of 105 87Sr atoms in a three-dimensional magic-wavelength optical lattice.

    8. Multi-party quantum summation without a trusted third party based on single particles

      NASA Astrophysics Data System (ADS)

      Zhang, Cai; Situ, Haozhen; Huang, Qiong; Yang, Pingle

      We propose multi-party quantum summation protocols based on single particles, in which participants are allowed to compute the summation of their inputs without the help of a trusted third party and preserve the privacy of their inputs. Only one participant who generates the source particles needs to perform unitary operations and only single particles are needed in the beginning of the protocols.

    9. Magnetic particle motions within living cells. Physical theory and techniques.

      PubMed Central

      Valberg, P A; Butler, J P

      1987-01-01

      Body tissues are not ferromagnetic, but ferromagnetic particles can be present as contaminants or as probes in the lungs and in other organs. The magnetic domains of these particles can be aligned by momentary application of an external magnetic field; the magnitude and time course of the resultant remanent field depend on the quantity of magnetic material and the degree of particle motion. The interpretation of magnetometric data requires an understanding of particle magnetization, agglomeration, random motion, and both rotation and translation in response to magnetic fields. We present physical principles relevant to magnetometry and suggest models for intracellular particle motion driven by thermal, elastic, or cellular forces. The design principles of instrumentation for magnetizing intracellular particles and for detecting weak remanent magnetic fields are described. Such magnetic measurements can be used for noninvasive studies of particle clearance from the body or of particle motion within body tissues and cells. Assumptions inherent to this experimental approach and possible sources of artifact are considered and evaluated. PMID:3676435

    10. Research in elementary particle physics. [Ohio State Univ. , Columbus

      SciTech Connect

      Not Available

      1992-01-01

      Experimental and theoretical work on high energy physics is reviewed. Included are preparations to study high-energy electron-proton interactions at HERA, light-cone QCD, decays of charm and beauty particles, neutrino oscillation, electron-positron interactions at CLEO II, detector development, and astrophysics and cosmology.

    11. My 50 years of research in particle physics.

      PubMed

      Sugawara, Hirotaka

      2010-01-01

      Some of my work of the last 50 years in the field of theoretical particle physics is described with particular emphasis on the motivation, the process of investigation, relationship to the work of others, and its impact. My judgment is unavoidably subjective, although I do present the comments of other researchers as much as possible.

    12. Nobel physics prize to Charpak for inventing particle detectors

      SciTech Connect

      Schwarzschild, B.

      1993-01-01

      This article describes the work of Georges Charpak of France leading to his receipt of the 1992 Nobel Prize in Physics. The Nobel Prize was awarded to Charpak [open quotes]for his invention and development of particle detectors, in particular the multiwire proportional chamber.[close quotes] Historical aspects of Charpak's life and research are given.

    13. My 50 years of research in particle physics

      PubMed Central

      Sugawara, Hirotaka

      2010-01-01

      Some of my work of the last 50 years in the field of theoretical particle physics is described with particular emphasis on the motivation, the process of investigation, relationship to the work of others, and its impact. My judgment is unavoidably subjective, although I do present the comments of other researchers as much as possible. PMID:20431257

    14. Quantum work statistics of charged Dirac particles in time-dependent fields

      DOE PAGES

      Deffner, Sebastian; Saxena, Avadh

      2015-09-28

      The quantum Jarzynski equality is an important theorem of modern quantum thermodynamics. We show that the Jarzynski equality readily generalizes to relativistic quantum mechanics described by the Dirac equation. After establishing the conceptual framework we solve a pedagogical, yet experimentally relevant, system analytically. As a main result we obtain the exact quantum work distributions for charged particles traveling through a time-dependent vector potential evolving under Schrödinger as well as under Dirac dynamics, and for which the Jarzynski equality is verified. Thus, special emphasis is put on the conceptual and technical subtleties arising from relativistic quantum mechanics.

    15. Quantum work statistics of charged Dirac particles in time-dependent fields

      NASA Astrophysics Data System (ADS)

      Deffner, Sebastian; Saxena, Avadh

      2015-09-01

      The quantum Jarzynski equality is an important theorem of modern quantum thermodynamics. We show that the Jarzynski equality readily generalizes to relativistic quantum mechanics described by the Dirac equation. After establishing the conceptual framework we solve a pedagogical, yet experimentally relevant, system analytically. As a main result we obtain the exact quantum work distributions for charged particles traveling through a time-dependent vector potential evolving under Schrödinger as well as under Dirac dynamics, and for which the Jarzynski equality is verified. Special emphasis is put on the conceptual and technical subtleties arising from relativistic quantum mechanics.

    16. Particle acceleration, transport and turbulence in cosmic and heliospheric physics

      NASA Technical Reports Server (NTRS)

      Matthaeus, W.

      1992-01-01

      In this progress report, the long term goals, recent scientific progress, and organizational activities are described. The scientific focus of this annual report is in three areas: first, the physics of particle acceleration and transport, including heliospheric modulation and transport, shock acceleration and galactic propagation and reacceleration of cosmic rays; second, the development of theories of the interaction of turbulence and large scale plasma and magnetic field structures, as in winds and shocks; third, the elucidation of the nature of magnetohydrodynamic turbulence processes and the role such turbulence processes might play in heliospheric, galactic, cosmic ray physics, and other space physics applications.

    17. Current experiments in elementary particle physics. Revision 1-85

      SciTech Connect

      Wohl, C.G.; Armstrong, F.E.; Rittenberg, A.; Trippe, T.G.; Yost, G.P.; Oyanagi, Y.; Dodder, D.C.; Grudtsin, S.N.; Ryabov, Yu.G.; Frosch, R.

      1985-01-01

      This report contains summaries of 551 approved experiments in elementary particle physics (experiments that finished taking data before 1 January 1980 are excluded). Included are experiments at Brookhaven, CERN, CESR, DESY, Fermilab, Moscow Institute of Theoretical and Experimental Physics, Tokyo Institute of Nuclear Studies, KEK, LAMPF, Leningrad Nuclear Physics Institute, Saclay, Serpukhov, SIN, SLAC, and TRIUMF, and also experiments on proton decay. Properties of the fixed-target beams at most of the laboratories are summarized. Instructions are given for searching online the computer database (maintained under the SLAC/SPIRES system) that contains the summaries.

    18. Quantum probability and cognitive modeling: some cautions and a promising direction in modeling physics learning.

      PubMed

      Franceschetti, Donald R; Gire, Elizabeth

      2013-06-01

      Quantum probability theory offers a viable alternative to classical probability, although there are some ambiguities inherent in transferring the quantum formalism to a less determined realm. A number of physicists are now looking at the applicability of quantum ideas to the assessment of physics learning, an area particularly suited to quantum probability ideas.

    19. Particle radiosurgery: a new frontier of physics in medicine.

      PubMed

      Bert, Christoph; Durante, Marco

      2014-07-01

      Radiosurgery was introduced over half a century ago for treatment of intracranial lesions. In more recent years, stereotactic radiotherapy has rapidly advanced and is now commonly used for treatments of both cranial and extracranial lesions with high doses delivered in a few, down to a single fraction. The results of a workshop on Particle radiosurgery: A new frontier of physics in medicine held at Obergurgl, Austria during August 25-29 2013 are summarized in this issue with an overview presented in this paper. The focus was laid on particle radiosurgery but the content also includes current practice in x-ray radiosurgery and the overarching research in radiobiology and motion management for extracranial lesions. The results and discussions showed that especially research in radiobiology of high-dose charged-particles and motion management are necessary for the success of particle radiosurgery.

    20. Integrating particle physical geometry into composting degradation kinetics.

      PubMed

      Wang, Yongjiang; Ai, Ping

      2016-01-01

      The study was carried out to integrate physical geometry of compost particle with degradation kinetics to model biological reactions, which revealing additional dynamic approaches. A sphere and its circumscribing cube were used to represent compost particles. An inner sphere, representing anaerobic zone, was introduced to describe variations of substrate volume without sufficient oxygen supply. Degradation of soluble substrates and hydrolysis of insoluble substrates were associated with the particle geometry. Transportation of soluble substrates produced from hydrolysis was expressed using Fick's law. Through the integration of degradation kinetics with geometry models, degradation models could describe varying volume of composting materials involving aerobic or anaerobic digestion and transportation of soluble substrates in a unit compost particle.

    1. Particle Physics in High School: A Diagnose Study.

      PubMed

      Tuzón, Paula; Solbes, Jordi

      2016-01-01

      The science learning process improves when the contents are connected to students' lives. Particle physics has had a great impact in our society in the last years and has changed the theoretical picture about matter fundamental dynamics. Thus, we think that academic contents about matter components and interactions should be updated. With this study we aim to characterize the level of knowledge of high school students about this topic. We built a test with questions about classical atomic models, particle physics, recent discoveries, social implications and students opinions about it. Contrary to our first suspicion, students' answers show a high variability. They have new physics ideas and show a great interest towards modern concepts. We suggest including an updated view of this topic as part of the curriculum.

    2. Particle Physics in High School: A Diagnose Study

      PubMed Central

      Solbes, Jordi

      2016-01-01

      The science learning process improves when the contents are connected to students’ lives. Particle physics has had a great impact in our society in the last years and has changed the theoretical picture about matter fundamental dynamics. Thus, we think that academic contents about matter components and interactions should be updated. With this study we aim to characterize the level of knowledge of high school students about this topic. We built a test with questions about classical atomic models, particle physics, recent discoveries, social implications and students opinions about it. Contrary to our first suspicion, students’ answers show a high variability. They have new physics ideas and show a great interest towards modern concepts. We suggest including an updated view of this topic as part of the curriculum. PMID:27253377

    3. PREFACE: International Conference on Particle Physics and Astrophysics (ICPPA-2015)

      NASA Astrophysics Data System (ADS)

      2016-02-01

      The International Conference on Particle Physics and Astrophysics (ICPPA-2015) was held in Moscow, Russia, from October 5 to 10, 2015. The conference is organized by Center of Fundamental Research and Particle Physics of National Research Nuclear University ''MEPhI''. The aim of the Conference is to promote contacts between scientists and development of new ideas in fundamental research. We bring together experts and young scientists working on experimental and theoretical aspects of nuclear, particle, astroparticle physics and cosmology. The conference covers a wide range of topics such as accelerator physics, (astro) particle physics, cosmic rays, cosmology and methods of experimental physics - detectors and instruments. These directions are unified by development of the Standard Model (SM) which is evidently not complete. There are deviations from the Standard Model - neutrino oscillations, the dark matter existence. Together with strong interactions, they are main subjects of the Conference. New results from LHC collider as well as its future upgrade are discussed with the Higgs as the main point for discussion. Substantial development of experimental tools for astrophysical observations and new results from cosmic ray experiments is one of the main subjects of the conference. Various aspects of strong interaction are discussed. Among them: Charmonium and Bottomonium states, Flavor physics at Super B factories, Exotic Nuclei in Astrophysics. Another subject for discussion is the neutrino physics, promising and unique way to get new knowledge. In this content, several talks on BOREXINO experiment where new results in neutrino oscillations are presented. Special session is devoted to PAMELA experiment - 9 years in orbit and to the future GAMMA-400 gamma-ray telescope with following main scientific goals: indirect dark matter origin study by the gamma-ray astronomy methods, discrete astrophysical sources observations, diffuse background γ-emission analysis

    4. On the fundamental role of dynamics in quantum physics

      NASA Astrophysics Data System (ADS)

      Hofmann, Holger F.

      2016-05-01

      Quantum theory expresses the observable relations between physical properties in terms of probabilities that depend on the specific context described by the "state" of a system. However, the laws of physics that emerge at the macroscopic level are fully deterministic. Here, it is shown that the relation between quantum statistics and deterministic dynamics can be explained in terms of ergodic averages over complex valued probabilities, where the fundamental causality of motion is expressed by an action that appears as the phase of the complex probability multiplied with the fundamental constant ħ. Importantly, classical physics emerges as an approximation of this more fundamental theory of motion, indicating that the assumption of a classical reality described by differential geometry is merely an artefact of an extrapolation from the observation of macroscopic dynamics to a fictitious level of precision that does not exist within our actual experience of the world around us. It is therefore possible to completely replace the classical concepts of trajectories with the more fundamental concept of action phase probabilities as a universally valid description of the deterministic causality of motion that is observed in the physical world.

    5. Parameter estimation of fractional-order chaotic systems by using quantum parallel particle swarm optimization algorithm.

      PubMed

      Huang, Yu; Guo, Feng; Li, Yongling; Liu, Yufeng

      2015-01-01

      Parameter estimation for fractional-order chaotic systems is an important issue in fractional-order chaotic control and synchronization and could be essentially formulated as a multidimensional optimization problem. A novel algorithm called quantum parallel particle swarm optimization (QPPSO) is proposed to solve the parameter estimation for fractional-order chaotic systems. The parallel characteristic of quantum computing is used in QPPSO. This characteristic increases the calculation of each generation exponentially. The behavior of particles in quantum space is restrained by the quantum evolution equation, which consists of the current rotation angle, individual optimal quantum rotation angle, and global optimal quantum rotation angle. Numerical simulation based on several typical fractional-order systems and comparisons with some typical existing algorithms show the effectiveness and efficiency of the proposed algorithm.

