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Sample records for particle physics quantum

  1. Counterfactual quantum-information transfer without transmitting any physical particles.

    PubMed

    Guo, Qi; Cheng, Liu-Yong; Chen, Li; Wang, Hong-Fu; Zhang, Shou

    2015-01-01

    We demonstrate quantum information can be transferred between two distant participants without any physical particles traveling between them. The key procedure of the counterfactual scheme is to entangle two nonlocal qubits with each other without interaction, so the scheme can also be used to generate nonlocal entanglement counterfactually. We here illustrate the scheme by using flying photon qubits and Rydberg atom qubits assisted by a mesoscopic atomic ensemble. Unlike the typical teleportation, the present scheme can transport an unknown qubit in a nondeterministic manner without prior entanglement sharing or classical communication between the two distant participants. PMID:25672936

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

    ScienceCinema

    None

    2011-10-06

    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. 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.

  4. Quantum Physics

    NASA Astrophysics Data System (ADS)

    Rae, Alastair

    2012-03-01

    Preface to the second edition; Preface to the first edition; 1. Quantum physics; 2. Which way are the photons pointing?; 3. What can be hidden in a pair of photons?; 4. Wonderful Copenhagen?; 5. Is it all in the mind?; 6. Many worlds; 7. Is it a matter of size?; 8. Backwards and forwards; 9. Only one way forward?; 10. Can we be consistent?; 11. Illusion or reality?; Further reading.

  5. 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)

  6. Self-Localized Quasi-Particle Excitation in Quantum Electrodynamics and Its Physical Interpretation

    NASA Astrophysics Data System (ADS)

    Feranchuk, Ilya D.; Feranchuk, Sergey I.

    2007-12-01

    The self-localized quasi-particle excitation of the electron-positron field (EPF) is found for the first time in the framework of a standard form of the quantum electrodynamics. This state is interpreted as the ''physical'' electron (positron) and it allows one to solve the following problems: i) to express the ''primary'' charge e0 and the mass m0 of the ''bare'' electron in terms of the observed values of e and m of the ''physical'' electron without any infinite parameters and by essentially nonperturbative way; ii) to consider μ-meson as another self-localized EPF state and to estimate the ratio mμ/m; iii) to prove that the self-localized state is Lorentz-invariant and its energy spectrum corresponds to the relativistic free particle with the observed mass m; iv) to show that the expansion in a power of the observed charge e << 1 corresponds to the strong coupling e! xpansion in a power of the ''primary'' charge e-10 ~ e when the interaction between the ``physical'' electron and the transverse electromagnetic field is considered by means of the perturbation theory and all terms of this series are free from the ultraviolet divergence.

  7. Particle Physics

    NASA Astrophysics Data System (ADS)

    Cooper, Necia Grant; West, Geoffrey B.

    1988-06-01

    Preface; Introduction; Part I. Theoretical Framework: 1. Scale and dimension - From animals to quarks Geoffrey B. West; 2. Particle physics and the standard model Stuart Raby, Richard C. Slansky and Geoffrey B. West; QCD on a Cray: the masses of elementary particles Gerald Guralnik, Tony Warnock and Charles Zemach; Lecture Notes - From simple field theories to the standard model; 3. Toward a unified theory: an essay on the role of supergravity in the search for unification Richard C. Slansky; 4. Supersymmetry at 100 GeV Stuart Raby; 5. The family problem T. Goldman and Michael Martin Nieto; Part II. Experimental Developments: 6. Experiments to test unification schemes Gary H. Sanders; 7. The march toward higher energies S. Peter Rosen; LAMPF II and the High-Intensity Frontier Henry A. Thiessen; The SSC - An engineering challenge Mahlon T. Wilson; 8. Science underground - the search for rare events L. M. Simmons, Jr; Part III. Personal Perspectives: 9. Quarks and quirks among friends Peter A. Carruthers, Stuart Raby, Richard C. Slansky, Geoffrey B. West and George Zweig; Index.

  8. 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)

  9. "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

  10. Quantum Physics in School.

    ERIC Educational Resources Information Center

    Lawrence, I.

    1996-01-01

    Discusses a teaching strategy for introducing quantum ideas into the school classroom using modern devices. Develops the concepts of quantization, wave-particle duality, nonlocality, and tunneling. (JRH)

  11. Quantum physics and language

    NASA Astrophysics Data System (ADS)

    Lévy-Leblond, Jean-Marc

    1988-07-01

    A novel theory, when it appears, cannot but use old words to label new concepts. In some cases, the extension in meaning thus conferred to standard terminology is natural enough so that the transfer may not lead to too many misunderstandings. Most often, however, and especially when the conceptual gap between the old and the new theory is a wide one, a casual transfer of términology may lead to epistemological and pedagogical difficulties. This situation has been and still is particularly serious in quantum theory. Here, the careless use of words taken from classical physics - such as quantum “mechanics”, “uncertainty”, etc. - , is compounded by the uncritical use of interpretative terms linked to a definite, if implicit, philosophical point of view - such as “complementarity”, “wave-particle duality”, “observables”, etc. While these words and the ideas they represent have played a major role in the birth of quantum physics more than half a century ago, they are no longer necessarily the best ones to be used today. It is not argued here that we should start afresh and create from scratch a supposedly adequate vocabulary for quantum physics. Abuse of language certainly is unavoidable in science as it is in any human communication; without it, language would not live and evolve. But, at the very least, let us recognize it for what it is, so that it does not add its troubles to already complicated issues. And in some definite instances, still, a willing effort to replace specially ambiguous words might be worthwhile.

  12. Statistical Physics of Particles

    NASA Astrophysics Data System (ADS)

    Kardar, Mehran

    2006-06-01

    Statistical physics has its origins in attempts to describe the thermal properties of matter in terms of its constituent particles, and has played a fundamental role in the development of quantum mechanics. Based on lectures for a course in statistical mechanics taught by Professor Kardar at Massachusetts Institute of Technology, this textbook introduces the central concepts and tools of statistical physics. It contains a chapter on probability and related issues such as the central limit theorem and information theory, and covers interacting particles, with an extensive description of the van der Waals equation and its derivation by mean field approximation. It also contains an integrated set of problems, with solutions to selected problems at the end of the book. It will be invaluable for graduate and advanced undergraduate courses in statistical physics. A complete set of solutions is available to lecturers on a password protected website at www.cambridge.org/9780521873420. Based on lecture notes from a course on Statistical Mechanics taught by the author at MIT Contains 89 exercises, with solutions to selected problems Contains chapters on probability and interacting particles Ideal for graduate courses in Statistical Mechanics

  13. TEACHING PHYSICS: Teaching particle physics

    NASA Astrophysics Data System (ADS)

    Hanley, Phil

    2000-09-01

    Particle physics attracts many students who hear of news from CERN or elsewhere in the media. This article examines which current A-level syllabuses include which bits of particle physics and surveys the many different types of resource available to teachers and students.

  14. 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)

  15. 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

  16. Faces of Quantum Physics

    NASA Astrophysics Data System (ADS)

    Haag, Rudolf

    We review conceptual structures met in quantum physics and note changes of basic concepts and language partly due to a maturing process in the 80 odd years since their first evocation by the founding fathers in Copenhagen, partly demanded or suggested by the passage from quantum mechanics to relativistic quantum field theory, local quantum physics and high energy experiments. It is in particular the concept of "observable" which lost its central role as a description of the measurement of some hypothetical property of a "physical system" under investigation and shifted to an auxiliary position as referring to a detector whose signals serve for the reconstruction of a history described in equations like (9.6), (9.7). The primary role is taken over by the notion of a (microscopic) event constituting the bridge to reality and to finer features of space-time.

  17. Finite groups and quantum physics

    SciTech Connect

    Kornyak, V. V.

    2013-02-15

    Concepts of quantum theory are considered from the constructive 'finite' point of view. The introduction of a continuum or other actual infinities in physics destroys constructiveness without any need for them in describing empirical observations. It is shown that quantum behavior is a natural consequence of symmetries of dynamical systems. The underlying reason is that it is impossible in principle to trace the identity of indistinguishable objects in their evolution-only information about invariant statements and values concerning such objects is available. General mathematical arguments indicate that any quantum dynamics is reducible to a sequence of permutations. Quantum phenomena, such as interference, arise in invariant subspaces of permutation representations of the symmetry group of a dynamical system. Observable quantities can be expressed in terms of permutation invariants. It is shown that nonconstructive number systems, such as complex numbers, are not needed for describing quantum phenomena. It is sufficient to employ cyclotomic numbers-a minimal extension of natural numbers that is appropriate for quantum mechanics. The use of finite groups in physics, which underlies the present approach, has an additional motivation. Numerous experiments and observations in the particle physics suggest the importance of finite groups of relatively small orders in some fundamental processes. The origin of these groups is unclear within the currently accepted theories-in particular, within the Standard Model.

  18. 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

  19. Advanced Level Physics Students' Conceptions of Quantum Physics.

    ERIC Educational Resources Information Center

    Mashhadi, Azam

    This study addresses questions about particle physics that focus on the nature of electrons. Speculations as to whether they are more like particles or waves or like neither illustrate the difficulties with which students are confronted when trying to incorporate the concepts of quantum physics into their overall conceptual framework. Such…

  20. Quantum entanglement and entropy in particle creation

    SciTech Connect

    Lin, S.-Y.; Chou, C.-H.; Hu, B. L.

    2010-04-15

    We investigate the basic theoretical issues in the quantum entanglement of particle pairs created from the vacuum in a time-dependent background field or spacetime. Similar to entropy generation from these processes which depends on the choice of physical variables and how certain information is coarse grained, entanglement dynamics hinges on the choice of measurable quantities and how the two parties are selected as well as the background dynamics of the field or spacetime. We discuss the conditions of separability of quantum states in particle creation processes and point out the differences in how the von Neumann entropy is used as a measure of entropy generation versus for entanglement dynamics. We show by an explicit construction that adoption of a different set of physical variables yields a different entanglement entropy. As an application of these theoretical considerations we show how the particle number and the quantum phase enter the entanglement dynamics in cosmological particle production.

  1. 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.

  2. 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.

  3. 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.

  4. Quantum cellular automata without particles

    NASA Astrophysics Data System (ADS)

    Meyer, David A.; Shakeel, Asif

    2016-01-01

    Quantum cellular automata (QCA) constitute space and time homogeneous discrete models for quantum field theories (QFTs). Although QFTs are defined without reference to particles, computations are done in terms of Feynman diagrams, which are explicitly interpreted in terms of interacting particles. Similarly, the easiest QCA to construct are quantum lattice gas automata (QLGA). A natural question then is, which QCA are not QLGA? Here we construct a nontrivial example of such a QCA; it provides a simple model in 1 +1 dimensions with no particle interpretation at the scale where the QCA dynamics are homogeneous.

  5. 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.

  6. 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.

  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. Research in particle physics

    NASA Astrophysics Data System (ADS)

    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.

  9. 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.

  10. Review of Particle Physics

    NASA Astrophysics Data System (ADS)

    Olive, K. A.; Particle Data Group

    2014-08-01

    The Review summarizes much of particle physics and cosmology. Using data from previous editions, plus 3,283 new measurements from 899 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 heavy neutrinos, supersymmetric and technicolor particles, 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 Supersymmetry, Extra Dimensions, Particle Detectors, Probability, and Statistics. Among the 112 reviews are many that are new or heavily revised including those on: Dark Energy, Higgs Boson Physics, Electroweak Model, Neutrino Cross Section Measurements, Monte Carlo Neutrino Generators, Top Quark, Dark Matter, Dynamical Electroweak Symmetry Breaking, Accelerator Physics of Colliders, High-Energy Collider Parameters, Big Bang Nucleosynthesis, Astrophysical Constants and Cosmological Parameters. All tables, listings, and reviews (and errata) are also available on the Particle Data Group website: http://pdg.lbl.gov. Contents Abstract, Contributors, Highlights and Table of ContentsAcrobat PDF (4.4 MB) IntroductionAcrobat PDF (595 KB) Particle Physics Summary Tables Gauge and Higgs bosonsAcrobat PDF (204 KB) LeptonsAcrobat PDF (167 KB) QuarksAcrobat PDF (115 KB) MesonsAcrobat PDF (976 KB) BaryonsAcrobat PDF (384 KB) Searches (Supersymmetry, Compositeness, etc.)Acrobat PDF (120 KB) Tests of conservation lawsAcrobat PDF (383 KB) Reviews, Tables, and Plots Detailed contents for this sectionAcrobat PDF (73 KB) Constants, Units, Atomic and Nuclear PropertiesAcrobat PDF (395 KB) Standard Model and Related TopicsAcrobat PDF (8.37 MB) Astrophysics and CosmologyAcrobat PDF (3.79 MB) Experimental Methods and CollidersAcrobat PDF (3.82 MB) Mathematical Tools of Statistics, Monte Carlo, Group Theory Acrobat

  11. 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.

  12. 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.

  13. 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.

  14. 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.

  15. The Physics of Quantum Computation

    NASA Astrophysics Data System (ADS)

    Falci, Giuseppe; Paladino, Elisabette

    2015-10-01

    Quantum Computation has emerged in the past decades as a consequence of down-scaling of electronic devices to the mesoscopic regime and of advances in the ability of controlling and measuring microscopic quantum systems. QC has many interdisciplinary aspects, ranging from physics and chemistry to mathematics and computer science. In these lecture notes we focus on physical hardware, present day challenges and future directions for design of quantum architectures.

  16. 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.

  17. 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.

  18. 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).

  19. 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).

  20. Quantum hoop conjecture: Black hole formation by particle collisions

    NASA Astrophysics Data System (ADS)

    Casadio, Roberto; Micu, Octavian; Scardigli, Fabio

    2014-05-01

    We address the issue of (quantum) black hole formation by particle collision in quantum physics. We start by constructing the horizon wave-function for quantum mechanical states representing two highly boosted non-interacting particles that collide in flat one-dimensional space. From this wave-function, we then derive a probability that the system becomes a black hole as a function of the initial momenta and spatial separation between the particles. This probability allows us to extend the hoop conjecture to quantum mechanics and estimate corrections to its classical counterpart.

  1. 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.

  2. 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…

  3. Blind Analysis in Particle Physics

    SciTech Connect

    Roodman, A

    2003-12-16

    A review of the blind analysis technique, as used in particle physics measurements, is presented. The history of blind analyses in physics is briefly discussed. Next the dangers of and the advantages of a blind analysis are described. Three distinct kinds of blind analysis in particle physics are presented in detail. Finally, the BABAR collaboration's experience with the blind analysis technique is discussed.

  4. 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.

  5. Research in elementary particle physics

    SciTech Connect

    Kirsch, L.E.; Schnitzer, H.J.; Bensinger, J.R.; Blocker, C.A.

    1992-01-01

    This report discusses research in the following areas of high energy physics: B meson mixing; CDF response to low energy jets; jet scaling behavior; search for pair produced leptoquarks at CDF; SSC program; quantum field theory; and neural networks. (LSP).

  6. 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.

  7. Quantum mechanics emerging from stochastic dynamics of virtual particles

    NASA Astrophysics Data System (ADS)

    Tsekov, Roumen

    2016-03-01

    It is shown how quantum mechanics emerges from the stochastic dynamics of force carriers. It is demonstrated that the Moyal equation corresponds to dynamic correlations between the real particle momentum and the virtual particle position, which are not present in classical mechanics. This new concept throws light on the physical meaning of quantum theory, showing that the Planck constant square is a second-second position-momentum cross-cumulant.

  8. Quantum Hamiltonian Physics with Supercomputers

    NASA Astrophysics Data System (ADS)

    Vary, James P.

    2014-06-01

    The vision of solving the nuclear many-body problem in a Hamiltonian framework with fundamental interactions tied to QCD via Chiral Perturbation Theory is gaining support. The goals are to preserve the predictive power of the underlying theory, to test fundamental symmetries with the nucleus as laboratory and to develop new understandings of the full range of complex quantum phenomena. Advances in theoretical frameworks (renormalization and many-body methods) as well as in computational resources (new algorithms and leadership-class parallel computers) signal a new generation of theory and simulations that will yield profound insights into the origins of nuclear shell structure, collective phenomena and complex reaction dynamics. Fundamental discovery opportunities also exist in such areas as physics beyond the Standard Model of Elementary Particles, the transition between hadronic and quark-gluon dominated dynamics in nuclei and signals that characterize dark matter. I will review some recent achievements and present ambitious consensus plans along with their challenges for a coming decade of research that will build new links between theory, simulations and experiment. Opportunities for graduate students to embark upon careers in the fast developing field of supercomputer simulations is also discussed.

  9. Higher-dimensional oscillations of quantum particles

    NASA Astrophysics Data System (ADS)

    Hedin, Eric

    2013-04-01

    A theoretical framework is developed in which elementary particles have a component of their wave function extending into higher spatial dimensions, based on an extension of the Schr"odinger equation to include 4^th and 5^th spatial components [E. R. Hedin, Physics Essays 25, 2 (2012)]. A higher-dimensional harmonic oscillator confining potential localizes particles into 3-d space (characterizing the ``brane tension'' which confines Standard Model particles to the sub-manifold). Several consistency checks of this model are: a match with the quantum phenomenon of ``zitterbewegung''; the predicted intrinsic spin angular momentum is of order h/2π; the magnetic moment of the electron is determined (with a gyromagnetic ratio of 2); the nuclear force ``hard core'' radius is accurately predicted; the ratio of quark masses (of the up and down quarks) is found to be consistent with QCD theory; and possible explanations of the Planck mass and Planck length. An application of higher-dimensional particle effects to the astrophysics of stars shows that radical physical inconsistencies are not evident. Finally, this model suggests a possible explanation of dark matter as the fractional probability manifestations of a ladder of the higher-dimensional symmetric excited states of ordinary particles.

  10. Particle Physics Masterclass

    ScienceCinema

    Helio Takai

    2010-01-08

    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,

  11. 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,

  12. 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.

  13. Quantum simulations of physics problems

    NASA Astrophysics Data System (ADS)

    Somma, Rolando D.; Ortiz, Gerardo; Knill, Emanuel H.; Gubernatis, James

    2003-08-01

    If a large Quantum Computer (QC) existed today, what type of physical problems could we efficiently simulate on it that we could not simulate on a classical Turing machine? In this paper we argue that a QC could solve some relevant physical "questions" more efficiently. The existence of one-to-one mappings between different algebras of observables or between different Hilbert spaces allow us to represent and imitate any physical system by any other one (e.g., a bosonic system by a spin-1/2 system). We explain how these mappings can be performed showing quantum networks useful for the efficient evaluation of some physical properties, such as correlation functions and energy spectra.

  14. Particle statistics affects quantum decay and Fano interference.

    PubMed

    Crespi, Andrea; Sansoni, Linda; Della Valle, Giuseppe; Ciamei, Alessio; Ramponi, Roberta; Sciarrino, Fabio; Mataloni, Paolo; Longhi, Stefano; Osellame, Roberto

    2015-03-01

    Quantum mechanical decay, Fano interference, and bound states with energy in the continuum are ubiquitous phenomena in different areas of physics. Here we experimentally demonstrate that particle statistics strongly affects quantum mechanical decay in a multiparticle system. By considering propagation of two-photon states in engineered photonic lattices, we simulate quantum decay of two noninteracting particles in a multilevel Fano-Anderson model. Remarkably, when the system sustains a bound state in the continuum, fractional decay is observed for bosonic particles, but not for fermionic ones. Complete decay in the fermionic case arises because of the Pauli exclusion principle, which forbids the bound state to be occupied by the two fermions. Our experiment indicates that particle statistics can tune many-body quantum decay from fractional to complete. PMID:25793783

  15. 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.

  16. 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.

  17. 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.

  18. Thermalization in Many-Particle Quantum Walks

    NASA Astrophysics Data System (ADS)

    Musumbu, Dibwe Pierrot; Przybylska, Maria; Maciejewski, Andrzej J.

    2016-03-01

    Many-particle quantum walks of particles obeying Bose statistics, moving on graphs of various topologies are introduced. A single coin tossing commands the conditional shift operation over the whole graph. Vertex particle densities, mean values of phase space variables, second order spatial correlations and counting statistics are evaluated and simulated. The evidence of universal dynamics is presented.

  19. Event Generators for Particle Physics

    NASA Astrophysics Data System (ADS)

    Matchev, Konstantin

    2014-03-01

    I will review recent progress in developing and automating the basic set of simulation tools in high energy particle physics, including programs which are capable of automatic implementation of new physics models and generating the corresponding Feynman rules, various matrix element calculators, and event generators producing both parton-level and fully hadronized/showerted Monte Carlo event samples. I will also discuss methods for speeding up the generation of new physics samples, which could be useful in the upcoming new physics searches at the LHC.