    6. Space-Based Research in Fundamental Physics and Quantum Technologies

      NASA Astrophysics Data System (ADS)

      Turyshev, Slava G.; Israelsson, Ulf E.; Shao, Michael; Yu, Nan; Kusenko, Alexander; Wright, Edward L.; Everitt, C. W. Francis; Kasevich, Mark; Lipa, John A.; Mester, John C.; Reasenberg, Robert D.; Walsworth, Ronald L.; Ashby, Neil; Gould, Harvey; Paik, Ho Jung

      Space offers unique experimental conditions and a wide range of opportunities to explore the foundations of modern physics with an accuracy far beyond that of ground-based experiments. Space-based experiments today can uniquely address important questions related to the fundamental laws of Nature. In particular, high-accuracy physics experiments in space can test relativistic gravity and probe the physics beyond the Standard Model; they can perform direct detection of gravitational waves and are naturally suited for investigations in precision cosmology and astroparticle physics. In addition, atomic physics has recently shown substantial progress in the development of optical clocks and atom interferometers. If placed in space, these instruments could turn into powerful high-resolution quantum sensors greatly benefiting fundamental physics. We discuss the current status of space-based research in fundamental physics, its discovery potential, and its importance for modern science. We offer a set of recommendations to be considered by the upcoming National Academy of Sciences' Decadal Survey in Astronomy and Astrophysics. In our opinion, the Decadal Survey should include space-based research in fundamental physics as one of its focus areas. We recommend establishing an Astronomy and Astrophysics Advisory Committee's interagency "Fundamental Physics Task Force" to assess the status of both ground- and space-based efforts in the field, to identify the most important objectives, and to suggest the best ways to organize the work of several federal agencies involved. We also recommend establishing a new NASA-led interagency program in fundamental physics that will consolidate new technologies, prepare key instruments for future space missions, and build a strong scientific and engineering community. Our goal is to expand NASA's science objectives in space by including "laboratory research in fundamental physics" as an element in the agency's ongoing space research efforts.

    7. PREFACE: The 9th Biennial Conference on Classical and Quantum Relativistic Dynamics of Particles and Fields

      NASA Astrophysics Data System (ADS)

      Horwitz, L. P.

      2015-05-01

      The most recent meeting took place at the University of Connecticut, Storrs, on June 9-13, 2014. This meeting forms the basis for the Proceedings that are recorded in this issue of the Journal of Physics: Conference Series. Along with the work of some of the founding members of the Association, we were fortunate to have lecturers from application areas that provided strong challenges for further developments in quantum field theory, cosmological problems, and in the dynamics of systems subject to accelerations and the effects of general relativity. Topics treated in this issue include studies of the dark matter problem, rotation curves, and, in particular, for the (relatively accessible) Milky Way galaxy, compact stellar objects, a composite particle model, and the properties of a conformally invariant theory with spontaneous symmetry breaking. The Stueckelberg theory is further investigated for its properties in producing bremsstrahlung and pair production and apparent superluminal effects, and, as mentioned above, the implications of low energy nuclear reactions for such off-shell theories. Other "proper time" theories are investigated as well, and a study of the clock synchronization problem is presented. A mathematical study of to quantum groupo associated with the Toda lattice and its implications for quantum field theory, as well as a phenomenological discussion of supernova mechanics as well as a semiclassical discussion of electron spin and the question of the compatibility of special relativity and the quantum theory. A careful analysis of the covariant Aharonov-Bohm effect is given as well. The quantization of massless fields and the relation to the Maxwell theory is also discussed. We wish to thank the participants who contributed very much through their lectures, personal discussions, and these papers, to the advancement of the subject and our understanding.

    8. Ensembles of physical states and random quantum circuits on graphs

      NASA Astrophysics Data System (ADS)

      Hamma, Alioscia; Santra, Siddhartha; Zanardi, Paolo

      2012-11-01

      In this paper we continue and extend the investigations of the ensembles of random physical states introduced in Hamma [Phys. Rev. Lett.PRLTAO0031-900710.1103/PhysRevLett.109.040502 109, 040502 (2012)]. These ensembles are constructed by finite-length random quantum circuits (RQC) acting on the (hyper)edges of an underlying (hyper)graph structure. The latter encodes for the locality structure associated with finite-time quantum evolutions generated by physical, i.e., local, Hamiltonians. Our goal is to analyze physical properties of typical states in these ensembles; in particular here we focus on proxies of quantum entanglement as purity and α-Renyi entropies. The problem is formulated in terms of matrix elements of superoperators which depend on the graph structure, choice of probability measure over the local unitaries, and circuit length. In the α=2 case these superoperators act on a restricted multiqubit space generated by permutation operators associated to the subsets of vertices of the graph. For permutationally invariant interactions the dynamics can be further restricted to an exponentially smaller subspace. We consider different families of RQCs and study their typical entanglement properties for finite time as well as their asymptotic behavior. We find that area law holds in average and that the volume law is a typical property (that is, it holds in average and the fluctuations around the average are vanishing for the large system) of physical states. The area law arises when the evolution time is O(1) with respect to the size L of the system, while the volume law arises as is typical when the evolution time scales like O(L).

    9. How to upload a physical quantum state into correlation space

      SciTech Connect

      Morimae, Tomoyuki

      2011-04-15

      In the framework of the computational tensor network [Phys. Rev. Lett. 98, 220503 (2007)], the quantum computation is performed in a virtual linear space called the correlation space. It was recently shown [Phys. Rev. Lett. 103, 050503 (2009)] that a state in a correlation space can be downloaded to the real physical space. In this paper, conversely, we study how to upload a state from a real physical space to the correlation space. After showing the impossibility of cloning a state between a real physical space and the correlation space, we propose a simple teleportation-like method of uploading. This method also enables the Gottesman-Chuang gate teleportation trick and entanglement swapping in the virtual-real hybrid setting. Furthermore, compared with the inverse of the downloading method by Cai et al. [Phys. Rev. Lett. 103, 050503 (2009)], which also works to upload, the proposed uploading method has several advantages.

    10. Hidden symmetries of dynamics in classical and quantum physics

      NASA Astrophysics Data System (ADS)

      Cariglia, Marco

      2014-10-01

      This article reviews the role of hidden symmetries of dynamics in the study of physical systems, from the basic concepts of symmetries in phase space to the forefront of current research. Such symmetries emerge naturally in the description of physical systems as varied as nonrelativistic, relativistic, with or without gravity, classical or quantum, and are related to the existence of conserved quantities of the dynamics and integrability. In recent years their study has grown intensively, due to the discovery of nontrivial examples that apply to different types of theories and different numbers of dimensions. Applications encompass the study of integrable systems such as spinning tops, the Calogero model, systems described by the Lax equation, the physics of higher-dimensional black holes, the Dirac equation, and supergravity with and without fluxes, providing a tool to probe the dynamics of nonlinear systems.

    11. Physical realization of quantum teleportation for a nonmaximal entangled state

      SciTech Connect

      Tanaka, Yoshiharu; Asano, Masanari; Ohya, Masanori

      2010-08-15

      Recently, Kossakowski and Ohya (K-O) proposed a new teleportation scheme which enables perfect teleportation even for a nonmaximal entangled state [A. Kossakowski and M. Ohya, Infinite Dimensional Analysis Quantum Probability and Related Topics 10, 411 (2007)]. To discuss a physical realization of the K-O scheme, we propose a model based on quantum optics. In our model, we take a superposition of Schroedinger's cat states as an input state being sent from Alice to Bob, and their entangled state is generated by a photon number state through a beam splitter. When the average photon number for our input states is equal to half the number of photons into the beam splitter, our model has high fidelity.

    12. Physical realization of quantum teleportation for a nonmaximal entangled state

      NASA Astrophysics Data System (ADS)

      Tanaka, Yoshiharu; Asano, Masanari; Ohya, Masanori

      2010-08-01

      Recently, Kossakowski and Ohya (K-O) proposed a new teleportation scheme which enables perfect teleportation even for a nonmaximal entangled state [A. Kossakowski and M. Ohya, Infinite Dimensional Analysis Quantum Probability and Related Topics0219-025710.1142/S021902570700283X 10, 411 (2007)]. To discuss a physical realization of the K-O scheme, we propose a model based on quantum optics. In our model, we take a superposition of Schrödinger’s cat states as an input state being sent from Alice to Bob, and their entangled state is generated by a photon number state through a beam splitter. When the average photon number for our input states is equal to half the number of photons into the beam splitter, our model has high fidelity.

    13. A brief survey of the mathematics of quantum physics

      NASA Astrophysics Data System (ADS)

      Bohm, Arno; Uncu, Haydar; Komy, S.

      2009-08-01

      The mathematics of quantum physics started from matrices and from differential operators. It inspired the theory of linear operators in Hilbert space and of unitary representation for symmetry groups and spectrum generating groups. The Dirac bra-ket formalism led first to Schwartz's theory of distributions and then to its generalization, the Rigged Hilbert Space (RHS) or Gelfand triplet. This Schwartz-RHS provided the mathematical justification for Dirac's continuous basis vector expansion and for the algebra of continuous observables of quantum theory. To obtain also a mathematical theory of scattering, resonance and decay phenomena one needed to make a mathematical distinction between prepared in-states and detected observables ("out-states"). This leads to a pair of Hardy RHS's and using the Paley-Wiener theorem, to solutions of the dynamical equations (Schrödinger or Heisenberg) given by time-asymmetric semi-groups, expressing Einstein causality.

    14. Physical facets of ultrasonic cavitational synthesis of zinc ferrite particles.

      PubMed

      Reddy, Bhaskar Rao; Sivasankar, Thirugnanasambandam; Sivakumar, Manickam; Moholkar, Vijayanand S

      2010-02-01

      This paper addresses the physical features of the ultrasonic cavitational synthesis of zinc ferrite particles and tries to establish the relationship between cavitation physics and sonochemistry of the zinc ferrite synthesis. A dual approach of coupling experimental results with simulations of radial motion of cavitation bubbles has been adopted. The precursors for the zinc ferrite, viz. ZnO and Fe(3)O(4) are produced in situ by the hydrolysis of Zn and Fe(II) acetates stimulated by (*)OH radicals produced from the transient collapse of the cavitation bubbles. Experiments performed under different conditions create significant variation in the production of (*)OH radicals, and hence, the rate of acetate hydrolysis. Correlation of the results of experiments and simulations sheds light on the important facets of the physical mechanism of ultrasonic cavitational zinc ferrite synthesis. It is revealed that too much or too little rate of acetate hydrolysis results in smaller particle size of zinc ferrite. The first effect of a higher rate of hydrolysis leads to excessively large growth of particles, due to which they become susceptible to the disruptive action of cavitation bubbles. Whereas, the second effect of too small rate of hydrolysis of Zn and Fe(II) acetates restricts the growth of particles. It has been observed that the initial reactant concentration does not influence the mean particle size or the size distribution of zinc ferrite particles. The present investigation clearly confirms that the rate-controlling step of zinc ferrite synthesis through ultrasonic cavitational route is the rate of formation of (*)OH radicals from cavitation bubbles.

    15. Quantum electrodynamics analysis of optical binding in counterpropagating beams and effect of particle size.

      PubMed

      Rodriguez, Justo

      2008-10-01

      A general expression for optical binding energy between particles of any size, in counterpropagating beams with and without interference, is derived using quantum electrodynamics. The effect of particle size on the optically induced interparticle energy surface, which has been the subject of recent research, is explored. Significant changes in this surface when particle size approaches the wavelength of the optical field are revealed. Finally, optically induced particle arrays that may be fabricated with these potentials are briefly discussed.

    16. BOOK REVIEW: The Quantum Mechanics Solver: How to Apply Quantum Theory to Modern Physics, 2nd edition

      NASA Astrophysics Data System (ADS)

      Robbin, J. M.

      2007-07-01

      he hallmark of a good book of problems is that it allows you to become acquainted with an unfamiliar topic quickly and efficiently. The Quantum Mechanics Solver fits this description admirably. The book contains 27 problems based mainly on recent experimental developments, including neutrino oscillations, tests of Bell's inequality, Bose Einstein condensates, and laser cooling and trapping of atoms, to name a few. Unlike many collections, in which problems are designed around a particular mathematical method, here each problem is devoted to a small group of phenomena or experiments. Most problems contain experimental data from the literature, and readers are asked to estimate parameters from the data, or compare theory to experiment, or both. Standard techniques (e.g., degenerate perturbation theory, addition of angular momentum, asymptotics of special functions) are introduced only as they are needed. The style is closer to a non-specialist seminar rather than an undergraduate lecture. The physical models are kept simple; the emphasis is on cultivating conceptual and qualitative understanding (although in many of the problems, the simple models fit the data quite well). Some less familiar theoretical techniques are introduced, e.g. a variational method for lower (not upper) bounds on ground-state energies for many-body systems with two-body interactions, which is then used to derive a surprisingly accurate relation between baryon and meson masses. The exposition is succinct but clear; the solutions can be read as worked examples if you don't want to do the problems yourself. Many problems have additional discussion on limitations and extensions of the theory, or further applications outside physics (e.g., the accuracy of GPS positioning in connection with atomic clocks; proton and ion tumor therapies in connection with the Bethe Bloch formula for charged particles in solids). The problems use mainly non-relativistic quantum mechanics and are organised into three

    17. Numerical simulation of quantum systems using the Particle-In-Cell method

      NASA Astrophysics Data System (ADS)

      Dirkmann, Sven; Youssef, Ziad; Hemke, Torben; Mussenbrock, Thomas

      2014-10-01

      The Particle-In-Cell (PIC) method is a very powerful method for studying the dynamics of plasmas. It has been primarily developed for tracking the charged particle trajectories subject to selfconsistent and external electromagnetic fields. Exploiting the power of modern computers, one is able to track the classical paths of tens of millions of particles at the same time. In the late 1980th, it was Dawson (and later Dauger) who had the idea to apply the PIC method to the classical part in the semiclassical approach to quantum systems via path integral methods. One could estimate that if a thousands of classical paths are sufficient to describe the dynamics of one quantum particle, then millions classical paths could describe the dynamics of a quantum particle system. A PIC code in the frame of a semiclassical approach would therefore enable the investigation of a number of quantum phenomena, e.g., optical properties, electrical properties, and, ultimately, chemical reactions. In this contribution we explain the use of the PIC code yapic (developed by the authors) in the frame of the path integral method and discuss the numerical results for simple quantum phenomena, i.e., the quantum harmonic oscillator and quantum tunneling. This work is supported by the German Research Foundation in the frame of FOR 2093.