  20. 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.

  1. 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.

  2. 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

  3. Supersymmetry in Elementary Particle Physics

    SciTech Connect

    Peskin, Michael E.; /SLAC

    2008-02-05

    These lectures give a general introduction to supersymmetry, emphasizing its application to models of elementary particle physics at the 100 GeV energy scale. I discuss the following topics: the construction of supersymmetric Lagrangians with scalars, fermions, and gauge bosons, the structure and mass spectrum of the Minimal Supersymmetric Standard Model (MSSM), the measurement of the parameters of the MSSM at high-energy colliders, and the solutions that the MSSM gives to the problems of electroweak symmetry breaking and dark matter.

  4. Quantum physics and the beam splitter mystery

    NASA Astrophysics Data System (ADS)

    Hénault, François

    2015-09-01

    Optical lossless beam splitters are frequently encountered in fundamental physics experiments regarding the nature of light, including "which-way" determination or the EPR paradox and their measurement apparatus. Although they look as common optical components at first glance, their behaviour remains somewhat mysterious since they apparently exhibit stand-alone particle-like features, and then wave-like characteristics when inserted into a Mach-Zehnder interferometer. In this communication are examined and discussed some basic properties of these beamssplitters, both from a classical optics and quantum physics point of view. Herein the most evident convergences and contradictions are highlighted, and the results of a few emblematic experiments demonstrating photon existence are discussed. Alternative empirical models are also proposed in order to shed light on some remaining issues.

  5. Physical synthesis of quantum circuits using templates

    NASA Astrophysics Data System (ADS)

    Mirkhani, Zahra; Mohammadzadeh, Naser

    2016-06-01

    Similar to traditional CMOS circuits, quantum circuit design flow is divided into two main processes: logic synthesis and physical design. Addressing the limitations imposed on optimization of the quantum circuit metrics because of no information sharing between logic synthesis and physical design processes, the concept of "physical synthesis" was introduced for quantum circuit flow, and a few techniques were proposed for it. Following that concept, in this paper a new approach for physical synthesis inspired by template matching idea in quantum logic synthesis is proposed to improve the latency of quantum circuits. Experiments show that by using template matching as a physical synthesis approach, the latency of quantum circuits can be improved by more than 23.55 % on average.

  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. Quantum teleportation with identical particles

    NASA Astrophysics Data System (ADS)

    Marzolino, Ugo; Buchleitner, Andreas

    2015-03-01

    We study teleportation with identical massive particles. Indistinguishability imposes that the relevant degrees of freedom to be teleported are not particles, but rather addressable orthogonal modes. We discuss the performances of teleportation under the constraint of conservation of the total number of particles. The latter inevitably decreases the teleportation fidelity. Moreover, even though a phase reference, given by the coupling to a reservoir, circumvents the constraint, it does not restore perfect deterministic teleportation. The latter is only achievable with some special resource entangled states and when the number of particles tends to infinity. Interestingly, some of such states are the many-particle atomic coherent states and the ground state of cold atoms loaded into a double well potential, which are routinely prepared in experiments.

  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. Quantum Security for the Physical Layer

    SciTech Connect

    Humble, Travis S

    2013-01-01

    The physical layer describes how communication signals are encoded and transmitted across a channel. Physical security often requires either restricting access to the channel or performing periodic manual inspections. In this tutorial, we describe how the field of quantum communication offers new techniques for securing the physical layer. We describe the use of quantum seals as a unique way to test the integrity and authenticity of a communication channel and to provide security for the physical layer. We present the theoretical and physical underpinnings of quantum seals including the quantum optical encoding used at the transmitter and the test for non-locality used at the receiver. We describe how the envisioned quantum physical sublayer senses tampering and how coordination with higher protocol layers allow quantum seals to influence secure routing or tailor data management methods. We conclude by discussing challenges in the development of quantum seals, the overlap with existing quantum key distribution cryptographic services, and the relevance of a quantum physical sublayer to the future of communication security.

  10. 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.

  11. 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.

  12. 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.

  13. Quantum and classical dissipation of charged particles

    SciTech Connect

    Ibarra-Sierra, V.G.; Anzaldo-Meneses, A.; Cardoso, J.L.; Hernández-Saldaña, H.; Kunold, A.; Roa-Neri, J.A.E.

    2013-08-15

    A Hamiltonian approach is presented to study the two dimensional motion of damped electric charges in time dependent electromagnetic fields. The classical and the corresponding quantum mechanical problems are solved for particular cases using canonical transformations applied to Hamiltonians for a particle with variable mass. Green’s function is constructed and, from it, the motion of a Gaussian wave packet is studied in detail. -- Highlights: •Hamiltonian of a damped charged particle in time dependent electromagnetic fields. •Exact Green’s function of a charged particle in time dependent electromagnetic fields. •Time evolution of a Gaussian wave packet of a damped charged particle. •Classical and quantum dynamics of a damped electric charge.

  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. Non-accelerator particle physics

    SciTech Connect

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

    1991-09-01

    The goals of this research are the experimental testing of fundamental theories of physics such as grand unification 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 for grand unification magnetic monopoles and dark matter candidates and to study cosmic ray muons as well as low and high energy neutrinos: the {nu}IMB project, which seeks to refurbish and upgrade the IMB water Cerenkov detector to perform an improved proton decay search together with a long baseline reactor neutrino oscillation experiment using a kiloton liquid scintillator (the Perry experiment); 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. 21 refs., 19 figs., 6 tabs.

  16. 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.

  17. Quantum physics: Teleportation for two

    NASA Astrophysics Data System (ADS)

    Tittel, Wolfgang

    2015-02-01

    The 'no-cloning' theorem of quantum mechanics forbids the perfect copying of properties of photons or electrons. But quantum teleportation allows their flawless transfer -- now even for two properties simultaneously. See Letter p.516

  18. 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.

  19. Particle creation from the quantum stress tensor

    NASA Astrophysics Data System (ADS)

    Firouzjaee, Javad T.; Ellis, George F. R.

    2015-05-01

    Among the different methods to derive particle creation, finding the quantum stress tensor expectation value gives a covariant quantity which can be used for examining the backreaction issue. However this tensor also includes vacuum polarization in a way that depends on the vacuum chosen. Here we review different aspects of particle creation by looking at energy conservation and at the quantum stress tensor. We show that in the case of general spherically symmetric black holes that have a dynamical horizon, as occurs in a cosmological context, one cannot have pair creation on the horizon because this violates energy conservation. This confirms the results obtained in other ways in a previous paper [J. T. Firouzjaee and G. F. R. Ellis, Gen. Relativ. Gravit. 47, 6 (2015)]. Looking at the expectation value of the quantum stress tensor with three different definitions of the vacuum state, we study the nature of particle creation and vacuum polarization in black hole and cosmological models, and the associated stress-energy tensors. We show that the thermal temperature that is calculated from the particle flux given by the quantum stress tensor is compatible with the temperature determined by the affine null parameter approach. Finally, we show that in the spherically symmetric dynamic case, we can neglect the backscattering term and only consider the s-wave term near the future apparent horizon.

  20. 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.

  1. 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.

  2. 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…

  3. Quantum turbulence visualized by particle dynamics

    NASA Astrophysics Data System (ADS)

    La Mantia, M.; Skrbek, L.

    2014-07-01

    The Lagrangian dynamics of micrometer-sized solid particles of hydrogen and deuterium is investigated in thermal counterflow of superfluid He4 at length scales ℓexp straddling about two orders of magnitude across the average distance ℓ between quantized vortices by using the particle tracking velocimetry technique. The normalized probability distribution functions of the particle velocities and accelerations change from the shapes typical of quantum turbulence, characterized by power-law tails, at length scales ℓexp≲ℓ, to forms similar to those obtained in classical turbulent flows, at ℓexp≳ℓ, although the power-law behavior of the acceleration distribution tails is less clear than that observed for the particle velocities. Moreover, the acceleration distribution follows a nearly log-normal, classical-like shape, at ℓ ≲ℓexp≲Lint, where Lint denotes the integral length scale, providing thus, within the just defined inertial range, experimental evidence of the existence of classical-like, macroscopic vortical structures in thermal counterflow of superfluid He4, which is traditionally regarded as a quantum flow with no obvious classical analog. Additionally, we report our observations of the added mass effect in quantum turbulence and discuss them in the framework of a developed model of particle dynamics.

  4. Particle identification for beauty physics

    SciTech Connect

    Ludlam, T.

    1987-01-01

    We look briefly at the requirements for particle identification for possible beauty experiments at the Tevatron, both in the fixed target and the collider mode. Techniques presently in use in high energy physics experiments, and under development, should make sensitive experiments feasible. However, in all cases the present state of the art must be advanced to meet the necessary requirements for segmentation andor rate capability. The most fundamentally difficult challenges appear to be the efficient tagging of soft electrons (for the collider experiment) and the need to handle interaction rates up to /approximately/ 10/sub 9/ HZ in the fixed target mode. In both cases we can find ''in principle'' demonstrations that the requirements can be met. We have considered only the most basic prooperties of detectors, however, and the real answers will come from careful studies of details. 20 refs., 10 figs.

  5. 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.

  6. 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)

  7. 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.

  8. H-theorem in quantum physics.

    PubMed

    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

  9. 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.

  10. Localization and Entanglement in Relativistic Quantum Physics

    NASA Astrophysics Data System (ADS)

    Yngvason, Jakob

    These notes are a slightly expanded version of a lecture presented in February 2012 at the workshop "The Message of Quantum Science—Attempts Towards a Synthesis" held at the ZIF in Bielefeld. The participants were physicists with a wide range of different expertise and interests. The lecture was intended as a survey of a small selection of the insights into the structure of relativistic quantum physics that have accumulated through the efforts of many people over more than 50 years. (Including, among many others, R. Haag, H. Araki, D. Kastler, H.-J. Borchers, A. Wightman, R. Streater, B. Schroer, H. Reeh, S. Schlieder, S. Doplicher, J. Roberts, R. Jost, K. Hepp, J. Fröhlich, J. Glimm, A. Jaffe, J. Bisognano, E. Wichmann, D. Buchholz, K. Fredenhagen, R. Longo, D. Guido, R. Brunetti, J. Mund, S. Summers, R. Werner, H. Narnhofer, R. Verch, G. Lechner, ….) This contribution discusses some facts about relativistic quantum physics, most of which are quite familiar to practitioners of Algebraic Quantum Field Theory (AQFT) [Also known as Local Quantum Physics (Haag, Local quantum physics. Springer, Berlin, 1992).] but less well known outside this community. No claim of originality is made; the goal of this contribution is merely to present these facts in a simple and concise manner, focusing on the following issues: Explaining how quantum mechanics (QM) combined with (special) relativity, in particular an upper bound on the propagation velocity of effects, leads naturally to systems with an infinite number of degrees of freedom (relativistic quantum fields).

  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. 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

  13. Elementary particle physics---Experimental

    SciTech Connect

    Lord, J.J.; Burnett, T.H.; Wilkes, R.J.

    1990-09-20

    We are continuing a research program in high energy experimental particle physics and particle astrophysics. Studies of high energy hadronic interactions were performed using several techniques, in addition, a high energy leptoproduction experiment was continued at the Fermi National Accelerator Laboratory. 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. The data are being collected with ballon-borne emulsion chambers. The properties of nuclear interactions at these high energies will reveal whether new production mechanisms come into play due to the high nuclear densities and temperatures obtained. We carried out closely related studies of hadronic interactions in emulsions exposed to high energy accelerator beams. We are members of a large international collaboration which has exposed emulsion chamber detectors to beams of {sup 32}S and {sup 16}O with energy 60 and 200 GeV/n at CERN and 15 GeV/n at Brookhaven National Laboratory. The primary objectives of this program are to determine the existence and properties of the hypothesized quark-gluon phase of matter, and its possible relation to a variety of anomalous observations. Studies of leptoproduction processes at high energies involve two separate experiments, one using the Tevatron 500 GeV muon beam and the other exploring the >TeV regime. We are participants in Fermilab experiment E665 employing a comprehensive counter/streamer chamber detector system. During the past year we joined the DUMAND Collaboration, and have been assigned responsibility for development and construction of critical components for the deep undersea neutrino detector facility, to be deployed in 1991. In addition, we are making significant contributions to the design of the triggering system to be used.

  14. 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.

  15. Studies in theoretical particle physics

    NASA Astrophysics Data System (ADS)

    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.

  16. 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.

  17. Quantum simulations of relativistic quantum physics in circuit QED

    NASA Astrophysics Data System (ADS)

    Pedernales, J. S.; Di Candia, R.; Ballester, D.; Solano, E.

    2013-05-01

    We present a scheme for simulating relativistic quantum physics in circuit quantum electrodynamics. By using three classical microwave drives, we show that a superconducting qubit strongly coupled to a resonator field mode can be used to simulate the dynamics of the Dirac equation and Klein paradox in all regimes. Using the same setup we also propose the implementation of the Foldy-Wouthuysen canonical transformation, after which the time derivative of the position operator becomes a constant of the motion.

  18. 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.

  19. Computer Visualization of Many-Particle Quantum Dynamics

    NASA Astrophysics Data System (ADS)

    Ozhigov, A. Y.

    2009-03-01

    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.

  20. 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

  1. 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.

  2. Studies in Elementary Particle Physics

    NASA Astrophysics Data System (ADS)

    Appell, David Allen

    Three studies in elementary particle physics are presented. In the first, titled "Jets as a probe of quark -gluon plasmas", we investigate the propagation of jets through a quark-gluon plasma. The transverse-momentum imbalance of a jet pair is shown to be sensitive to multiple scattering off the constituents of the plasma for expected values of the plasma temperature and size. This raises the possibility that such transverse-momentum imbalance could be used as a probe of a quark-gluon plasma produced by partonic interactions in ultrarelativistic nucleus-nucleus collisions. The second topic considered is "Soft gluon effects and the normalization of the Drell-Yan cross section." There we analyze the sensitivity of the inclusive Drell -Yan cross section to soft gluon effects, using a previously developed summation procedure which includes nonleading logarithmic effects. By varying an infrared cutoff in gluon energies, we study the importance of soft, but still perturbative, gluons to the normalization of the cross section or, equivalently, the "K-factor." The result is strongly dependent on the kinematic range being considered, as well as on the parton distributions of the incoming hadrons. Finally, in "Problems of dimensional reduction and inflationary cosmology", we discuss various aspects of the relationship between Kaluza-Klein theories and cosmology, with particular emphasis on the process of dimensional reduction. Some features of higher-dimensional Friedman -Robertson-Walker-type universes are considered, such as the compatibility of the Einstein equations, their connection with the inflationary scenarios, and their consequences for the critical density of the observable universe. The role of the Casimir effect as a possible mechanism for dimensional compactification is noted, and the absence of the Casimir effect for supersymmetric theories is noted. Various subtleties of the Casimir effect make it difficult to decide at this point whether the Casimir effect

  3. 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…

  4. 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)

  5. 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…

  6. Quantum Mesoscopic Physics of Electrons and Photons

    NASA Astrophysics Data System (ADS)

    Akkermans, Eric

    2013-03-01

    We first review basic notions of coherent quantum transport at the mesoscopic scale for both electronic and photonic systems. We then show that successful descriptions developed for coherent electronic transport (e.g. weak localization and UCF) and thermodynamics (persistent currents), noise and full counting statistics can be extended and applied to the study of Quantum Electrodynamics of quantum conductors and of quantum optics based on photons emitted by such conductors. In this context, we discuss the two following specific problems : (1) Ramsey fringes and time domain interference for particle creation form a quantum vacuum with a specific application to dynamical Coulomb blockade. In that setup, the current noise of a coherent conductor is biased by two successive voltage pulses. An interference pattern between photon assisted processes is observed which is explained by the contribution of several processes to the probability to emit photons after each pulse. Recent experiments in this context will be discussed. (2) Quantum emitter coupled to a fractal environment. A new and unexpected type of oscillatory structures for the probability of spontaneous emission has been obtained which results from the fractal nature of the quantum vacuum. When applied to the case of a tunnel junction as a quantum emitter of photons, the same oscillatory structure arises for the conductance of the tunnel junction. This work was supported by the Israel Science Foundation Grant No.924/09

  7. Beyond relativity and quantum mechanics: space physics

    NASA Astrophysics Data System (ADS)

    Lindner, Henry H.

    2011-09-01

    Albert Einstein imposed an observer-based epistemology upon physics. Relativity and Quantum Mechanics limit physics to describing and modeling the observer's sensations and measurements. Their "underlying reality" consists only of ideas that serve to model the observer's experience. These positivistic models cannot be used to form physical theories of Cosmic phenomena. To do this, we must again remove the observer from the center of physics. When we relate motion to Cosmic space instead of to observers and we attempt to explain the causes of Cosmic phenomena, we are forced to admit that Cosmic space is a substance. We need a new physics of space. We can begin by replacing Relativity with a modified Lorentzian-Newtonian model of spatial flow, and Quantum Mechanics with a wave-based theory of light and electrons. Space physics will require the reinterpretation of all known phenomena, concepts, and mathematical models.

  8. Quantum dynamics and topological excitations in interacting dipolar particles

    NASA Astrophysics Data System (ADS)

    Rey, Ana

    2016-05-01

    Dipole-dipole interactions, long-range and anisotropic interactions that arise due to the virtual exchange of photons, are of fundamental importance in optical physics, and are enabling a range of new quantum technologies including quantum networks and optical lattice atomic clocks. In this talk I will first discuss how arrays of dipolar particles with a simple J = 0- J = 1 internal level structure can naturally host topological and chiral excitations including Weyl quasi-particles. Weyl fermions were first predicted to exist in the context of high energy physics but only recently have been observed in solid state systems. I will discuss a proposal of using Mott insulators of Sr atoms to observe and probe the Weyl excitation spectrum and its non-trivial chirality. Finally I will report on a recent experiment done at JILA which validates the underlying microscopic model that predicts the existence of these excitations. The experiment measured the collective emission from a coherently driven gas of ultracold 88 Sr atoms and observed a highly directional and anisotropic emission intensity and a substantial broadening of the atomic spectral lines. All of the measurements are well reproduced by the theoretical model. These investigations open the door for the exploration of novel quantum many-body systems involving strongly interacting atoms and photons, and are useful guides for further developments of optical atomic clocks and other applications involving dense atomic ensembles. AFOSR, MURI-AFOSR, ARO,NSF-PHY-1521080, JILA-NSF-PFC-1125844.

  9. 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

  10. Preparation and measurement in quantum physics

    NASA Astrophysics Data System (ADS)

    Park, James L.; Band, William

    1992-05-01

    To honor Henry Margenau on the occasion of his 90th birthday, we attempt in this essay to integrate certain aspects of the physics, philosophy, and pedagogy of quantum mechanics in a manner very much inspired by Margenau's idealist scientific epistemology. Over half a century ago, Margenau was perhaps the first philosopher of science to recognize and elaborate upon the essential distinction between the preparation of a quantum state and the measurement of an observable associated with a system in that state; yet in contemporary quantum texts that distinction rarely receives adequate emphasis even though, as we demonstrate, it may be explicated through a series of simple illustrations.

  11. 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. PMID:24482329

  12. Thermal equilibrium of two quantum Brownian particles

    SciTech Connect

    Valente, D. M.; Caldeira, A. O.

    2010-01-15

    The influence of the environment in the thermal equilibrium properties of a bipartite continuous variable quantum system is studied. The problem is treated within a system-plus-reservoir approach. The considered model reproduces the Brownian motion when the two particles are isolated and induces an effective interaction between them, depending on the choice of the spectral function of the bath. The coupling between the system and the environment guarantees the translational invariance of the system in the absence of an external potential. The entanglement between the particles is measured by the logarithmic negativity, which is shown to monotonically decrease with the increase of the temperature. A range of finite temperatures is found in which entanglement is still induced by the reservoir.

  13. Two Dimensional Particle-In-Cell Code for Simulation of Quantum Plasmas

    NASA Astrophysics Data System (ADS)

    Decyk, V. K.; Tonge, J.; Dauger, D. E.