    18. A guide to experimental particle physics literature, 1991-1996

      SciTech Connect

      Ezhela, V.V.; Filimonov, B.B.; Lugovsky, S.B.

      1996-10-01

      We present an indexed guide to experimental particle physics literature for the years 1991 - 1996. Approximately 4200 papers are indexed by (1) Beam/Target/Momentum (2) Reaction/Momentum/Data-Descriptor (including the final state) (3) Particle/Decay (4) Accelerator/Experiment/Detector. All indices are cross-referenced to the paper`s title and references in the ID/Reference/Title index. The information presented in this guide is also publicly available on a regularly-updated DATAGUIDE database from the World Wide Web.

    19. Linear stochastic electrodynamics: Looking for the physics behind quantum theory

      NASA Astrophysics Data System (ADS)

      de la Peña, Luis; Cetto, Ana María

      1999-03-01

      In this chapter, which covers part of the course given at ELAF, a straight-forward procedure is presented that leads from the basic postulates of stochastic electrodynamics to the usual formalism of quantum theory. The theory thus developed is called linear stochastic electrodynamics, to underline that one of its basic features is the (asymptotic) linear response of atomic systems to the background field. The chapter starts with a brief discussion of some open questions in quantum theory and of the possibility to find an answer to them by resorting to the zeropoint radiation field as the source of the quantum behavior of matter. The basic properties of this field are discussed, and a brief enumeration is made of some of the positive results and vital shortcomings of standard stochastic electrodynamics. After identifying the source of these shortcomings in the assumption that the background field is not altered by its interaction with matter, linear stochastic electrodynamics is developed and shown to lead, under certain approximations, to a consistent picture of both matter and field quantization. In the concluding part, it is shown that also the electron spin can be considered to be generated by the interaction of the particle with the zeropoint field; in particular, the two-valuedness of the spin projection is associated with the existence of just two independent states of polarization of the field.

    20. The physical underpinning of security proofs for quantum key distribution

      NASA Astrophysics Data System (ADS)

      Boileau, Jean Christian

      The dawn of quantum technology unveils a plethora of new possibilities and challenges in the world of information technology, one of which is the quest for secure information transmission. A breakthrough in classical algorithm or the development of a quantum computer could threaten the security of messages encoded using public key cryptosystems based on one-way function such as RSA. Quantum key distribution (QKD) offers an unconditionally secure alternative to such schemes, even in the advent of a quantum computer, as it does not rely on mathematical or technological assumptions, but rather on the universality of the laws of quantum mechanics. Physical concepts associated with quantum mechanics, like the uncertainty principle or entanglement, paved the way to the first successful security proof for QKD. Ever since, further development in security proofs for QKD has been remarkable. But the connection between entanglement distillation and the uncertainty principle has remained hidden under a pile of mathematical burden. Our main goal is to dig the physics out of the new advances in security proofs for QKD. By introducing an alternative definition of private state, which elaborates the ideas of Mayers and Koashi, we explain how the security of all QKD protocols follows from an entropic uncertainty principle. We show explicitly how privacy amplification protocol can be reduced to a private state distillation protocol constructed from our observations about the uncertainty principle. We also derive a generic security proof for one-way permutation-invariant QKD protocols. Considering collective attack, we achieve the same secret key generation rate as the Devetak-Winter's bound. Generalizing an observation from Kraus, Branciard and Renner, we have provided an improved version of the secret key generation rates by considering a different symmetrization. In certain situations, we argue that Azuma's inequality can simplify the security proof considerably, and we explain

    1. REVIEWS OF TOPICAL PROBLEMS: Hadron clusters and half-dressed particles in quantum field theory

      NASA Astrophysics Data System (ADS)

      Feĭnberg, E. L.

      1980-10-01

      Accelerator experiments show that multiple production of hadrons in high-energy collisions of particles involves the formation of unstable intermediate entities, which subsequently decay into the final hadrons. These entities are apparently not only the comparatively light resonances with which we are already familiar but also heavy nonresonant clusters (with a mass above 2-5 GeV). The cluster concept was introduced previously in cosmic-ray physics, under the name "fireballs". To determine what these clusters are from the standpoint of quantum field theory, a detailed and thorough analysis is made of some analogous processes in quantum electrodynamics which are amenable to calculation. The QED analogs of the nonresonant clusters are "half-dressed" electrons and heavy photons. The half-dressed electrons decay into photons and electrons and are completely observable entities, whose interaction properties distinguish them from dressed electrons. In other words, the nonresonant particles are generally off-shell particles (the excursion from the mass shell is in the timelike direction). The assumption that hadron clusters are only resonances would be equivalent to a very specialized assumption regarding the nature of the spectral function of the hadron propagator; it would be different from that in electrodynamics, where the spectral function can be calculated. Nonresonant hadron clusters thus fit naturally into hadron field theory and are nonequilibrium hadrons far from the mass shell in the timelike direction. (In certain cases, their structural distortion is of the same nature as that of a half-dressed electron, so that this term can be conventionally applied to them as well.

    2. The Relation between Fundamental Constants and Particle Physics Parameters

      NASA Astrophysics Data System (ADS)

      Thompson, Rodger

      2017-01-01

      The observed constraints on the variability of the proton to electron mass ratio $\\mu$ and the fine structure constant $\\alpha$ are used to establish constraints on the variability of the Quantum Chromodynamic Scale and a combination of the Higgs Vacuum Expectation Value and the Yukawa couplings. Further model dependent assumptions provide constraints on the Higgs VEV and the Yukawa couplings separately. A primary conclusion is that limits on the variability of dimensionless fundamental constants such as $\\mu$ and $\\alpha$ provide important constraints on the parameter space of new physics and cosmologies.

    3. Searching for new physics at the frontiers with lattice quantum chromodynamics.

      PubMed

      Van de Water, Ruth S

      2012-07-01

      Numerical lattice-quantum chromodynamics (QCD) simulations, when combined with experimental measurements, allow the determination of fundamental parameters of the particle-physics Standard Model and enable searches for physics beyond-the-Standard Model. We present the current status of lattice-QCD weak matrix element calculations needed to obtain the elements and phase of the Cabibbo-Kobayashi-Maskawa (CKM) matrix and to test the Standard Model in the quark-flavor sector. We then discuss evidence that may hint at the presence of new physics beyond the Standard Model CKM framework. Finally, we discuss two opportunities where we expect lattice QCD to play a pivotal role in searching for, and possibly discovery of, new physics at upcoming high-intensity experiments: rare decays and the muon anomalous magnetic moment. The next several years may witness the discovery of new elementary particles at the Large Hadron Collider (LHC). The interplay between lattice QCD, high-energy experiments at the LHC, and high-intensity experiments will be needed to determine the underlying structure of whatever physics beyond-the-Standard Model is realized in nature.

    4. MAJOR DETECOTRS IN ELEMENTARY PARTICLE PHYSICS - May 1985 Suppl.

      SciTech Connect

      Gidal, G.; Armstrong, B.; Rittenberg, A.

      1985-05-01

      This report is the second edition of a loose-leaf compendium of the properties and performance characteristics of the major detectors of elementary particle physics. This introduces the second edition of the LBL-91 Supplement 'Major Detectors in Elementary Particle Physics.' For some detectors the update merely documents minor modifications or provides additional references. Others have undergone major rebuilding or have been augmented with new subsystems. The new LEP, SLC, TRISTAN, BEPC, and FNAL detectors have had their designs fixed and are now under construction. Some detectors have completed their programs since the last edition and so are omitted. The use of colored loose-leaf paper should allow users to maintain a historical record of each detector. We again thank those physicists working with each detector who took the time to summarize its properties and supply us with the appropriate drawings.

    5. UCLA Particle Physics Research Group annual progress report

      SciTech Connect

      Nefkens, B.M.K.

      1983-11-01

      The objectives, basic research programs, recent results, and continuing activities of the UCLA Particle Physics Research Group are presented. The objectives of the research are to discover, to formulate, and to elucidate the physics laws that govern the elementary constituents of matter and to determine basic properties of particles. The research carried out by the Group last year may be divided into three separate programs: (1) baryon spectroscopy, (2) investigations of charge symmetry and isospin invariance, and (3) tests of time reversal invariance. The main body of this report is the account of the techniques used in our investigations, the results obtained, and the plans for continuing and new research. An update of the group bibliography is given at the end.

    6. Materials for Active Engagement in Nuclear and Particle Physics Courses

      NASA Astrophysics Data System (ADS)

      Loats, Jeff; Schwarz, Cindy; Krane, Ken

      2013-04-01

      Physics education researchers have developed a rich variety of research-based instructional strategies that now permeate many introductory courses. Carrying these active-engagement techniques to upper-division courses requires effort and is bolstered by experience. Instructors interested in these methods thus face a large investment of time to start from scratch. This NSF-TUES grant, aims to develop, test and disseminate active-engagement materials for nuclear and particle physics topics. We will present examples of these materials, including: a) Conceptual discussion questions for use with Peer Instruction; b) warm-up questions for use with Just in Time Teaching, c) ``Back of the Envelope'' estimation questions and small-group case studies that will incorporate use of nuclear and particle databases, as well as d) conceptual exam questions.

    7. Physical sputtering of metallic systems by charged-particle impact

      SciTech Connect

      Lam, N.Q.

      1989-12-01

      The present paper provides a brief overview of our current understanding of physical sputtering by charged-particle impact, with the emphasis on sputtering of metals and alloys under bombardment with particles that produce knock-on collisions. Fundamental aspects of ion-solid interactions, and recent developments in the study of sputtering of elemental targets and preferential sputtering in multicomponent materials are reviewed. We concentrate only on a few specific topics of sputter emission, including the various properties of the sputtered flux and depth of origin, and on connections between sputtering and other radiation-induced and -enhanced phenomena that modify the near-surface composition of the target. The synergistic effects of these diverse processes in changing the composition of the integrated sputtered-atom flux is described in simple physical terms, using selected examples of recent important progress. 325 refs., 27 figs.

    8. The quantum charged particle self-interaction problem within the Fock many temporal and Feynman proper time paradigms

      NASA Astrophysics Data System (ADS)

      Prykarpatski, A. K.; Bogolubov, N. N.

      2017-01-01

      A quantum fermionic massless charged particle self-intercating with its own self-generated bosonic electromagnetic field is reanalyzed in the framework of the Fock many-temporal and Feynman proper time approaches. The self-interaction phenomenon structure is discussed within the renormalized quantum Fock space. The quantum electromagnetic charged particle mass origin is suggested.

    9. Particle physics catalysis of thermal big bang nucleosynthesis.

      PubMed

      Pospelov, Maxim

      2007-06-08

      We point out that the existence of metastable, tau>10(3) s, negatively charged electroweak-scale particles (X-) alters the predictions for lithium and other primordial elemental abundances for A>4 via the formation of bound states with nuclei during big bang nucleosynthesis. In particular, we show that the bound states of X- with helium, formed at temperatures of about T=10(8) K, lead to the catalytic enhancement of 6Li production, which is 8 orders of magnitude more efficient than the standard channel. In particle physics models where subsequent decay of X- does not lead to large nonthermal big bang nucleosynthesis effects, this directly translates to the level of sensitivity to the number density of long-lived X- particles (tau>10(5) s) relative to entropy of nX-/s less, approximately <3x10(-17), which is one of the most stringent probes of electroweak scale remnants known to date.

    10. A convergence: special relativity, zitterbewegung, and new models for the subcomponent structure of quantum particles

      NASA Astrophysics Data System (ADS)

      Mobley, Michael J.

      2015-09-01

      Hestenes has presented an integration of Schrödinger's zitterbewegung with the spin matrices of the Dirac equation, suggesting the electron can be modeled by a rapidly rotating dipole moment and a frequency related to the de Broglie frequency. He presents an elegant spacetime algebra that provides a reformulation of the Dirac equation that incorporates these real spin characteristics. A similar heuristic model for quantum particles has been derived by this author from a different, quasi-classical premise: That the most fundamental subcomponents of quantum particles all travel at a constant speed of light. Time is equated with the spatial displacement of these subcomponents - the speed of light is the speed of time. This approach suggests a means of integrating special relativity and quantum mechanics with the same concept of time. The relativistic transformation of spinning quantum particles create the appearance of additional, compactified spatial dimensions that can be correlated with the complex phase of the spin matrices as in the Dirac formalism. This paper further examines the convergence on such new models for quantum particles built on this rapid motion of particle subcomponents. The modeling leverages a string-like heuristic for particle subcomponents and a revised description for the wave-like properties of particles. This examination provides useful insights to the real spatial geometries and interactions of electrons and photons.

    11. The use of minimal spanning trees in particle physics

      NASA Astrophysics Data System (ADS)

      Lovelace Rainbolt, J.; Schmitt, M.

      2017-02-01

      Minimal spanning trees (MSTs) have been used in cosmology and astronomy to distinguish distributions of points in a multi-dimensional space. They are essentially unknown in particle physics, however. We briefly define MSTs and illustrate their properties through a series of examples. We show how they might be applied to study a typical event sample from a collider experiment and conclude that MSTs may prove useful in distinguishing different classes of events.