    2002-11-01

    We have developed a two dimensional code for simulating quantum plasmas (1). This unique code propagates many quantum particles forward in time self-consistently using the semi-classical approximation. Because of this it can model the statistical properties of interacting quantum particles. We are currently testing this code using small numbers of particles with model problems which we can use to verify the accuracy of the code. The goal is to model from first principles the statistical properties of plasmas where quantum mechanics plays a role such as hot high density plasmas found in stellar interiors (2). (1) D. Dauger, Semiclassical Modeling of Quantum-Mechanical Multiparticle Systems using Parallel Particle-In-Cell Methods, PHD Thesis (2) M. Opher et. al. , Nuclear reaction rates and energy in stellar plasmas: The effect of highly damped modes, Physics of Plasma, 8, No. 5, p. 2454 Sponsored by NSF

  14. [Elementary particle physics. Annual report

    SciTech Connect

    Izen, J.M.; Lou, X.

    1998-12-31

    The BABAR construction phase is ending and first data is expected during May, 1999. During construction, UTD has developed analysis framework software, contributed to the BABAR Physics Book, assembled a first rate computing facility, and pioneered Internet-based video techniques for the collaboration. The authors are now defining the physics goals, and are participating in the formation physics analysis groups. They are starting to use their computing facility for BABAR production jobs.

  15. 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.

  16. Frontiers of particle beam physics

    SciTech Connect

    Sessler, A.M.

    1989-11-01

    First, a review is given of various highly-developed techniques for particle handling which are, nevertheless, being vigorously advanced at the present time. These include soft superconductor radio frequency cavities, hard superconductor magnets, cooling rings for ions and anti-protons, and damping rings for electrons. Second, attention is focused upon novel devices for particle generation, acceleration, and focusing. These include relativistic klystrons and free electron laser power sources, binary power multipliers, photocathodes, switched-power linacs, plasma beat-wave accelerators, plasma wake-field accelerators, plasma lenses, plasma adiabatic focusers and plasma compensators. 12 refs.

  17. Medium energy elementary particle physics

    SciTech Connect

    Not Available

    1991-01-01

    This report discusses the following topics: muon beam development at LAMPF; muon physics; a new precision measurement of the muon g-2 value; measurement of the spin-dependent structure functions of the neutron and proton; and meson factories. (LSP)

  18. Research in elementary particle physics

    NASA Astrophysics Data System (ADS)

    Kirsch, L. E.; Schnitzer, H. J.

    Research in theoretical and experimental properties of elementary particles is described. This includes measurements made at the multiparticle spectrometer facility at Brookhaven, studies of baryonium production, inclusive hyperon production, and E(0) production. Theoretical work included extended field theories, subconstituent models, finite temperature quatum chromodynamics, grad unified theories, and calculational techniques in gauge theories.

  19. 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

  20. 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.…

  1. Quantum mechanics of lattice gas automata: One-particle plane waves and potentials

    SciTech Connect

    Meyer, D.A.

    1997-05-01

    Classical lattice gas automata effectively simulate physical processes, such as diffusion and fluid flow (in certain parameter regimes), despite their simplicity at the microscale. Motivated by current interest in quantum computation we recently defined {ital quantum} lattice gas automata; in this paper we initiate a project to analyze which physical processes these models can effectively simulate. Studying the single particle sector of a one-dimensional quantum lattice gas we find discrete analogs of plane waves and wave packets, and then investigate their behavior in the presence of inhomogeneous potentials. {copyright} {ital 1997} {ital The American Physical Society}

  2. Introduction to Statistical Issues in Particle Physics

    NASA Astrophysics Data System (ADS)

    Barlow, Roger

    An account is given of the methods of working of Experimental High Energy Particle Physics, from the viewpoint of statisticians and others unfamiliar with the field. Current statistical problems, techniques, and hot topics are introduced and discussed.

  3. The Negative Binomial Distribution in Quantum Physics

    NASA Astrophysics Data System (ADS)

    Söderholm, Jonas; Inoue, Shuichiro

    2009-06-01

    We give examples of situations where the negative binomial distribution has appeared in quantum physics since its debut in the work of Planck. Several of its properties are reviewed, and Mandel's Q-parameter is shown to play an interesting role. The photon-pair distributions of squeezed vacuum and squeezed single-photon states are identified as negative binomial.

  4. Beams for the Intensity Frontier of Particle Physics

    NASA Astrophysics Data System (ADS)

    Tschirhart, Robert S.

    2014-02-01

    Advances in high intensity beams have driven particle physics forward since the inception of the field. State-of-the-art and next generation high intensity beams will drive experiments searching for ultrarare processes sensitive through quantum corrections to new particle states far beyond the reach of direct production in foreseeable beam colliders. The recent discovery of the ultrarare B meson decay Bs → μμ, with a branching fraction of 3 × 10-9 for example, has set stringent limits on new physics within direct reach of the Large Hadron Collider. Today, even in the context of the Higgs boson discovery, observation of finite neutrino masses is the only laboratory evidence of physics beyond the Standard Model of particle physics. The tiny mass scale of neutrinos may foretell and one day expose physics that connects quarks and leptons together at the "grand unification" scale and may be the portal through which our world came to the matter-dominated state so different from conditions we expect in the early universe. Here we describe next generation neutrino and rare processes experiments that will deeply probe these and other questions central to the field of particle physics.

  5. 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

  6. 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.

  7. A synthetic approach to the transfer matrix method in classical and quantum physics

    NASA Astrophysics Data System (ADS)

    Pujol, O.; Pérez, J. P.

    2007-07-01

    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 would benefit by using the abcd-matrix which in addition is easy to implement on a personal computer.

  8. 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?

  9. 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

  10. Research in Theoretical Particle Physics

    SciTech Connect

    Ralston, John P.

    2013-07-28

    This document is the final report on activity of the University of Kansas theory group supported under DOE Grant Number DE-FG02-04ER14308, ending April 30, 3013. The report covers the most recent three year period period May 1, 2010-April 30, 2013. Faculty supported by the grant during the period were Danny Marfatia (co-I), Douglas McKay (emeritus) and John Ralston (PI). The group's research topics and accomplishments covered numerous different topics subsumed under the {\\it the Energy Frontier, the Intensity Frontier}, and {\\it the Cosmic Frontier}. Many theoretical and experimental results related to the Standard Model and models of new physics were published during the reporting period. The group's research emphasis has been on challenging and confronting {\\it Anything that is Observable} about the physical Universe.

  11. 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.

  12. 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.

  13. Quantum supremacy of many-particle thermal machines

    NASA Astrophysics Data System (ADS)

    Jaramillo, J.; Beau, M.; del Campo, A.

    2016-07-01

    While the emergent field of quantum thermodynamics has the potential to impact energy science, the performance of thermal machines is often classical. We ask whether quantum effects can boost the performance of a thermal machine to reach quantum supremacy, i.e., surpassing both the efficiency and power achieved in classical thermodynamics. To this end, we introduce a nonadiabatic quantum heat engine operating an Otto cycle with a many-particle working medium, consisting of an interacting Bose gas confined in a time-dependent harmonic trap. It is shown that thanks to the interplay of nonadiabatic and many-particle quantum effects, this thermal machine can outperform an ensemble of single-particle heat engines with same resources, demonstrating the quantum supremacy of many-particle thermal machines.

  14. Quantum particles from coarse grained classical probabilities in phase space

    SciTech Connect

    Wetterich, C.

    2010-07-15

    Quantum particles can be obtained from a classical probability distribution in phase space by a suitable coarse graining, whereby simultaneous classical information about position and momentum can be lost. For a suitable time evolution of the classical probabilities and choice of observables all features of a quantum particle in a potential follow from classical statistics. This includes interference, tunneling and the uncertainty relation.

  15. Counting statistics of many-particle quantum walks

    SciTech Connect

    Mayer, Klaus; Tichy, Malte C.; Buchleitner, Andreas; Mintert, Florian; Konrad, Thomas

    2011-06-15

    We study quantum walks of many noninteracting particles on a beam splitter array as a paradigmatic testing ground for the competition of single- and many-particle interference in a multimode system. We derive a general expression for multimode particle-number correlation functions, valid for bosons and fermions, and infer pronounced signatures of many-particle interferences in the counting statistics.

  16. 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

  17. Discrimination of physical states in quantum systems

    NASA Astrophysics Data System (ADS)

    Shingu-Yano, Mayumi; Shibata, Fumiaki

    2001-04-01

    Quantum mechanical relaxation and decoherence processes are studied from a view point of discrimination problem of physical states. This is based on an information statistical mechanical method, where concept of a probability density and an entropy is to be generalized. We use a quasi-probability density of Q-function (Husimi function) and the corresponding entropy (Wehrl-Lieb entropy) and apply the method to a Brownian motion of an oscillator and a non-linear spin relaxation process. Our main concern lies in obtaining a discrimination probability Pd as a function of time and temperature. Quantum mechanical fluctuation causes profound effects than the thermal fluctuation.

  18. Master Equation for a Quantum Particle in a Gas

    SciTech Connect

    Hornberger, Klaus

    2006-08-11

    The equation for the quantum motion of a Brownian particle in a gaseous environment is derived by means of S-matrix theory. This quantum version of the linear Boltzmann equation accounts nonperturbatively for the quantum effects of the scattering dynamics and describes decoherence and dissipation in a unified framework. As a completely positive master equation it incorporates both the known equation for an infinitely massive Brownian particle and the classical linear Boltzmann equation as limiting cases.

  19. 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.

  20. 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.

    1. High Intensity Particle Physics at PW-class laser facilities

      NASA Astrophysics Data System (ADS)

      Bulanov, Stepan; Schroeder, Carl; Esarey, Eric; Esirkepov, Timur; Kando, Masaki; Rosanov, Nikolay; Korn, Georg; Bulanov, Sergey V.; Leemans, Wim P.

      2015-11-01

      The processes typical for high intensity particle physics, i.e., the interactions of charged particles with strong electromagnetic fields, have attracted considerable interest recently. Some of these processes, previously believed to be of theoretical interest only, are now becoming experimentally accessible. High intensity electromagnetic (EM) fields significantly modify the interactions of particles and EM fields, giving rise to the phenomena that are not encountered either in classical or perturbative quantum theory of these interactions. One of such phenomena is the radiation reaction, which radically influences the electron motion in an electromagnetic standing wave formed by two super-intense counter-propagating laser pulses. Depending on the laser intensity and wavelength, either classical or quantum mode of radiation reaction prevail, or both are strong. When radiation reaction dominates, electron motion evolves to limit cycles and strange attractors. This creates a new framework for high energy physics experiments on an interaction of energetic charged particle beams and colliding super-intense laser pulses. Work supported by U.S. DOE under Contract No. DE-AC02-05CH11231.

    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. 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).

    4. 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).

    5. 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.

    6. 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.

    7. 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

    8. 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. PMID:22984664

    9. Cosmology, astrophysics and elementary particle physics

      NASA Astrophysics Data System (ADS)

      Tayler, R. J.

      1980-03-01

      The physics of the early universe are studied and the role of new particles such as heavy leptons, neutrinos and quarks and possible relationship of the net baryon number of the universe to unified models of elementary particle physics are discussed. Consideration is given to the role of neutrinos in stellar evolution, particularly in the explosion of supernovae and in the cooling of neutron stars. Black holes are discussed in connection with Hawking's discovery that low-mass black holes can emit a thermal distribution of particles which could be of cosmological or astrophysical importance. Finally, the evidence that the laws of physics are unchanging is examined, and it is concluded that there is no clear case in favor of change.

    10. 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.

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

      NASA Astrophysics Data System (ADS)

      Beggi, Andrea; Buscemi, Fabrizio; Bordone, Paolo

      2016-06-01

      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.

    12. Quantum Gravity Corrections to the Tunneling Radiation of Scalar Particles

      NASA Astrophysics Data System (ADS)

      Wang, Peng; Yang, Haitang; Ying, Shuxuan

      2016-05-01

      The original derivation of Hawking radiation shows the complete evaporation of black holes. However, theories of quantum gravity predict the existence of the minimal observable length. In this paper, we investigate the tunneling radiation of the scalar particles by introducing the quantum gravity effects influenced by the generalized uncertainty principle. The Hawking temperatures are not only determined by the properties of the black holes, but also affected by the quantum numbers of the emitted particles. The quantum gravity corrections slow down the increase of the temperatures. The remnants are found during the evaporation.

    13. PHYSICAL FOUNDATIONS OF QUANTUM ELECTRONICS: The distribution function and fluctuations of the number of particles in an ideal Bose gas confined by a trap

      NASA Astrophysics Data System (ADS)

      Alekseev, Vladimir A.

      2001-01-01

      The distribution function ω0(n0) of the number n0 of particles in the condensate of an ideal Bose gas confined by a trap is found. It is shown that at the temperature above the critical one (T > Tc) this function has the usual form ω0(n0) =(1 — eμ)eμno, where μ is the chemical potential in the temperature units. For T < Tc, this distribution changes almost in a jump to a Gaussian distribution, which depends on the trap potential only parametrically. The centre of this function shifts to larger values of n0 with decreasing temperature and its width tends to zero, which corresponds to the suppression of fluctuations.

    14. Coherent States of Quantum Free Particle on the Spherical Space

      NASA Astrophysics Data System (ADS)

      Dehdashti, Shahram; Roknizadeh, Rasoul; Mahdifar, Ali; Chen, Hongsheng

      2016-01-01

      In this paper, we study the quantum free particle on the spherical space by applying da costa approach for quantum particle on the curved space. We obtain the discrete energy eigenvalues and associated normalized eigenfunctions of the free particle on the sphere. In addition, we introduce the Gazeau-Klauder coherent states of free particle on the sphere. Then, the Gaussian coherent states is defined, which is used to describe the localized particle on the spherical space. Finally, we study the relation between the f-deformed coherent states and Gazeau-Klauder ones for this system.

    15. Particle physics with the LHC data

      SciTech Connect

      Hagiwara, Kaoru

      2012-07-27

      In this talk, I give reasons why we regard GUT as a part of the Standard Model of Elementary Particle Physics that explain all phenomena observed at high energy experiments and in the universe, with a few notable exceptions. It is based on my introduction-to-elementary-particle-physics lectures for the first year graduate students at Sokendai, Graduate University for Advanced Studies. No new observation is made, but I think that it is important for us to examine the LHC data from the GUT viewpoint together with our fresh students.

    16. Two-dimensional topological order of kinetically constrained quantum particles

      NASA Astrophysics Data System (ADS)

      Kourtis, Stefanos

      2015-03-01

      Motivated by recent experimental and theoretical work on driven optical lattices, we investigate how imposing kinetic restrictions on quantum particles that would otherwise hop freely on a two-dimensional lattice can lead to topologically ordered states. The kinetically constrained models introduced here are derived as an approximate generalization of strongly interacting particles hopping on Haldane and equivalent lattices and are pertinent to systems irradiated by circularly polarized light. After introducing a broad class of models, we focus on particular realizations and show numerically that they exhibit topological order, by observing topological ground-state degeneracies and the quantization of corresponding invariants. Apart from potentially being crucial for the interpretation of forthcoming cold-atom experiments, our results also hint at unexplored possibilities for the realization of topologically ordered matter. A further implication, relevant to fractional quantum Hall (FQH) physics, is that the correlations responsible for FQH-like states can arise from processes other than density-density interactions. Financial support from EPSRC (Grant No. EP/K028960/1) and ICAM Branch Contributions.

    17. The CMS Masterclass and Particle Physics Outreach

      NASA Astrophysics Data System (ADS)

      Cecire, Kenneth; Bardeen, Marjorie; McCauley, Thomas

      2014-04-01

      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.

    18. 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.

    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. 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. PMID:27540827

    2. 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.

    3. Japanese particle-physics leader dies

      NASA Astrophysics Data System (ADS)

      Durrani, Matin

      2008-08-01

      Yoji Totsuka, former director general of the KEK particle-physics lab in Japan, died on 10 July at the age of 66. Totsuka, whose research interests were in the field of neutrino physics, served as KEK boss for three years from April 2003. After retiring in 2006, Totsuka became a professor emeritus at KEK and the University of Tokyo. His funeral on 12 July was attended by more than 500 people.

    4. 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.

    5. Particle Physics Outreach to Secondary Education

      NASA Astrophysics Data System (ADS)

      Erik Johansson, K.; Jean Young, M.

      2011-11-01

      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.

    6. 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.

    7. 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

    8. 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

    9. 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.

    10. 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…

    11. 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.

    12. Is Particle Physics Ready for the LHC

      ScienceCinema

      Lykken, Joseph

      2009-09-01

      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.

    13. 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.

    14. Is Particle Physics Ready for the LHC

      SciTech Connect

      Lykken, Joseph

      2006-04-05

      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.

    15. Is Particle Physics Ready for the LHC?

      SciTech Connect

      Lykken, Joseph

      2006-04-05

      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.

    16. Hausdorff dimension of a particle path in a quantum manifold

      SciTech Connect

      Nicolini, Piero; Niedner, Benjamin

      2011-01-15

      After recalling the concept of the Hausdorff dimension, we study the fractal properties of a quantum particle path. As a novelty we consider the possibility for the space where the particle propagates to be endowed with a quantum-gravity-induced minimal length. We show that the Hausdorff dimension accounts for both the quantum mechanics uncertainty and manifold fluctuations. In addition the presence of a minimal length breaks the self-similarity property of the erratic path of the quantum particle. Finally we establish a universal property of the Hausdorff dimension as well as the spectral dimension: They both depend on the amount of resolution loss which affects both the path and the manifold when quantum gravity fluctuations occur.

    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. 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'. PMID:27458261

    19. 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.

    20. 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.

      1. 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.

      2. 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.

      3. 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.

      4. 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.

      5. 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.

      6. New developments in photodetection for particle physics and nuclear physics

        NASA Astrophysics Data System (ADS)

        Elias, J. E.

        2000-03-01

        Photodetectors are widely used in particle and nuclear physics research. Since the beginning of the modern era of photoelectric transducers in the late 1930s, many types of devices have been developed and exploited for physics research. New performance requirements arising in physics experiments have often provided very interesting technological drivers for industry. New ideas for photo-detection are rapidly adapted by the physics community to enable more powerful experimental capabilities. This report gives a sampling of new developments in photodetection for physics research in the period since the first conference in this series, Beaune 96. Representative examples of advances in vacuum devices, solid-state devices and gaseous photodetectors are described including, where appropriate, areas where technological improvements are needed or expected.

      7. 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.

      8. Synthesis and optical properties of quantum-size metal sulfide particles in aqueous solution

        SciTech Connect

        Nedeljkovic, J.M.; Patel, R.C.; Kaufman, P.; Joyce-Pruden, C.; O'Leary, N. )

        1993-04-01

        During the past decade, small-particle' research has become quite popular in various fields of chemistry and physics. The recognition of quantum-size effects in very small colloidal particles has led to renewed interest in this area. Small particles' are clusters of atoms or molecules ranging in size from 1 nm to almost 10 nm or having agglomeration numbers from 10 up to a few hundred. In other words, small particles fall in size between single atoms or molecules and bulk materials. The agglomeration number specifies the number of individual atoms or molecules in a given cluster. The research in this area is interdisciplinary, and it links colloidal science and molecular chemistry. The symbiosis of these two areas of research has revealed some intriguing characteristics of small particles. This experiment illustrates the following: simple colloidal techniques for the preparation of two different types of quantum-size metal sulfide particles; the blue shift of the measured optical absorption spectra when the particle size is decreased in the quantum-size regime; and use of a simple quantum mechanical model to calculate the particle size from the absorption onset measured for CdS.

      9. Particle Physics Outreach for Secondary Education

        NASA Astrophysics Data System (ADS)

        Pasero, Spencer

        2013-04-01

        We provide a general overview of activities that particle physicists have developed to reach out to teachers and students. There is a remarkable worldwide interest in particle physics stimulated by the search for the Higgs Boson and a remarkable worldwide interest on the part of physicists to inspire today's students and tomorrow's scientists. While most students will not become physicists, they do need to understand how scientists discover knowledge---their ideas and methodology. We explore three types of activities: informal opportunities for students and resources for teachers, professional development for teachers and research experiences for teachers and students alike. We provide some suggestions for developing and assessing effective programs.

      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. 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…

      12. 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

      13. 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.

      14. Dirac particle in a box, and relativistic quantum Zeno dynamics

        NASA Astrophysics Data System (ADS)

        Menon, Govind; Belyi, Sergey

        2004-09-01

        After developing a complete set of eigenfunctions for a Dirac particle restricted to a box, the quantum Zeno dynamics of a relativistic system is considered. The evolution of a continuously observed quantum mechanical system is governed by the theorem put forth by Misra and Sudarshan. One of the conditions for quantum Zeno dynamics to be manifest is that the Hamiltonian is semi-bounded. This Letter analyzes the effects of continuous observation of a particle whose time evolution is generated by the Dirac Hamiltonian. The theorem by Misra and Sudarshan is not applicable here since the Dirac operator is not semi-bounded.