    12. Current experiments in elementary-particle physics - March 1983

      SciTech Connect

      Wohl, C.G.; Armstrong, F.E.; Rittenberg, A.

      1983-03-01

      Microfiche are included which contain summaries of 479 experiments in elementary particle physics. Experiments are included at the following laboratories: Brookhaven (BNL); CERN; CESR; DESY; Fermilab (FNAL); Institute for Nuclear Studies (INS); KEK; LAMPF; Serpukhov (SERP); SIN; SLAC; and TRIUMF. Also, summaries of proton decay experiments are included. A list of experiments and titles is included; and a beam-target-momentum index and a spokesperson index are given. Properties of beams at the facilities are tabulated. (WHK)

    13. A Novel Quantum Blind Signature Scheme with Four-Particle Cluster States

      NASA Astrophysics Data System (ADS)

      Fan, Ling

      2016-03-01

      In an arbitrated quantum signature scheme, the signer signs the message and the receiver verifies the signature's validity with the assistance of the arbitrator. We present an arbitrated quantum blind signature scheme by measuring four-particle cluster states and coding. By using the special relationship of four-particle cluster states, we cannot only support the security of quantum signature, but also guarantee the anonymity of the message owner. It has a wide application to E-payment system, E-government, E-business, and etc.

    14. A Novel Quantum Blind Signature Scheme with Four-particle GHZ States

      NASA Astrophysics Data System (ADS)

      Fan, Ling; Zhang, Ke-Jia; Qin, Su-Juan; Guo, Fen-Zhuo

      2016-02-01

      In an arbitrated quantum signature scheme, the signer signs the message and the receiver verifies the signature's validity with the assistance of the arbitrator. We present an arbitrated quantum blind signature scheme by using four-particle entangled Greenberger-Horne-Zeilinger (GHZ) states. By using the special relationship of four-particle GHZ states, we cannot only support the security of quantum signature, but also guarantee the anonymity of the message owner. It has a wide application to E-payment system, E-government, E-business, and etc.

    15. Two-particle quantum interference in tunnel-coupled optical tweezers.

      PubMed

      Kaufman, A M; Lester, B J; Reynolds, C M; Wall, M L; Foss-Feig, M; Hazzard, K R A; Rey, A M; Regal, C A

      2014-07-18

      The quantum statistics of atoms is typically observed in the behavior of an ensemble via macroscopic observables. However, quantum statistics modifies the behavior of even two particles. Here, we demonstrate near-complete control over all the internal and external degrees of freedom of two laser-cooled (87)Rb atoms trapped in two optical tweezers. This controllability allows us to observe signatures of indistinguishability via two-particle interference. Our work establishes laser-cooled atoms in optical tweezers as a promising route to bottom-up engineering of scalable, low-entropy quantum systems.

    16. Theoretical and Experimental Studies of Elementary Particle Physics

      SciTech Connect

      Evans, Harold G; Kostelecky, V Alan; Musser, James A

      2013-07-29

      The elementary particle physics research program at Indiana University spans a broad range of the most interesting topics in this fundamental field, including important contributions to each of the frontiers identified in the recent report of HEPAP's Particle Physics Prioritization Panel: the Energy Frontier, the Intensity Frontier, and the Cosmic Frontier. Experimentally, we contribute to knowledge at the Energy Frontier through our work on the D0 and ATLAS collaborations. We work at the Intensity Frontier on the MINOS and NOvA experiments and participate in R&D for LBNE. We are also very active on the theoretical side of each of these areas with internationally recognized efforts in phenomenology both in and beyond the Standard Model and in lattice QCD. Finally, although not part of this grant, members of the Indiana University particle physics group have strong involvement in several astrophysics projects at the Cosmic Frontier. Our research efforts are divided into three task areas. The Task A group works on D0 and ATLAS; Task B is our theory group; and Task C contains our MINOS, NOvA, and LBNE (LArTPC) research. Each task includes contributions from faculty, senior scientists, postdocs, graduate and undergraduate students, engineers, technicians, and administrative personnel. This work was supported by DOE Grant DE-FG02-91ER40661. In the following, we describe progress made in the research of each task during the final period of the grant, from November 1, 2009 to April 30, 2013.

    17. Cherenkov light imaging in astro-particle physics

      NASA Astrophysics Data System (ADS)

      Mirzoyan, Razmik

      2014-12-01

      Cherenkov light emission plays a key role in contemporary science; it is widely used in high energy, nuclear, and numerous astro-particle physics experiments. Most astro-particle physics experiments are based on the detection of light, and a vast majority of them on the measurement of Cherenkov light. Cherenkov light emission is measured in gases (used in air-Cherenkov technique), in water (for example, neutrino experiments BAIKAL, Super-Kamiokande, NESTOR, ANTARES, future KM3NeT; cosmic and γ-ray experiments Milagro, HAWC, AUGER) and in ice (IceCube). In this report our goal is not limited to simply listing the multitude of experiments that are based on using Cherenkov emission, but we will clarify the reasons making this emission so important and so frequently used. For completeness we will first give a short historical overview on the discovery and evolution of Cherenkov emission and then we will dwell on its main features and numerous applications in astro-particle physics experiments.

    18. Tomonaga-Luttinger physics in electronic quantum circuits.

      PubMed

      Jezouin, S; Albert, M; Parmentier, F D; Anthore, A; Gennser, U; Cavanna, A; Safi, I; Pierre, F

      2013-01-01

      In one-dimensional conductors, interactions result in correlated electronic systems. At low energy, a hallmark signature of the so-called Tomonaga-Luttinger liquids is the universal conductance curve predicted in presence of an impurity. A seemingly different topic is the quantum laws of electricity, when distinct quantum conductors are assembled in a circuit. In particular, the conductances are suppressed at low energy, a phenomenon called dynamical Coulomb blockade. Here we investigate the conductance of mesoscopic circuits constituted by a short single-channel quantum conductor in series with a resistance, and demonstrate a proposed link to Tomonaga-Luttinger physics. We reformulate and establish experimentally a recently derived phenomenological expression for the conductance using a wide range of circuits, including carbon nanotube data obtained elsewhere. By confronting both conductance data and phenomenological expression with the universal Tomonaga-Luttinger conductance curve, we demonstrate experimentally the predicted mapping between dynamical Coulomb blockade and the transport across a Tomonaga-Luttinger liquid with an impurity.

    19. The neutron and its role in cosmology and particle physics

      SciTech Connect

      Dubbers, Dirk; Schmidt, Michael G.

      2011-10-01

      Experiments with cold and ultracold neutrons have reached a level of precision such that problems far beyond the scale of the present standard model of particle physics become accessible to experimental investigation. Because of the close links between particle physics and cosmology, these studies also permit a deep look into the very first instances of our Universe. First addressed in this article, in both theory and experiment, is the problem of baryogenesis, the mechanism behind the evident dominance of matter over antimatter in the Universe. The question of how baryogenesis could have happened is open to experimental tests, and it turns out that this problem can be curbed by the very stringent limits on an electric dipole moment of the neutron, a quantity that also has deep implications for particle physics. Then the recent spectacular observation of neutron quantization in the Earth's gravitational field and of resonance transitions between such gravitational energy states is discussed. These measurements, together with new evaluations of neutron scattering data, set new constraints on deviations from Newton's gravitational law at the picometer scale. Such deviations are predicted in modern theories with extra dimensions that propose unification of the Planck scale with the scale of the standard model. These experiments start closing the remaining ''axion window'' on new spin-dependent forces in the submillimeter range. Another main topic is the weak-interaction parameters in various fields of physics and astrophysics that must all be derived from measured neutron-decay data. Up until now, about 10 different neutron-decay observables have been measured, much more than needed in the electroweak standard model. This allows various precise tests for new physics beyond the standard model, competing with or surpassing similar tests at high energy. The review ends with a discussion of neutron and nuclear data required in the synthesis of the elements during the

    20. Research in particle physics. Progress report, June 1, 1992--January 31, 1993

      SciTech Connect

      Not Available

      1992-09-01

      Research accomplishments and current activities of Boston University researchers in high energy physics are presented. Principal areas of activity include the following: detectors for studies of electron{endash}positron annihilation in colliding beams; advanced accelerator component design, including the superconducting beam inflector, electrostatic quadrupoles, and the ``electrostatic muon kicker``; the detector for the MACRO (Monopole, Astrophysics, and Cosmic Ray Observatory) experiment; neutrino astrophysics and the search for proton decay; theoretical particle physics (electroweak and flavor symmetry breaking, hadron collider phenomenology, cosmology and astrophysics, new field-theoretic models, nonperturbative investigations of quantum field theories, electroweak interactions); measurement of the anomalous magnetic moment of the muon; calorimetry for the GEM experiment; and muon detectors for the GEM experiment at the Superconducting Super Collider.

    1. Two-party quantum key agreement based on four-particle GHZ states

      NASA Astrophysics Data System (ADS)

      He, Ye-Feng; Ma, Wen-Ping

      2016-04-01

      Based on four-particle GHZ states, the double CNOT operation and the delayed measurement technique, a two-party quantum key agreement (QKA) protocols is proposed. The double CNOT operation makes each four-particle GHZ state collapse into two independent quantum states without any entanglement. Furthermore, one party can directly know the two quantum states and the other party can be aware of the two quantum states by using the corresponding measurement. According to the initial states of the two quantum states, two parties can extract the secret keys of each other by using the publicly announced value or by performing the delayed measurement, respectively. Then the protocol achieves the fair establishment of a shared key. The security analysis shows that the new protocol can resist against participant attacks, the Trojan horse attacks and other outsider attacks. Furthermore, the new protocol also has no information leakage problem and has high qubit efficiency.

    2. Two-party quantum key agreement protocol with four-particle entangled states

      NASA Astrophysics Data System (ADS)

      He, Yefeng; Ma, Wenping

      2016-09-01

      Based on four-particle entangled states and the delayed measurement technique, a two-party quantum key agreement protocol is proposed in this paper. In the protocol, two participants can deduce the measurement results of each other’s initial quantum states in terms of the measurement correlation property of four-particle entangled states. According to the corresponding initial quantum states deduced by themselves, two parties can extract the secret keys of each other by using the publicly announced value or by performing the delayed measurement, respectively. This guarantees the fair establishment of a shared key. Since each particle in quantum channel is transmitted only once, the protocol is congenitally free from the Trojan horse attacks. The security analysis shows that the protocol not only can resist against both participant and outsider attacks but also has no information leakage problem. Moreover, it has high qubit efficiency.

    3. EDITORIAL: Focus on Dark Matter and Particle Physics

      NASA Astrophysics Data System (ADS)

      Aprile, Elena; Profumo, Stefano

      2009-10-01

      The quest for the nature of dark matter has reached a historical point in time, with several different and complementary experiments on the verge of conclusively exploring large portions of the parameter space of the most theoretically compelling particle dark matter models. This focus issue on dark matter and particle physics brings together a broad selection of invited articles from the leading experimental and theoretical groups in the field. The leitmotif of the collection is the need for a multi-faceted search strategy that includes complementary experimental and theoretical techniques with the common goal of a sound understanding of the fundamental particle physical nature of dark matter. These include theoretical modelling, high-energy colliders and direct and indirect searches. We are confident that the works collected here present the state of the art of this rapidly changing field and will be of interest to both experts in the topic of dark matter as well as to those new to this exciting field. Focus on Dark Matter and Particle Physics Contents DARK MATTER AND ASTROPHYSICS Scintillator-based detectors for dark matter searches I S K Kim, H J Kim and Y D Kim Cosmology: small-scale issues Joel R Primack Big Bang nucleosynthesis and particle dark matter Karsten Jedamzik and Maxim Pospelov Particle models and the small-scale structure of dark matter Torsten Bringmann DARK MATTER AND COLLIDERS Dark matter in the MSSM R C Cotta, J S Gainer, J L Hewett and T G Rizzo The role of an e+e- linear collider in the study of cosmic dark matter M Battaglia Collider, direct and indirect detection of supersymmetric dark matter Howard Baer, Eun-Kyung Park and Xerxes Tata INDIRECT PARTICLE DARK MATTER SEARCHES:EXPERIMENTS PAMELA and indirect dark matter searches M Boezio et al An indirect search for dark matter using antideuterons: the GAPS experiment C J Hailey Perspectives for indirect dark matter search with AMS-2 using cosmic-ray electrons and positrons B Beischer, P von

    4. Controllable, Hubbard-like Correlated Electron Physics in Oxide Quantum Structures

      DTIC Science & Technology

      2014-11-01

      Report: Controllable, Hubbard-like Correlated Electron Physics in Oxide Quantum Structures This final report summarizes the results obtained in the...project "Controllable, Hubbard-like Correlated Electron Physics in Oxide Quantum Structures ’. Results are reported from experiments and theory of oxide...Box 12211 Research Triangle Park, NC 27709-2211 Oxide Quantum Structures , Correlated Electron Physics REPORT DOCUMENTATION PAGE 11. SPONSOR

    5. Emergent Devil's Staircase without Particle-Hole Symmetry in Rydberg Quantum Gases with Competing Attractive and Repulsive Interactions

      NASA Astrophysics Data System (ADS)

      Lan, Zhihao; Minář, Jiří; Levi, Emanuele; Li, Weibin; Lesanovsky, Igor

      2015-11-01

      The devil's staircase is a fractal structure that characterizes the ground state of one-dimensional classical lattice gases with long-range repulsive convex interactions. Its plateaus mark regions of stability for specific filling fractions which are controlled by a chemical potential. Typically, such a staircase has an explicit particle-hole symmetry; i.e., the staircase at more than half filling can be trivially extracted from the one at less than half filling by exchanging the roles of holes and particles. Here, we introduce a quantum spin chain with competing short-range attractive and long-range repulsive interactions, i.e., a nonconvex potential. In the classical limit the ground state features generalized Wigner crystals that—depending on the filling fraction—are composed of either dimer particles or dimer holes, which results in an emergent complete devil's staircase without explicit particle-hole symmetry of the underlying microscopic model. In our system the particle-hole symmetry is lifted due to the fact that the staircase is controlled through a two-body interaction rather than a one-body chemical potential. The introduction of quantum fluctuations through a transverse field melts the staircase and ultimately makes the system enter a paramagnetic phase. For intermediate transverse field strengths, however, we identify a region where the density-density correlations suggest the emergence of quasi-long-range order. We discuss how this physics can be explored with Rydberg-dressed atoms held in a lattice.