      15. 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.

      16. 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.

      17. Two-particle quantum correlations at graphene edges

        NASA Astrophysics Data System (ADS)

        Gräfe, Markus; Szameit, Alexander

        2015-09-01

        Its remarkable properties render graphene—in its pure and artificial forms—one of the most attractive materials in current research, with major attention given to the topological edge states at the bearded and zigzag edge. In our work, we exploit these quasi-one-dimensional (1D) systems in terms of quantum transport and quantum random walks and investigate how two-particle quantum states evolve at these edges. We find that their quantum correlation dynamics are clearly influenced by the lattice geometry and elaborate on the differences to those in genuine 1D lattices.

      18. 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…

      19. 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…

      20. 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.

      1. 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.

      2. 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.

      3. 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.

      4. 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.

      5. 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

      6. 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.

      7. 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…

      8. 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.

      9. 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.

      10. 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.

      11. 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.

      12. 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

      13. 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.

      14. 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.

      15. 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.

      16. 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.

      17. Persistent Currents and Quantum Critical Phenomena in Mesoscopic Physics

        NASA Astrophysics Data System (ADS)

        Zelyak, Oleksandr

        In this thesis, we study persistent currents and quantum critical phenomena in the systems of mesoscopic physics. As an introduction in Chapter 1 we familiarize the reader with the area of mesoscopic physics. We explain how mesoscopic systems are different from quantum systems of single atoms and molecules and bulk systems with an Avogadro number of elements. We also describe some important mesoscopic phenomena. One of the mathematical tools that we extensively use in our studies is Random Matrix Theorty. This theory is not a part of standard physics courses and for educational purposes we provide the basics of Random Matrix Theory in Chapter 2. In Chapter 3 we study the persistent current of noninteracting electrons in quantum billiards. We consider simply connected chaotic Robnik-Berry quantum billiard and its annular analog. The electrons move in the presence of a point-like magnetic flux at the center of the billiard. For the simply connected billiard, we find a large diamagnetic contribution to the persistent current at small flux, which is independent of the flux and is proportional to the number of electrons (or equivalently the density since we keep the area fixed). The size of this diamagnetic contribution is much larger than the previously studied mesoscopic fluctuations in the persistent current in the simply connected billiard. This behavior of persistent current can ultimately be traced to the response of the angular-momentum l = 0 levels (neglected in semiclassical expansions) on the unit disk to a point-like flux at its center. We observe the same behavior for the annular billiard when the inner radius is much smaller than the outer one. We also find that the usual fluctuating persistent current and Anderson-like localization due to boundary scattering are seen when the annulus tends to a one-dimensional ring. We explore the conditions for the observability of this phenomenon. In Chapter 4 we study quantum critical phenomena in a system of two

      18. The Coming Revolutions in Particle Physics

        ScienceCinema

        Quigg, Chris

        2009-09-01

        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. 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.

      19. The Coming Revolutions in Particle Physics

        SciTech Connect

        Quigg, Chris

        2008-01-18

        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.

      20. The Coming Revolutions in Particle Physics

        SciTech Connect

        Quigg, Chris

        2004-04-28

        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.

      1. 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.

        2015-09-01

        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. Furthermore, a coherent picture of nuclear structure and dynamics emerges based upon rather simple but realistic interactions and currents.

      2. Quantum Monte Carlo methods for nuclear physics

        DOE PAGESBeta

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

        2015-09-01

        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,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

      3. Quantum Monte Carlo methods for nuclear physics

        DOE PAGESBeta

        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-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

      4. 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.

      5. 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.

      6. Identical Quantum Particles and Weak Discernibility

        NASA Astrophysics Data System (ADS)

        Dieks, Dennis; Versteegh, Marijn A. M.

        2008-10-01

        Saunders has recently claimed that “identical quantum particles” with an anti-symmetric state (fermions) are weakly discernible objects, just like irreflexively related ordinary objects in situations with perfect symmetry (Black’s spheres, for example). Weakly discernible objects have all their qualitative properties in common but nevertheless differ from each other by virtue of (a generalized version of) Leibniz’s principle, since they stand in relations an entity cannot have to itself. This notion of weak discernibility has been criticized as question begging, but we defend and accept it for classical cases likes Black’s spheres. We argue, however, that the quantum mechanical case is different. Here the application of the notion of weak discernibility indeed is question begging and in conflict with standard interpretational ideas. We conclude that the introduction of the conceptual resource of weak discernibility does not change the interpretational status quo in quantum mechanics.

      7. Connecting nuclear physics to quantum chromodynamics

        SciTech Connect

        Phillips, Daniel R.

        2011-10-27

        I discuss how effective theories and numerical simulations of Quantum Chromodynamics are together helping us understand the interaction between neutrons and protons. Explicit numerical evaluation of the QCD path integral, using lattice methods and super-computers, appears to be the best option for calculations of QCD in the non-perturbative regime. I show that complementary information is provided by effective theories, which can help to relate these intensive ''lattice QCD'' calculations to nuclear-physics experiments. I place particular emphasis on the way in which the long-distance symmetries of QCD observed in lattice simulations constrain the interactions of neutrons and protons with one another, and I show how this leads to predictions for electron scattering from light nuclei.

      8. Photonic dark matter portal and quantum physics

        NASA Astrophysics Data System (ADS)

        Alavi, S. A.; Kazemian, F. S.

        2016-02-01

        We study a model of dark matter in which the hidden sector interacts with standard model particles via a hidden photonic portal. We investigate the effects of this new interaction on the hydrogen atom, including the Stark, Zeeman and hyperfine effects. Using the accuracy of the measurement of energy, we obtain an upper bound for the coupling constant of the model as f ⩽ 10-12. We also calculate the contribution from the hidden photonic portal to the anomalous magnetic moment of the muon as aμ ⩽ 2.2 × 10-23 (for the dark particle mass scale 100 MeV), which provides an important probe of physics beyond the standard model.

      9. 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

      10. 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.

      11. Quantum Delayed-Choice Experiment and Wave-Particle Superposition

        NASA Astrophysics Data System (ADS)

        Guo, Qi; Cheng, Liu-Yong; Wang, Hong-Fu; Zhang, Shou

        2015-08-01

        We propose a simple implementation scheme of quantum delayed-choice experiment in linear optical system without initial entanglement resource. By choosing different detecting devices, one can selectively observe the photon's different behaviors after the photon has been passed the Mach-Zehnder interferometer. The scheme shows that the photon's wave behavior and particle behavior can be observed with a single experimental setup by postselection, that is, the photon can show the superposition behavior of wave and particle. Especially, we compare the wave-particle superposition behavior and the wave-particle mixture behavior in detail, and find the quantum interference effect between wave and particle behavior, which may be helpful to reveal the nature of photonessentially.

      12. 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

      13. 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.

      14. 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.

      15. Topics in theoretical particle physics and cosmology

        NASA Astrophysics Data System (ADS)

        Salem, Michael Phillip

        We first delve into particle phenomenology with a study of soft-collinear effective theory (SCET), an effective theory for Quantum Chromodynamics for when all particles are approximately on their light-cones. In particular, we study the matching of SCET(I) involving ultrasoft and collinear particles onto SCET(II) involving soft and collinear particles. We show that the modes in SCET(II) are sufficient to reproduce all of the infrared divergences of SCET(I), a result that was previously in contention.Next we move into early universe cosmology and study alternative mechanisms for generating primordial density perturbations. We study the inhomogeneous reheating mechanism and extend it to describe the scenario where the freeze-out process for a heavy particle is modulated by sub-dominant fields that received fluctuations during inflation. This scenario results in perturbations that are comparable to those generated by the original inhomogeneous reheating scenarios. In addition, we study yet another alternative to single field inflation whereby the curvature perturbation is generated by interactions at the end of inflation, as opposed to when inflaton modes exit the horizon. We clarify the circumstances under which this process can dominate over the standard one and we show that it may result in a spectrum with an observable level of non-Gaussianities.We then turn to studies of the landscape paradigm, which hypothesizes that the observed universe is just one among a multitude of possibilities that are realized in separate causal regions. Such a landscape has been used to explain the smallness of the cosmological constant, at least when only it scans across the landscape. We study the scenario where both the cosmological constant and the strength of gravity, parameterized by the effective Planck mass, scan across the landscape. We find that selection effects acting on the cosmological constant are significantly weaker in this scenario and we find the measured value of

      16. 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.

      17. The Philosophy of Fields and Particles in Classical and Quantum Mechanics, Including the Problem of Renormalisation.

        NASA Astrophysics Data System (ADS)

        Huggett, Nick

        1995-01-01

        This work first explicates the philosophy of classical and quantum fields and particles. I am interested in determining how science can have a metaphysical dimension, and then with the claim that the quantum revolution has an important metaphysical component. I argue that the metaphysical implications of a theory are properties of its models, as classical mechanics determines properties of atomic diversity and temporal continuity with its representations of distinct, continuous trajectories. It is often suggested that classical statistical physics requires that many particle states be represented so that permuting properties leads to distinct states; this implies that individuals can be reidentified across possible worlds in a non-qualitative way. I show there is no evidence for this conclusion, an important result, for it is claimed that quantum particles are not individuals. This claim is based on the misconception about classical statistics, but also on a conflation of notions of identity; I show that, while transworld identity is incompatible with quantum mechanics, other classical notions may be consistently ascribed. I also give a field-particle distinction that applies usefully in both quantum and classical domains. In the former the distinction helps defeat claims of underdetermined by data, in the latter it helps provide a minimal field metaphysics. Next I tackle renormalisation: I show how divergences occur in approximate, perturbative calculations, and demonstrate how finite, empirically verified, answers are obtained. These techniques seem to show that the predictions are not logical consequences of the exact theory. I use the techniques of the renormalisation group to establish that perturbative renormalised quantum field theory does indeed approximate the consequences of field theory. Finally, I discuss the idea (Cao and Schweber, 1994) that renormalisation proves that there can be no quantum theory of everything, only a patchwork of effective

      18. (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.

      19. 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.

      20. 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)

      1. Quantum interference effects in particle transport through square lattices.

        PubMed

        Cuansing, E; Nakanishi, H

        2004-12-01

        We study the transport of a quantum particle through square lattices of various sizes by employing the tight-binding Hamiltonian from quantum percolation. Input and output semi-infinite chains are attached to the lattice either by diagonal point-to-point contacts or by a busbar connection. We find resonant transmission and reflection occurring whenever the incident particle's energy is near an eigenvalue of the lattice alone (i.e., the lattice without the chains attached). We also find the transmission to be strongly dependent on the way the chains are attached to the lattice. PMID:15697469

      2. 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.