    6. Emergent Devil's Staircase without Particle-Hole Symmetry in Rydberg Quantum Gases with Competing Attractive and Repulsive Interactions.

      PubMed

      Lan, Zhihao; Minář, Jiří; Levi, Emanuele; Li, Weibin; Lesanovsky, Igor

      2015-11-13

      The devil's staircase is a fractal structure that characterizes the ground state of one-dimensional classical lattice gases with long-range repulsive convex interactions. Its plateaus mark regions of stability for specific filling fractions which are controlled by a chemical potential. Typically, such a staircase has an explicit particle-hole symmetry; i.e., the staircase at more than half filling can be trivially extracted from the one at less than half filling by exchanging the roles of holes and particles. Here, we introduce a quantum spin chain with competing short-range attractive and long-range repulsive interactions, i.e., a nonconvex potential. In the classical limit the ground state features generalized Wigner crystals that--depending on the filling fraction--are composed of either dimer particles or dimer holes, which results in an emergent complete devil's staircase without explicit particle-hole symmetry of the underlying microscopic model. In our system the particle-hole symmetry is lifted due to the fact that the staircase is controlled through a two-body interaction rather than a one-body chemical potential. The introduction of quantum fluctuations through a transverse field melts the staircase and ultimately makes the system enter a paramagnetic phase. For intermediate transverse field strengths, however, we identify a region where the density-density correlations suggest the emergence of quasi-long-range order. We discuss how this physics can be explored with Rydberg-dressed atoms held in a lattice.

    7. Observation of quantum particles on a large space-time scale

      NASA Astrophysics Data System (ADS)

      Landau, L. J.

      1994-10-01

      A quantum particle observed on a sufficiently large space-time scale can be described by means of classical particle trajectories. The joint distribution for large-scale multiple-time position and momentum measurements on a nonrelativistic quantum particle moving freely in R v is given by straight-line trajectories with probabilities determined by the initial momentum-space wavefunction. For large-scale toroidal and rectangular regions the trajectories are geodesics. In a uniform gravitational field the trajectories are parabolas. A quantum counting process on free particles is also considered and shown to converge in the large-space-time limit to a classical counting process for particles with straight-line trajectories. If the quantum particle interacts weakly with its environment, the classical particle trajectories may undergo random jumps. In the random potential model considered here, the quantum particle evolves according to a reversible unitary one-parameter group describing elastic scattering off static randomly distributed impurities (a quantum Lorentz gas). In the large-space-time weak-coupling limit a classical stochastic process is obtained with probability one and describes a classical particle moving with constant speed in straight lines between random jumps in direction. The process depends only on the ensemble value of the covariance of the random field and not on the sample field. The probability density in phase space associated with the classical stochastic process satisfies the linear Boltzmann equation for the classical Lorentz gas, which, in the limit h→0, goes over to the linear Landau equation. Our study of the quantum Lorentz gas is based on a perturbative expansion and, as in other studies of this system, the series can be controlled only for small values of the rescaled time and for Gaussian random fields. The discussion of classical particle trajectories for nonrelativistic particles on a macroscopic spacetime scale applies also to

    8. Future directions in particle and nuclear physics at multi-GeV hadron beam facilities

      SciTech Connect

      Geesaman, D.F.

      1993-11-01

      This report contains papers on the following topics in particle and nuclear physics: hadron dynamics; lepton physics; spin physics; hadron and nuclear spectroscopy; hadronic weak interactions; and Eta physics. These papers have been indexed separately elsewhere.

    9. Falling of a quantum particle in an inverse square attractive potential

      NASA Astrophysics Data System (ADS)

      Vasyuta, Vasyl M.; Tkachuk, Volodymyr M.

      2016-12-01

      Evolution of a quantum particle in an inverse square potential is studied by analysis of the equation of motion for . In such a way we identify the conditions of falling of a particle into the center. We demonstrate the existence of a purely quantum limit of falling, namely, a particle does not fall, when the coupling constant is smaller than a certain critical value. Also the time of falling of a particle into the center is estimated. Although there are no stationary energy levels for this potential, we show that there are quasi-stationary states which evolve with being constant in time. Our results are compared with measurements of neutral atoms falling in the electric field of a charged wire. Modifications of the experiment, which may help in observing quantum limit of falling, are proposed.

    10. Quantum secret sharing protocol based on four-dimensional three-particle entangled states

      NASA Astrophysics Data System (ADS)

      Xiang, Yi; Mo, Zhi Wen

      2016-01-01

      In this paper, we proposed a three-party quantum secret sharing (QSS) scheme using four-dimensional three-particle entangled states. In this QSS scheme, each agent can obtain a shadow of the secret key by performing single-particle measurements. Compared with the existing QSS protocol, this scheme has high efficiency and can resist the eavesdropping attack and entangle-measuring attack, which using three-particle entangled states are based on four-dimensional Hilbert space.

    11. Double-slit experiment with single wave-driven particles and its relation to quantum mechanics.

      PubMed

      Andersen, Anders; Madsen, Jacob; Reichelt, Christian; Rosenlund Ahl, Sonja; Lautrup, Benny; Ellegaard, Clive; Levinsen, Mogens T; Bohr, Tomas

      2015-07-01

      In a thought-provoking paper, Couder and Fort [Phys. Rev. Lett. 97, 154101 (2006)] describe a version of the famous double-slit experiment performed with droplets bouncing on a vertically vibrated fluid surface. In the experiment, an interference pattern in the single-particle statistics is found even though it is possible to determine unambiguously which slit the walking droplet passes. Here we argue, however, that the single-particle statistics in such an experiment will be fundamentally different from the single-particle statistics of quantum mechanics. Quantum mechanical interference takes place between different classical paths with precise amplitude and phase relations. In the double-slit experiment with walking droplets, these relations are lost since one of the paths is singled out by the droplet. To support our conclusions, we have carried out our own double-slit experiment, and our results, in particular the long and variable slit passage times of the droplets, cast strong doubt on the feasibility of the interference claimed by Couder and Fort. To understand theoretically the limitations of wave-driven particle systems as analogs to quantum mechanics, we introduce a Schrödinger equation with a source term originating from a localized particle that generates a wave while being simultaneously guided by it. We show that the ensuing particle-wave dynamics can capture some characteristics of quantum mechanics such as orbital quantization. However, the particle-wave dynamics can not reproduce quantum mechanics in general, and we show that the single-particle statistics for our model in a double-slit experiment with an additional splitter plate differs qualitatively from that of quantum mechanics.

    12. 22nd SLAC Summer Institute on Particle Physics: Particle physics, astrophysics and cosmology

      NASA Astrophysics Data System (ADS)

      Chan, J.; Deporcel, L.

      The seven-day school portion of the Institute revolved around the question of dark matter: where is it and what is it? Reviews were given of microlensing searches for baryonic dark matter, of dark matter candidates in the form of neutrinos and exotic particles, and of low-noise detection techniques used to search for the latter. The history of the universe, from the Big Bang to the role of dark matter in the formation of large-scale structure, was also covered. Other lecture series described the astrophysics that might be done with x-ray timing experiments and through the detection of gravitational radiation. As in past years, the lectures each morning were followed by stimulating afternoon discussion sessions, in which students could pursue with the lecturers the topics that most interested them. The Institute concluded with a three-day topical conference covering recent developments in theory and experiment. Highlights from the astrophysical and cosmological arenas included observations of anisotropy in the cosmic microwave background, and of the mysterious gamma-ray bursters. From terrestrial accelerators came tantalizing hints of the top quark and marked improvements in precision electroweak measurements, among many other results. Selected papers are indexed separately for inclusion in the Energy Science and Technology Database.

    13. A physics-motivated Centroidal Voronoi Particle domain decomposition method

      NASA Astrophysics Data System (ADS)

      Fu, Lin; Hu, Xiangyu Y.; Adams, Nikolaus A.

      2017-04-01

      In this paper, we propose a novel domain decomposition method for large-scale simulations in continuum mechanics by merging the concepts of Centroidal Voronoi Tessellation (CVT) and Voronoi Particle dynamics (VP). The CVT is introduced to achieve a high-level compactness of the partitioning subdomains by the Lloyd algorithm which monotonically decreases the CVT energy. The number of computational elements between neighboring partitioning subdomains, which scales the communication effort for parallel simulations, is optimized implicitly as the generated partitioning subdomains are convex and simply connected with small aspect-ratios. Moreover, Voronoi Particle dynamics employing physical analogy with a tailored equation of state is developed, which relaxes the particle system towards the target partition with good load balance. Since the equilibrium is computed by an iterative approach, the partitioning subdomains exhibit locality and the incremental property. Numerical experiments reveal that the proposed Centroidal Voronoi Particle (CVP) based algorithm produces high-quality partitioning with high efficiency, independently of computational-element types. Thus it can be used for a wide range of applications in computational science and engineering.

    14. Research in Neutrino Physics and Particle Astrophysics: Final Technical Report

      SciTech Connect

      Kearns, Edward

      2016-06-30

      The Boston University Neutrino Physics and Particle Astrophysics Group investigates the fundamental laws of particle physics using natural and man-made neutrinos and rare processes such as proton decay. The primary instrument for this research is the massive Super-Kamiokande (SK) water Cherenkov detector, operating since 1996 at the Kamioka Neutrino Observatory, one kilometer underground in a mine in Japan. We study atmospheric neutrinos from cosmic rays, which were first used to discover that neutrinos have mass, as recognized by the 2015 Nobel Prize in Physics. Our latest measurements with atmospheric neutrinos are giving valuable information, complementary to longbaseline experiments, on the ordering of massive neutrino states and as to whether neutrinos violate CP symmetry. We have studied a variety of proton decay modes, including the most frequently predicted modes such as p → e+π0 and p → ν K+, as well as more exotic baryon number violating processes such as dinucleon decay and neutronantineutron oscillation. We search for neutrinos from dark matter annihilation or decay in the universe. Our group has made significant contributions to detector operation, particularly in the area of electronics. Most recently, we have contributed to planning for an upgrade to the SK detector by the addition of gadolinium to the water, which will enable efficient neutron capture detection.

    15. A system for designing and simulating particle physics experiments

      NASA Astrophysics Data System (ADS)

      Żelazny, Roman; Strzałkowski, Piotr

      1987-01-01

      In view of the rapid development of experimental facilities and their costs, the systematic design and preparation of particle physics experiments have become crucial. A software system is proposed as an aid for the experimental designer, mainly for experimental geometry analysis and experimental simulation. The following model is adopted: the description of an experiment is formulated in a language (here called XL) and put by its processor in a data base. The language is based on the entity-relationship-attribute approach. The information contained in the data base can be reported and analysed by an analyser (called XA) and modifications can be made at any time. In particular, the Monte Carlo methods can be used in experiment simulation for both physical phenomena in experimental set-up and detection analysis. The general idea of the system is based on the design concept of ISDOS project information systems. The characteristics of the simulation module are similar to those of the CERN Geant system, but some extensions are proposed. The system could be treated as a component of a greater, integrated software environment for the design of particle physics experiments, their monitoring and data processing.

    16. Liquid xenon detectors for particle physics and astrophysics

      SciTech Connect

      Aprile, E.; Doke, T.

      2010-07-15

      This article reviews the progress made over the last 20 years in the development and applications of liquid xenon detectors in particle physics, astrophysics, and medical imaging experiments. A summary of the fundamental properties of liquid xenon as radiation detection medium, in light of the most current theoretical and experimental information is first provided. After an introduction of the different type of liquid xenon detectors, a review of past, current, and future experiments using liquid xenon to search for rare processes and to image radiation in space and in medicine is given. Each application is introduced with a survey of the underlying scientific motivation and experimental requirements before reviewing the basic characteristics and expected performance of each experiment. Within this decade it appears likely that large volume liquid xenon detectors operated in different modes will contribute to answering some of the most fundamental questions in particle physics, astrophysics, and cosmology, fulfilling the most demanding detection challenges. From detectors based solely on liquid xenon (LXe) scintillation, such as in the MEG experiment for the search of the rare ''{mu}{yields}e{gamma}'' decay, currently the largest liquid xenon detector in operation, and in the XMASS experiment for dark matter detection, to the class of time projection chambers which exploit both scintillation and ionization of LXe, such as in the XENON dark matter search experiment and in the Enriched Xenon Observatory for neutrinoless double beta decay, unrivaled performance and important contributions to physics in the next few years are anticipated.

    17. Elementary particle physics at the University of Florida. Annual report

      SciTech Connect

      Field, R.D.; Ramond, P.M.; Sikivie, P.

      1995-12-01

      This is the annual progress report of the University of Florida`s elementary particle physics group. The theoretical high energy physics group`s research covers a broad range of topics, including both theory and phenomenology. Present work of the experimental high energy physics group is directed toward the CLEO detector, with some effort going to B physics at Fermilab. The Axion Search project is participating in the operation of a large-scale axion detector at Lawrence Livermore National Laboratory, with the University of Florida taking responsibility for this experiment`s high-resolution spectrometer`s assembly, programming, and installation, and planning to take shifts during operation of the detector in FY96. The report also includes a continuation of the University`s three-year proposal to the United States Department of Energy to upgrade the University`s high-energy physics computing equipment and to continue student support, system manager/programmer support, and maintenance. Report includes lists of presentations and publications by members of the group.

    18. Marietta Blau: Pioneer of Photographic Nuclear Emulsions and Particle Physics

      NASA Astrophysics Data System (ADS)

      Sime, Ruth Lewin

      2013-03-01

      During the 1920s and 1930s, Viennese physicist Marietta Blau (1894-1970) pioneered the use of photographic methods for imaging high-energy nuclear particles and events. In 1937 she and Hertha Wambacher discovered "disintegration stars" - the tracks of massive nuclear disintegrations - in emulsions exposed to cosmic radiation. This discovery launched the field of particle physics, but Blau's contributions were underrecognized and she herself was nearly forgotten. I trace Blau's career at the Institut für Radiumforschung in Vienna and the causes of this "forgetting," including her forced emigration from Austria in 1938, the behavior of her colleagues in Vienna during and after the National Socialist period, and the flawed Nobel decision process that excluded her from a Nobel Prize.

    19. Wave-like variables of a classical particle and their connections to quantum mechanics

      NASA Astrophysics Data System (ADS)

      Yang, Chen

      2017-01-01

      In many texts, the transition from classical mechanics to quantum mechanics is achieved by substituting the action for the phase angle. The paper presents a different approach to show some connections between classical and quantum mechanics for a single particle for an audience at graduate and postgraduate levels. Firstly, it is shown that a wave equation of action can be derived under the free particle condition and the Legendre transform. The wave-like solutions of the action, Hamiltonian and momentum of the free particle are presented. Using the discrete approximation, the equation of motion of a single particle, in scalar potential field, is obtained in a similar form to Schrödinger’s equation. The rest of the paper discusses the propagation, superposition of the wave-like dynamic variables and their connections to quantum mechanics. The superposition of the variables of a particle is generally distinct from the superposition of classical waves (e.g. acoustics). The quantum superposition provides a self-consistent interpretation of the wave-like solutions of the variables. Connections between the classical and quantum relations for corresponding variables are observed from the one-to-one comparisons.

    20. A Particle Model Explaining Mass and Relativity in a Physical Way

      NASA Astrophysics Data System (ADS)

      Giese, Albrecht

      Physicists' understanding of relativity and the way it is handled is up to present days dominated by the interpretation of Albert Einstein, who related relativity to specific properties of space and time. The principal alternative to Einstein's interpretation is based on a concept proposed by Hendrik A. Lorentz, which uses knowledge of classical physics alone to explain relativistic phenomena. In this paper, we will show that on the one hand the Lorentz-based interpretation provides a simpler mathematical way of arriving at the known results for both Special and General Relativity. On the other hand, it is able to solve problems which have remained open to this day. Furthermore, a particle model will be presented, based on Lorentzian relativity and the quantum mechanical concept of Louis de Broglie, which explains the origin of mass without the use of the Higgs mechanism. It is based on the finiteness of the speed of light and provides classical results for particle properties which are currently only accessible through quantum mechanics.

    1. Computational particle physics for event generators and data analysis

      NASA Astrophysics Data System (ADS)

      Perret-Gallix, Denis

      2013-08-01

      High-energy physics data analysis relies heavily on the comparison between experimental and simulated data as stressed lately by the Higgs search at LHC and the recent identification of a Higgs-like new boson. The first link in the full simulation chain is the event generation both for background and for expected signals. Nowadays event generators are based on the automatic computation of matrix element or amplitude for each process of interest. Moreover, recent analysis techniques based on the matrix element likelihood method assign probabilities for every event to belong to any of a given set of possible processes. This method originally used for the top mass measurement, although computing intensive, has shown its efficiency at LHC to extract the new boson signal from the background. Serving both needs, the automatic calculation of matrix element is therefore more than ever of prime importance for particle physics. Initiated in the 80's, the techniques have matured for the lowest order calculations (tree-level), but become complex and CPU time consuming when higher order calculations involving loop diagrams are necessary like for QCD processes at LHC. New calculation techniques for next-to-leading order (NLO) have surfaced making possible the generation of processes with many final state particles (up to 6). If NLO calculations are in many cases under control, although not yet fully automatic, even higher precision calculations involving processes at 2-loops or more remain a big challenge. After a short introduction to particle physics and to the related theoretical framework, we will review some of the computing techniques that have been developed to make these calculations automatic. The main available packages and some of the most important applications for simulation and data analysis, in particular at LHC will also be summarized (see CCP2012 slides [1]).

    2. A Summer Research Experience in Particle Physics Using Skype

      NASA Astrophysics Data System (ADS)

      Johnston, Curran; Alexander, Steven; Mahmood, A. K.

      2012-10-01

      This last summer I did research in particle physics as part of a ``remote REU.'' This poster will describe that experience and the results of my project which was to experimentally verify the mass ranges of the Z' boson. Data from the LHC's Atlas detector was filtered by computers to select for likely Z boson decays; my work was in noting all instances of Z or Z' boson decays in one thousand events and their masses, separating the Z from Z' bosons, and generating histograms of the masses.

    3. Quantum simulations and many-body physics with light

      NASA Astrophysics Data System (ADS)

      Noh, Changsuk; Angelakis, Dimitris G.

      2017-01-01

      In this review we discuss the works in the area of quantum simulation and many-body physics with light, from the early proposals on equilibrium models to the more recent works in driven dissipative platforms. We start by describing the founding works on Jaynes-Cummings-Hubbard model and the corresponding photon-blockade induced Mott transitions and continue by discussing the proposals to simulate effective spin models and fractional quantum Hall states in coupled resonator arrays (CRAs). We also analyse the recent efforts to study out-of-equilibrium many-body effects using driven CRAs, including the predictions for photon fermionisation and crystallisation in driven rings of CRAs as well as other dynamical and transient phenomena. We try to summarise some of the relatively recent results predicting exotic phases such as super-solidity and Majorana like modes and then shift our attention to developments involving 1D nonlinear slow light setups. There the simulation of strongly correlated phases characterising Tonks-Girardeau gases, Luttinger liquids, and interacting relativistic fermionic models is described. We review the major theory results and also briefly outline recent developments in ongoing experimental efforts involving different platforms in circuit QED, photonic crystals and nanophotonic fibres interfaced with cold atoms.

    4. Quantum simulations and many-body physics with light.

      PubMed

      Noh, Changsuk; Angelakis, Dimitris G

      2017-01-01

      In this review we discuss the works in the area of quantum simulation and many-body physics with light, from the early proposals on equilibrium models to the more recent works in driven dissipative platforms. We start by describing the founding works on Jaynes-Cummings-Hubbard model and the corresponding photon-blockade induced Mott transitions and continue by discussing the proposals to simulate effective spin models and fractional quantum Hall states in coupled resonator arrays (CRAs). We also analyse the recent efforts to study out-of-equilibrium many-body effects using driven CRAs, including the predictions for photon fermionisation and crystallisation in driven rings of CRAs as well as other dynamical and transient phenomena. We try to summarise some of the relatively recent results predicting exotic phases such as super-solidity and Majorana like modes and then shift our attention to developments involving 1D nonlinear slow light setups. There the simulation of strongly correlated phases characterising Tonks-Girardeau gases, Luttinger liquids, and interacting relativistic fermionic models is described. We review the major theory results and also briefly outline recent developments in ongoing experimental efforts involving different platforms in circuit QED, photonic crystals and nanophotonic fibres interfaced with cold atoms.

    5. Applications of gaseous particle detectors in physics and medicine

      NASA Astrophysics Data System (ADS)

      Sauli, Fabio

      1995-08-01

      The multi-wire proportional chamber, introduced in 1967 by Georges Charpak (recipient of the 1992 Nobel prize for physics) allows to achieve high-rate, fully electronics detection and localization of ionizing radiation. The myriad of devices inspired by this initial work generated a revolution in the conception of detectors for elementary particle physics experiments; examples are the time projection chamber, the drift chamber, the micro-strip gas chamber. After a brief introduction on the basic operating principles of the device, I will describe several examples of application of advanced gas detectors in medicine and biology and analyze the operating characteristics that make the new devices attractive when confronted with classic detectors.

    6. Evolution of quantum field, particle content, and classicality in the three stage universe

      NASA Astrophysics Data System (ADS)

      Singh, Suprit; Modak, Sujoy Kumar; Padmanabhan, T.

      2013-12-01

      We study the evolution of a quantum scalar field in a toy universe which has three stages of evolution, viz., (i) an early (inflationary) de Sitter phase (ii) radiation-dominated phase and (iii) late-time (cosmological constant dominated) de Sitter phase. Using the Schrödinger picture, the scalar field equations are solved separately for the three stages and matched at the transition points. The boundary conditions are chosen so that field modes in the early de Sitter evolves from the Bunch-Davies vacuum state. We determine the (time-dependent) particle content of this quantum state for the entire evolution of the universe and describe the various features both numerically and analytically. We also describe the quantum to classical transition in terms of a classicality parameter which tracks the particle creation and its effect on phase space correlation of the quantum field.

    7. Transit time of a freely falling quantum particle in a background gravitational field

      NASA Astrophysics Data System (ADS)

      Davies, P. C. W.

      2004-12-01

      Using a model quantum clock, I evaluate an expression for the time of a non-relativistic quantum particle to transit a piecewise geodesic path in a background gravitational field with small spacetime curvature (gravity gradient), in the case in which the apparatus is in free fall. This calculation complements and extends an earlier one (Davies 2004) in which the apparatus is fixed to the surface of the Earth. The result confirms that, for particle velocities not too low, the quantum and classical transit times coincide, in conformity with the principle of equivalence. I also calculate the quantum corrections to the transit time when the de Broglie wavelengths are long enough to probe the spacetime curvature. The results are compared with the calculation of Chiao and Speliotopoulos (2003), who propose an experiment to measure the foregoing effects.

    8. Local State and Sector Theory in Local Quantum Physics

      NASA Astrophysics Data System (ADS)

      Ojima, Izumi; Okamura, Kazuya; Saigo, Hayato

      2016-06-01

      We define a new concept of local states in the framework of algebraic quantum field theory (AQFT). Local states are a natural generalization of states and give a clear vision of localization in the context of QFT. In terms of them, we can find a condition from which follows automatically the famous DHR selection criterion in DHR-DR theory. As a result, we can understand the condition as consequences of physically natural state preparations in vacuum backgrounds. Furthermore, a theory of orthogonal decomposition of completely positive (CP) maps is developed. It unifies a theory of orthogonal decomposition of states and order structure theory of CP maps. Using it, localized version of sectors is formulated, which gives sector theory for local states with respect to general reference representations.

    9. Electron-hole quantum physics in ZnO

      NASA Astrophysics Data System (ADS)

      Versteegh, M. A. M.

      2011-09-01

      This dissertation describes several new aspects of the quantum physics of electrons and holes in zinc oxide (ZnO), including a few possible applications. Zinc oxide is a II-VI semiconductor with a direct band gap in the ultraviolet. Experimental and theoretical studies have been performed, both on bulk ZnO and on ZnO nanowires. Chapter 2 presents a new technique for an ultrafast all-optical shutter, based on two-photon absorption in a ZnO crystal. This shutter can be used for luminescence experiments requiring extremely high time-resolution. Chapter 3 describes a time-resolved study on the electron-hole many-body effects in highly excited ZnO at room temperature, in particular band-filling, band-gap renormalization, and the disappearance of the exciton resonance due to screening. In Chapter 4, the quantum many-body theory developed and experimentally verified in Chapter 3, is used to explain laser action in ZnO nanowires, and compared with experimental results. In contrast to current opinion, the results indicate that excitons are not involved in the laser action. The measured emission wavelength, the laser threshold, and the spectral distance between the laser modes are shown to be excellently explained by our quantum many-body theory. Multiple scattering of light in a forest of nanowires can be employed to enhance light absorption in solar cells. Optimization of this technique requires better understanding of light diffusion in such a nanowire forest. In Chapter 5 we demonstrate a method, based on two-photon absorption, to directly measure the residence time of light in a nanowire forest, and we show that scanning electron microscope (SEM) images can be used to predict the photon mean free path. In Chapter 6 we present a new ultrafast all-optical transistor, consisting of a forest of ZnO nanowires. After excitation, laser action in this forest causes rapid recombination of the majority of the electrons and holes, limiting the amplification to 1.2 picoseconds only

    10. Quantum Phase Coherence in Mesoscopic Transport Devices with Two-Particle Interaction

      PubMed Central

      Wang, Zhimei; Guo, Xiaofang; Xue, Haibin; Xue, Naitao; Liang, J.-Q.

      2015-01-01

      In this paper we demonstrate a new type of quantum phase coherence (QPC), which is generated by the two-body interaction. This conclusion is based on quantum master equation analysis for the full counting statistics of electron transport through two parallel quantum-dots with antiparallel magnetic fluxes in order to eliminate the Aharonov-Bohm interference of either single-particle or non-interacting two-particle wave functions. The interacting two-particle QPC is realized by the flux-dependent oscillation of the zero-frequency cumulants including the shot noise and skewness with a characteristic period. The accurately quantized peaks of cumulant spectrum may have technical applications to probe the two-body Coulomb interaction. PMID:26255858

    11. Quantum work statistics of charged Dirac particles in time-dependent fields

      NASA Astrophysics Data System (ADS)

      Deffner, Sebastian; Saxena, Avadh

      The quantum Jarzynski equality is an important theorem of modern quantum thermodynamics. We show that the Jarzynski equality readily generalizes to relativistic quantum mechanics described by the Dirac equation. After establishing the conceptual framework we solve a pedagogical, yet experimentally relevant, system analytically. As a main result we obtain the exact quantum work distributions for charged particles traveling through a time-dependent vector potential evolving under Schrödinger as well as under Dirac dynamics, and for which the Jarzynski equality is verified. Special emphasis is put on the conceptual and technical subtleties arising from relativistic quantum mechanics. SD acknowledges financial support by the U.S. Department of Energy through a LANL Director's Funded Fellowship.

    12. [Investigations in dynamics of gauge theories in theoretical particle physics

      SciTech Connect

      Not Available

      1993-02-01

      The major theme of the theoretical physics research conducted under DOE support over the past several years has been within the rubric of the standard model, and concerned the interplay between symmetries and dynamics. The research was thus carried out mostly in the context of gauge field theories, and usually in the presence of chiral fermions. Dynamical symmetry breaking was examined both from the point of view of perturbation theory, as well as from non-perturbative techniques associated with certain characteristic features of specific theories. Among the topics of research were: the implications of abelian and non-abelian anomalies on the spectrum and possible dynamical symmetry breaking in any theory, topological and conformal properties of quantum fields in two and higher dimensions, the breaking of global chiral symmetries by vector-like gauge theories such as QCD, the phenomenological implications of a strongly interacting Higgs sector in the standard model, and the application of soliton ideas to the physics to be explored at the SSC.

    13. Semiclassical modeling of quantum-mechanical multiparticle systems using parallel particle-in-cell methods

      NASA Astrophysics Data System (ADS)

      Dauger, Dean Edward

      2001-08-01

      We are successful in building a code that models many particle dynamic quantum systems by combining a semiclassical approximation of Feynman path integrals with parallel computing techniques (particle-in-cell) and numerical methods developed for simulating plasmas, establishing this approach as a viable technique for multiparticle time-dependent quantum mechanics. Run on high-performance parallel computers, this code applies semiclassical methods to simulate the time evolution of wavefunctions of many particles. We describe the analytical derivation and computational implementation of these techniques in detail. We present a study to thoroughly demonstrate the code's fidelity to quantum mechanics, resulting in innovative visualization and analysis techniques. We introduce and exhibit a method to address fermion particle statistics. We present studies of two quantum-mechanical problems: a two-electron, one- dimensional atom, resulting in high-quality extractions of one- and two-electron eigenstates, and electrostatic quasi-modes due to quantum effects in a hot electron plasma, relevant for predictions about stellar evolution. We supply discussions of alternative derivations, alternative implementations of the derivations, and an exploration of their consequences. Source code is shown throughout this dissertation. Finally, we present an extensive discussion of applications and extrapolations of this work, with suggestions for future direction.

    14. PREFACE: 6th International Workshop on Pseudo-Hermitian Hamiltonians in Quantum Physics

      NASA Astrophysics Data System (ADS)

      Fring, Andreas; Jones, Hugh; Znojil, Miloslav

      2008-06-01

      Attempts to understand the quantum mechanics of non-Hermitian Hamiltonian systems can be traced back to the early days, one example being Heisenberg's endeavour to formulate a consistent model involving an indefinite metric. Over the years non-Hermitian Hamiltonians whose spectra were believed to be real have appeared from time to time in the literature, for instance in the study of strong interactions at high energies via Regge models, in condensed matter physics in the context of the XXZ-spin chain, in interacting boson models in nuclear physics, in integrable quantum field theories as Toda field theories with complex coupling constants, and also very recently in a field theoretical scenario in the quantization procedure of strings on an AdS5 x S5 background. Concrete experimental realizations of these types of systems in the form of optical lattices have been proposed in 2007. In the area of mathematical physics similar non-systematic results appeared sporadically over the years. However, intensive and more systematic investigation of these types of non- Hermitian Hamiltonians with real eigenvalue spectra only began about ten years ago, when the surprising discovery was made that a large class of one-particle systems perturbed by a simple non-Hermitian potential term possesses a real energy spectrum. Since then regular international workshops devoted to this theme have taken place. This special issue is centred around the 6th International Workshop on Pseudo-Hermitian Hamiltonians in Quantum Physics held in July 2007 at City University London. All the contributions contain significant new results or alternatively provide a survey of the state of the art of the subject or a critical assessment of the present understanding of the topic and a discussion of open problems. Original contributions from non-participants were also invited. Meanwhile many interesting results have been obtained and consensus has been reached on various central conceptual issues in the

    15. Landau-Level Mixing and Particle-Hole Symmetry Breaking for Spin Transitions in the Fractional Quantum Hall Effect.

      PubMed

      Zhang, Yuhe; Wójs, A; Jain, J K

      2016-09-09

      The spin transitions in the fractional quantum Hall effect provide a direct measure of the tiny energy differences between differently spin-polarized states and thereby serve as an extremely sensitive test of the quantitative accuracy of the theory of the fractional quantum Hall effect, and, in particular, of the role of Landau-level mixing in lifting the particle-hole symmetry. We report on an accurate quantitative study of this physics, evaluating the effect of Landau-level mixing in a nonperturbative manner using a fixed-phase diffusion Monte Carlo method. We find excellent agreement between our calculated critical Zeeman energies and the experimentally measured values. In particular, we find, as also do experiments, that the critical Zeeman energies for fractional quantum Hall states at filling factors ν=2-n/(2n±1) are significantly higher than those for ν=n/(2n±1), a quantitative signature of the lifting of particle-hole symmetry due to Landau-level mixing.

    16. Landau-Level Mixing and Particle-Hole Symmetry Breaking for Spin Transitions in the Fractional Quantum Hall Effect

      NASA Astrophysics Data System (ADS)

      Zhang, Yuhe; Wójs, A.; Jain, J. K.

      2016-09-01

      The spin transitions in the fractional quantum Hall effect provide a direct measure of the tiny energy differences between differently spin-polarized states and thereby serve as an extremely sensitive test of the quantitative accuracy of the theory of the fractional quantum Hall effect, and, in particular, of the role of Landau-level mixing in lifting the particle-hole symmetry. We report on an accurate quantitative study of this physics, evaluating the effect of Landau-level mixing in a nonperturbative manner using a fixed-phase diffusion Monte Carlo method. We find excellent agreement between our calculated critical Zeeman energies and the experimentally measured values. In particular, we find, as also do experiments, that the critical Zeeman energies for fractional quantum Hall states at filling factors ν =2 -n /(2 n ±1 ) are significantly higher than those for ν =n /(2 n ±1 ), a quantitative signature of the lifting of particle-hole symmetry due to Landau-level mixing.

    17. Modelling Systems of Classical/Quantum Identical Particles by Focusing on Algorithms

      ERIC Educational Resources Information Center

      Guastella, Ivan; Fazio, Claudio; Sperandeo-Mineo, Rosa Maria

      2012-01-01

      A procedure modelling ideal classical and quantum gases is discussed. The proposed approach is mainly based on the idea that modelling and algorithm analysis can provide a deeper understanding of particularly complex physical systems. Appropriate representations and physical models able to mimic possible pseudo-mechanisms of functioning and having…

    18. 'Who Thinks Abstractly?': Quantum Theory and the Architecture of Physical Concepts

      SciTech Connect

      Plotnitsky, Arkady

      2011-03-28

      Beginning with its introduction by W. Heisenberg, quantum mechanics was often seen as an overly abstract theory, mathematically and physically, vis-a-vis classical physics or relativity. This perception was amplified by the fact that, while the quantum-mechanical formalism provided effective predictive algorithms for the probabilistic predictions concerning quantum experiments, it appeared unable to describe, even by way idealization, quantum processes themselves in space and time, in the way classical mechanics or relativity did. The aim of the present paper is to reconsider the nature of mathematical and physical abstraction in modern physics by offering an analysis of the concept of ''physical fact'' and of the concept of 'physical concept', in part by following G. W. F. Hegel's and G. Deleuze's arguments concerning the nature of conceptual thinking. In classical physics, relativity, and quantum physics alike, I argue, physical concepts are defined by the following main features - 1) their multi-component multiplicity; 2) their essential relations to problems; 3) and the interactions between physical, mathematical, and philosophical components within each concept. It is the particular character of these interactions in quantum mechanics, as defined by its essentially predictive (rather than descriptive) nature, that distinguishes it from classical physics and relativity.

    19. ``Who Thinks Abstractly?'': Quantum Theory and the Architecture of Physical Concepts

      NASA Astrophysics Data System (ADS)

      Plotnitsky, Arkady

      2011-03-01

      Beginning with its introduction by W. Heisenberg, quantum mechanics was often seen as an overly abstract theory, mathematically and physically, vis-à-vis classical physics or relativity. This perception was amplified by the fact that, while the quantum-mechanical formalism provided effective predictive algorithms for the probabilistic predictions concerning quantum experiments, it appeared unable to describe, even by way idealization, quantum processes themselves in space and time, in the way classical mechanics or relativity did. The aim of the present paper is to reconsider the nature of mathematical and physical abstraction in modern physics by offering an analysis of the concept of "physical fact" and of the concept of "physical concept," in part by following G. W. F. Hegel's and G. Deleuze's arguments concerning the nature of conceptual thinking. In classical physics, relativity, and quantum physics alike, I argue, physical concepts are defined by the following main features—1) their multi-component multiplicity; 2) their essential relations to problems; 3) and the interactions between physical, mathematical, and philosophical components within each concept. It is the particular character of these interactions in quantum mechanics, as defined by its essentially predictive (rather than descriptive) nature, that distinguishes it from classical physics and relativity.

    20. Wave-Particle Duality and Uncertainty Principle: Phenomenographic Categories of Description of Tertiary Physics Students' Depictions

      ERIC Educational Resources Information Center

      Ayene, Mengesha; Kriek, Jeanne; Damtie, Baylie

      2011-01-01

      Quantum mechanics is often thought to be a difficult subject to understand, not only in the complexity of its mathematics but also in its conceptual foundation. In this paper we emphasize students' depictions of the uncertainty principle and wave-particle duality of quantum events, phenomena that could serve as a foundation in building an…

    1. Trends in integrated circuit design for particle physics experiments

      NASA Astrophysics Data System (ADS)

      Atkin, E. V.

      2017-01-01

      Integrated circuits are one of the key complex units available to designers of multichannel detector setups. A whole number of factors makes Application Specific Integrated Circuits (ASICs) valuable for Particle Physics and Astrophysics experiments. Among them the most important ones are: integration scale, low power dissipation, radiation tolerance. In order to make possible future experiments in the intensity, cosmic, and energy frontiers today ASICs should provide new level of functionality at a new set of constraints and trade-offs, like low-noise high-dynamic range amplification and pulse shaping, high-speed waveform sampling, low power digitization, fast digital data processing, serialization and data transmission. All integrated circuits, necessary for physical instrumentation, should be radiation tolerant at an earlier not reached level (hundreds of Mrad) of total ionizing dose and allow minute almost 3D assemblies. The paper is based on literary source analysis and presents an overview of the state of the art and trends in nowadays chip design, using partially own ASIC lab experience. That shows a next stage of ising micro- and nanoelectronics in physical instrumentation.

    2. Chemical physics: Quantum control of light-induced reactions

      NASA Astrophysics Data System (ADS)

      Chandler, David W.

      2016-07-01

      An investigation of how ultracold molecules are broken apart by light reveals surprising, previously unobserved quantum effects. The work opens up avenues of research in quantum optics. See Letter p.122

    3. Condensed-matter physics: Quantum mechanics in a spin

      NASA Astrophysics Data System (ADS)

      Balents, Leon

      2016-12-01

      Quantum spin liquids are exotic states of matter first predicted more than 40 years ago. An inorganic material has properties consistent with these predictions, revealing details about the nature of quantum matter. See Letter p.559

    4. Observing quantum nonlocality in the entanglement between modes of massive particles

      SciTech Connect

      Ashhab, S.; Maruyama, Koji

      2007-02-15

      We consider the question of whether it is possible to use the entanglement between spatially separated modes of massive particles to observe nonlocal quantum correlations. Mode entanglement can be obtained using a single particle, indicating that it requires careful consideration before concluding whether experimental observation--e.g., violation of Bell inequalities--is possible or not. In the simplest setups analogous to optics experiments, that observation is prohibited by fundamental conservation laws. However, we show that using auxiliary particles, mode entanglement can be converted into forms that allow the observation of quantum nonlocality. The probability of successful conversion depends on the nature and number of auxiliary particles used. In particular, we find that an auxiliary Bose-Einstein condensate allows the conversion arbitrarily many times with a small error that depends only on the initial state of the condensate.

    5. Four-Dimensional Spatial Nanometry of Single Particles in Living Cells Using Polarized Quantum Rods

      PubMed Central

      Watanabe, Tomonobu M.; Fujii, Fumihiko; Jin, Takashi; Umemoto, Eiji; Miyasaka, Masayuki; Fujita, Hideaki; Yanagida, Toshio

      2013-01-01

      Single particle tracking is widely used to study protein movement with high spatiotemporal resolution both in vitro and in cells. Quantum dots, which are semiconductor nanoparticles, have recently been employed in single particle tracking because of their intense and stable fluorescence. Although single particles inside cells have been tracked in three spatial dimensions (X, Y, Z), measurement of the angular orientation of a molecule being tracked would significantly enhance our understanding of the molecule’s function. In this study, we synthesized highly polarized, rod-shaped quantum dots (Qrods) and developed a coating method that optimizes the Qrods for biological imaging. We describe a Qrod-based single particle tracking technique that blends optical nanometry with nanomaterial science to simultaneously measure the three-dimensional and angular movements of molecules. Using Qrods, we spatially tracked a membrane receptor in living cells in four dimensions with precision close to the single-digit range in nanometers and degrees. PMID:23931303

    6. Particle physics and cosmology, Task C. Progress report, January 1992--April 1993

      SciTech Connect

      Turner, M.S.

      1993-05-01

      The research has spanned many topics at the boundary of particle physics and cosmology. The major focus has been in the general areas of inflationary cosmology, cosmological phase transitions, astrophysical constraints to particle physics theories, and dark matter/structure formation as it relates to particle physics. Some attention is given to axion physics. Narrative summaries of the research of the individual group members are given, followed by a list of publications.

    7. [Research in theoretical and experimental elementary particle physics. Final report

      SciTech Connect

      1998-11-01

      This report gives summaries of particle physics research conducted by different group members for Task A. A summary of work on the CLEO experiment and detector is included for Task B along with a list of CLEO publications. During the present grant period for Task C, the authors had responsibility for the design, assembly, and programming of the high-resolution spectrometer which looks for narrow peaks in the output of the cavity in the LLNL experiment. They successfully carried out this task. Velocity peaks are expected in the spectrum of dark matter axions on Earth. The computing proposal (Task S) is submitted in support of the High Energy Experiment (CLEO, Fermilab, CMS) and the Theory tasks.

    8. Superconducting Kinetic Inductance Detectors for astronomy and particle physics

      NASA Astrophysics Data System (ADS)

      Calvo, M.; Goupy, J.; D`Addabbo, A.; Benoit, A.; Bourrion, O.; Catalano, A.; Monfardini, A.

      2016-07-01

      Kinetic Inductance Detectors (KID) represent a novel detector technology based on superconducting resonators. Since their first demonstration in 2003, they have been rapidly developed and are today a strong candidate for present and future experiments in the different bands of the electromagnetic spectrum. This has been possible thanks to the unique features of such devices: in particular, they couple a very high sensitivity to their intrinsic suitability for frequency domain multiplexed readout, making the fabrication of large arrays of ultrasensitive detectors possible. There are many fields of application that can profit of such detectors. Here, we will briefly review the principle of operation of a KID, and give two sample applications, to mm-wave astronomy and to particle physics.

    9. A Complete Physical Germanium-on-Silicon Quantum Dot Self-Assembly Process

      PubMed Central

      Alkhatib, Amro; Nayfeh, Ammar

      2013-01-01

      Achieving quantum dot self-assembly at precise pre-defined locations is of vital interest. In this work, a novel physical method for producing germanium quantum dots on silicon using nanoindentation to pre-define nucleation sites is described. Self-assembly of ordered ~10 nm height germanium quantum dot arrays on silicon substrates is achieved. Due to the inherent simplicity and elegance of the proposed method, the results describe an attractive technique to manufacture semiconductor quantum dot structures for future quantum electronic and photonic applications. PMID:23807261

    10. FOREWORD: Corfu Summer Institute on Elementary Particle Physics (CORFU2005)

      NASA Astrophysics Data System (ADS)

      Anagnostopoulos, Konstantinos; Antoniadis, Ignatios; Fanourakis, George; Kehagias, Alexandros; Savoy-Navarro, Aurore; Wess, Julius; Zoupanos, George

      2006-12-01

      These are the Proceedings of the Corfu Summer Institute on Elementary Particle Physics (CORFU2005) (http://corfu2005.physics.uoi.gr), which took place in Corfu, Greece from 4 - 26 September 2005. The Corfu Summer Institute has a very long, interesting and successful history, some elements of which can be found in http://www.corfu-summer-institute.gr. In short, the Corfu Meeting started as a Summer School on Elementary Particle Physics (EPP) mostly for Greek graduate students in 1982 and has developed into a leading international Summer Institute in the field of EPP, both experimental and theoretical, providing in addition a very rich outreach programme to teachers and school students. The CORFU2005 Summer Institute on EPP, although based on the general format that has been developed and established in the Corfu Meetings during previous years, is characterized by the fact that it was a full realization of a new idea, which started experimentally in the previous two Corfu Meetings. The successful new ingredient was that three European Marie Curie Research Training Networks decided to hold their Workshops in Corfu during September 2005 and they managed to coordinate the educational part of their meetings to a huge Summer School called `The 8th Hellenic School on Elementary Particle Physics' (4 - 11 September). The European Networks which joined forces to materialize this project and the corresponding dates of their own Workshops are:

    11. The Third Generation as a Probe for New Physics: Experimental and Technological Approach (4 - 11 September)
    12. The Quest for Unification Theory Confronts Experiment (11 - 18 September)
    13. Constituents Fundamental Forces and Symmetries of the Universe (20 - 26 September)
    14. To these Workshops has been added a Satellite one called `Noncommutative Geometry in Field and String Theory', and some extra speakers have been invited to complement the full programme of CORFU2005, some of whom have integrated into the Workshop

    15. Classical Physics and the Bounds of Quantum Correlations.

      PubMed

      Frustaglia, Diego; Baltanás, José P; Velázquez-Ahumada, María C; Fernández-Prieto, Armando; Lujambio, Aintzane; Losada, Vicente; Freire, Manuel J; Cabello, Adán

      2016-06-24

      A unifying principle explaining the numerical bounds of quantum correlations remains elusive, despite the efforts devoted to identifying it. Here, we show that these bounds are indeed not exclusive to quantum theory: for any abstract correlation scenario with compatible measurements, models based on classical waves produce probability distributions indistinguishable from those of quantum theory and, therefore, share the same bounds. We demonstrate this finding by implementing classical microwaves that propagate along meter-size transmission-line circuits and reproduce the probabilities of three emblematic quantum experiments. Our results show that the "quantum" bounds would also occur in a classical universe without quanta. The implications of this observation are discussed.

    16. PREFACE: High Energy Particle Physics Workshop (HEPPW2015)

      NASA Astrophysics Data System (ADS)

      Cornell, Alan S.; Mellado, B.

      2015-10-01

      The motivation for this workshop began with the discovery of the Higgs boson three years ago, and the realisation that many problems remain in particle physics, such as why there is more matter than anti-matter, better determining the still poorly measured parameters of the strong force, explaining possible sources for dark matter, naturalness etc. While the newly discovered Higgs boson seems to be compatible with the Standard Model, current experimental accuracy is far from providing a definitive statement with regards to the nature of this new particle. There is a lot of room for physics beyond the Standard Model to emerge in the exploration of the Higgs boson. Recent measurements in high-energy heavy ion collisions at the LHC have shed light on the complex dynamics that govern high-density quark-gluon interactions. An array of results from the ALICE collaboration have been highlighted in a recent issue of CERN courier. The physics program of high-energy heavy ion collisions promises to further unveil the intricacies of high-density quark-gluon plasma physics. The great topicality of high energy physics research has also seen a rapid increase in the number of researchers in South Africa pursuing such studies, both experimentally through the ATLAS and ALICE colliders at CERN, and theoretically. Young researchers and graduate students largely populate these research groups, with little experience in presenting their work, and few support structures (to their knowledge) to share experiences with. Whilst many schools and workshops have sought to educate these students on the theories and tools they will need to pursue their research, few have provided them with a platform to present their work. As such, this workshop discussed the various projects being pursued by graduate students and young researchers in South Africa, enabling them to develop networks for future collaboration and discussion. The workshop took place at the iThemba Laboratories - North facility, in

    17. Quantum-behaved particle swarm optimization with collaborative attractors for nonlinear numerical problems

      NASA Astrophysics Data System (ADS)

      Liu, Tianyu; Jiao, Licheng; Ma, Wenping; Shang, Ronghua

      2017-03-01

      In this paper, an improved quantum-behaved particle swarm optimization (CL-QPSO), which adopts a new collaborative learning strategy to generate local attractors for particles, is proposed to solve nonlinear numerical problems. Local attractors, which directly determine the convergence behavior of particles, play an important role in quantum-behaved particle swarm optimization (QPSO). In order to get a promising and efficient local attractor for each particle, a collaborative learning strategy is introduced to generate local attractors in the proposed algorithm. Collaborative learning strategy consists of two operators, namely orthogonal operator and comparison operator. For each particle, orthogonal operator is used to discover the useful information that lies in its personal and global best positions, while comparison operator is used to enhance the particle's ability of jumping out of local optima. By using a probability parameter, the two operators cooperate with each other to generate local attractors for particles. A comprehensive comparison of CL-QPSO with some state-of-the-art evolutionary algorithms on nonlinear numeric optimization functions demonstrates the effectiveness of the proposed algorithm.

    18. Simple One-Dimensional Quantum-Mechanical Model for a Particle Attached to a Surface

      ERIC Educational Resources Information Center

      Fernandez, Francisco M.

      2010-01-01

      We present a simple one-dimensional quantum-mechanical model for a particle attached to a surface. It leads to the Schrodinger equation for a harmonic oscillator bounded on one side that we solve in terms of Weber functions and discuss the behaviour of the eigenvalues and eigenfunctions. We derive the virial theorem and other exact relationships…

    19. Absolutely continuous spectrum implies ballistic transport for quantum particles in a random potential on tree graphs

      NASA Astrophysics Data System (ADS)

      Aizenman, Michael; Warzel, Simone

      2012-09-01

      We discuss the dynamical implications of the recent proof that for a quantum particle in a random potential on a regular tree graph absolutely continuous (ac) spectrum occurs non-perturbatively through rare fluctuation-enabled resonances. The main result is spelled in the title.

    20. Absolutely continuous spectrum implies ballistic transport for quantum particles in a random potential on tree graphs

      SciTech Connect

      Aizenman, Michael; Warzel, Simone

      2012-09-15

      We discuss the dynamical implications of the recent proof that for a quantum particle in a random potential on a regular tree graph absolutely continuous (ac) spectrum occurs non-perturbatively through rare fluctuation-enabled resonances. The main result is spelled in the title.

    21. European Particle Physics Masterclasses Make Students into Scientists for a Day

      ERIC Educational Resources Information Center

      Johansson, K. E.; Kobel, M.; Hillebrandt, D.; Engeln, K.; Euler, M.

      2007-01-01

      In 2005 the European particle physics masterclasses attracted 3000 students from 18 European countries to visit one of 58 universities and education centres. The participants worked with data from real high energy particle collisions, learned about particle physics, and experienced research and education environments at European universities. In…

    22. [High energy particle physics at Purdue, 1990--1991]. [Dept. of Physics, Purdue Univ. , West Lafayette, Indiana

      SciTech Connect

      Gaidos, J.A.; Loeffler, F.J.; McIlwain, R.L.; Miller, D.H.; Palfrey, T.R.; Shibata, E.I.; Shipsey, I.P.

      1991-05-01

      Progress made in the experimental and theoretical high energy physics program is reviewed. The CLEO experiment, particle astrophysics, dynamical symmetry breaking in gauge theories, the Collider Detector at Fermilab, the TOPAZ Experiment, and elementary particle physics beyond the standard model are included.

    23. Review of lattice results concerning low-energy particle physics

      SciTech Connect

      Aoki, S.; Aoki, Y.; Bernard, C.; Blum, T.; Colangelo, G.; Della Morte, M.; Dürr, S.; El-Khadra, A. X.; Fukaya, H.; Horsley, R.; Jüttner, A.; Kaneko, T.; Laiho, J.; Lellouch, L.; Leutwyler, H.; Lubicz, V.; Lunghi, E.; Necco, S.; Onogi, T.; Pena, C.; Sachrajda, C. T.; Sharpe, S. R.; Simula, S.; Sommer, R.; Van de Water, R. S.; Vladikas, A.; Wenger, U.; Wittig, H.

      2014-09-01

      We review lattice results related to pion, kaon, D- and B-meson physics with the aim of making them easily accessible to the particle physics community. More specifically, we report on the determination of the light-quark masses, the form factor f+(0), arising in semileptonic K -> pi transition at zero momentum transfer, as well as the decay constant ratio fK/fpi of decay constants and its consequences for the CKM matrix elements Vus and Vud. Furthermore, we describe the results obtained on the lattice for some of the low-energy constants of SU(2)LxSU(2)R and SU(3)LxSU(3)R Chiral Perturbation Theory and review the determination of the BK parameter of neutral kaon mixing. The inclusion of heavy-quark quantities significantly expands the FLAG scope with respect to the previous review. Therefore, for this review, we focus on D- and B-meson decay constants, form factors, and mixing parameters, since these are most relevant for the determination of CKM matrix elements and the global CKM unitarity-triangle fit. In addition we review the status of lattice determinations of the strong coupling constant alpha_s.

    24. Review of lattice results concerning low-energy particle physics

      DOE PAGES

      Aoki, S.; Aoki, Y.; Bernard, C.; ...

      2014-09-01

      We review lattice results related to pion, kaon, D- and B-meson physics with the aim of making them easily accessible to the particle physics community. More specifically, we report on the determination of the light-quark masses, the form factor f+(0), arising in semileptonic K -> pi transition at zero momentum transfer, as well as the decay constant ratio fK/fpi of decay constants and its consequences for the CKM matrix elements Vus and Vud. Furthermore, we describe the results obtained on the lattice for some of the low-energy constants of SU(2)LxSU(2)R and SU(3)LxSU(3)R Chiral Perturbation Theory and review the determination ofmore » the BK parameter of neutral kaon mixing. The inclusion of heavy-quark quantities significantly expands the FLAG scope with respect to the previous review. Therefore, for this review, we focus on D- and B-meson decay constants, form factors, and mixing parameters, since these are most relevant for the determination of CKM matrix elements and the global CKM unitarity-triangle fit. In addition we review the status of lattice determinations of the strong coupling constant alpha_s.« less