      3. 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.

      4. 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.

      5. Quantum mechanical tunneling of composite particle systems: Linkage to sub-barrier nuclear reactions

        SciTech Connect

        Shotter, A. C.; Shotter, M. D.

        2011-05-15

        A variety of physical phenomena have at their foundation the quantum tunneling of particles through potential barriers. Many of these phenomena can be associated with the tunneling of single inert particles. The tunneling of composite systems is more complex than for single particles due to the coupling of the tunneling coordinate with the internal degrees of freedom of the tunneling system. Reported here are the results of a study for the tunneling of a two-component projectile incident on a potential energy system which differs for the two components. A specific linkage is made to sub-Coulomb nuclear reactions.

      6. 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.

      7. Lagrangian dynamics for classical, Brownian, and quantum mechanical particles

        NASA Astrophysics Data System (ADS)

        Pavon, Michele

        1996-07-01

        In the framework of Nelson's stochastic mechanics [E. Nelson, Dynamical Theories of Brownian Motion (Princeton University, Princeton, 1967); F. Guerra, Phys. Rep. 77, 263 (1981); E. Nelson, Quantum Fluctuations (Princeton University, Princeton, 1985)] we seek to develop the particle counterpart of the hydrodynamic results of M. Pavon [J. Math. Phys. 36, 6774 (1995); Phys. Lett. A 209, 143 (1995)]. In particular, a first form of Hamilton's principle is established. We show that this variational principle leads to the correct equations of motion for the classical particle, the Brownian particle in thermodynamical equilibrium, and the quantum particle. In the latter case, the critical process q satisfies a stochastic Newton law. We then introduce the momentum process p, and show that the pair (q,p) satisfies canonical-like equations.

      8. 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.

      9. 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.

      10. Particle physics confronts the solar neutrino problem

        SciTech Connect

        Pal, P.B.

        1991-06-01

        This review has four parts. In Part I, we describe the reactions that produce neutrinos in the sun and the expected flux of those neutrinos on the earth. We then discuss the detection of these neutrinos, and how the results obtained differ from the theoretical expectations, leading to what is known as the solar neutrino problem. In Part II, we show how neutrino oscillations can provide a solution to the solar neutrino problem. This includes vacuum oscillations, as well as matter enhanced oscillations. In Part III, we discuss the possibility of time variation of the neutrino flux and how a magnetic moment of the neutrino can solve the problem. WE also discuss particle physics models which can give rise to the required values of magnetic moments. In Part IV, we present some concluding remarks and outlook for the recent future.

      11. Energy related applications of elementary particle physics

        SciTech Connect

        Rafelski, J.

        1991-08-31

        The current research position is summarized, and what could be done in the future to clarify issues which were opened up by the research is indicated. Following on the discussion of the viability of catalyzed fusion, there is presented along with the key experimental results, a short account of the physics surrounding the subject. This is followed by a discussion of key research topics addressed. In consequence of the progress made, it appears that the feasibility of a small-scale fusion based on catalyzed reactions rests on either the remote chance that a yet undiscovered ultraheavy negatively charged elementary particle exists in Nature, or on the possible technical realization of a system based on muon-catalyzed fusion (MuCF) in high-density degenerate hydrogen plasma (density 1000 LHD, temperature O(100 eV)). The lattter is considered to have practical promise.

      12. 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…

      13. 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.

      14. 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.

      15. Lindblad- and non-Lindblad-type dynamics of a quantum Brownian particle

        SciTech Connect

        Maniscalco, S.; Piilo, J.; Intravaia, F.; Petruccione, F.; Messina, A.

        2004-09-01

        The dynamics of a typical open quantum system, namely a quantum Brownian particle in a harmonic potential, is studied focusing on its non-Markovian regime. Both an analytic approach and a stochastic wave-function approach are used to describe the exact time evolution of the system. The border between two very different dynamical regimes, the Lindblad and non-Lindblad regimes, is identified and the relevant physical variables governing the passage from one regime to the other are singled out. The non-Markovian short-time dynamics is studied in detail by looking at the mean energy, the squeezing, the Mandel parameter, and the Wigner function of the system.

      16. Quantum-Behaved Particle Swarm Optimization with Chaotic Search

        NASA Astrophysics Data System (ADS)

        Yang, Kaiqiao; Nomura, Hirosato

        The chaotic search is introduced into Quantum-behaved Particle Swarm Optimization (QPSO) to increase the diversity of the swarm in the latter period of the search, so as to help the system escape from local optima. Taking full advantages of the characteristics of ergodicity and randomicity of chaotic variables, the chaotic search is carried out in the neighborhoods of the particles which are trapped into local optima. The experimental results on test functions show that QPSO with chaotic search outperforms the Particle Swarm Optimization (PSO) and QPSO.

      17. Time and a physical Hamiltonian for quantum gravity.

        PubMed

        Husain, Viqar; Pawłowski, Tomasz

        2012-04-01

        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. PMID:22540782

      18. 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

      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. Quantum phase transition in trigonal triple quantum dots: The case of quantum dots deviated from particle-hole symmetric point

        NASA Astrophysics Data System (ADS)

        Kim, Song-Hyok; Kang, Chol-Jin; Kim, Yon-Il; Kim, Kwang-Hyon

        2015-05-01

        We consider a triple quantum dot system in a triangular geometry with one of the dots connected to metallic leads. We investigate quantum phase transition between local moment phase and Kondo screened strong coupling phase in triple quantum dots where energy levels of dots are deviated from the particle-hole symmetric point. The effect of on-site energy of dots on quantum phase transition between local moment phase and Kondo screened strong coupling phase in triple quantum dots is studied based on the analytical arguments and the numerical renormalization group method. The results show that the critical value of tunnel coupling between side dots decreases when the energy level of embedded dot rises up from the symmetric point to the Fermi level and the critical value increases when the energy levels of two side dots rise up. The study of the influence of on-site-energy changes on the quantum phase transitions in triple quantum dots has the importance for clarifying the mechanism of Kondo screening in triple quantum dots where energy levels of dots are deviated from the particle-hole symmetric point.

      1. Quantum states of two particles on concentric spheres

        NASA Astrophysics Data System (ADS)

        Ezra, Gregory S.; Berry, R. Stephen

        1983-10-01

        The model of two particles on a sphere is extended to two particles on concentric spheres (POCS). The quantum states are found for two electrons, one on a sphere of radius 10 a.u. (simulating the shell n=3 in He) and the other, on spheres of 10, 15, 25, 50, and 100 a.u. The eigenvalues and densities ρ(θ12) exhibit a transition from collective, moleculelike behavior to independent-particle-like behavior with Russell-Saunders coupling. The parallel problem of two particles with electron masses interacting via a repulsive Gaussian potential is also treated and a similar transition from collective to independent-particle behavior found. The principal difference between the two cases is only the region of radius of the larger sphere where the transition occurs.

      2. 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…

      3. Long-time behavior of many-particle quantum decay

        SciTech Connect

        Campo, A. del

        2011-07-15

        While exponential decay is ubiquitous in nature, deviations at both short and long times are dictated by quantum mechanics. Nonexponential decay is known to arise due to the possibility of reconstructing the initial state from the decaying products. We discuss the quantum decay dynamics by tunneling of a many-particle system, characterizing the long-time nonexponential behavior of the nonescape and survival probabilities. The effects of contact interactions and quantum statistics are described. It is found that, whereas for noninteracting bosons the long-time decay follows a power law with an exponent linear in the number of particles N, the exponent becomes quadratic in N in the fermionic case. The same results apply to strongly interacting many-body systems related by the generalized Bose-Fermi duality. The faster fermionic decay can be traced back to the effective hard-core interactions between particles, which are as well the decaying products, and exhibit spatial antibunching which hinders the reconstruction of the initial unstable state. The results are illustrated with a paradigmatic model of quantum decay from a trap allowing leaks by tunneling, whose dynamics is described exactly by means of an expansion in resonant states.

      4. 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)

      5. 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.

      6. Quantum interference effects in particle transport through square lattices

        NASA Astrophysics Data System (ADS)

        Cuansing, E.; Nakanishi, H.

        2004-12-01

        We study the transport of a quantum particle through square lattices of various sizes by employing the tight-binding Hamiltonian from quantum percolation. Input and output semi-infinite chains are attached to the lattice either by diagonal point-to-point contacts or by a busbar connection. We find resonant transmission and reflection occurring whenever the incident particle’s energy is near an eigenvalue of the lattice alone (i.e., the lattice without the chains attached). We also find the transmission to be strongly dependent on the way the chains are attached to the lattice.

      7. 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.

      8. 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.

      9. J. J. Sakurai Prize for Theoretical Particle Physics Lecture: Particle physics after the first LHC results

        NASA Astrophysics Data System (ADS)

        Altarelli, Guido

        2012-03-01

        The LHC results released so far have very much restricted the possible range for the Standard Model Higgs boson mass. Moreover some indications for a signal at a mass around 125 GeV have been found. At the same time, no clear evidence for new physics has emerged from the LHC data. We discuss the impact of these results on our understanding of particle physics. The presently allowed window for the Higgs mass and the negative results for exotic particles are compatible with both the Standard model and its Supersymmetric extensions but imply considerable restrictions and need a substantial amount of fine tuning in all cases. We discuss the options that remain open and the perspectives for the near future.

      10. 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.

      11. Quantum physics: Destruction of discrete charge

        NASA Astrophysics Data System (ADS)

        Nazarov, Yuli V.

        2016-08-01

        Electric charge is quantized in units of the electron's charge. An experiment explores the suppression of charge quantization caused by quantum fluctuations and supports a long-standing theory that explains this behaviour. See Letter p.58

      12. 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.

      13. Asymptotic neutron scattering laws for anomalously diffusing quantum particles

        NASA Astrophysics Data System (ADS)

        Kneller, Gerald R.

        2016-07-01

        The paper deals with a model-free approach to the analysis of quasielastic neutron scattering intensities from anomalously diffusing quantum particles. All quantities are inferred from the asymptotic form of their time-dependent mean square displacements which grow ∝tα, with 0 ≤ α < 2. Confined diffusion (α = 0) is here explicitly included. We discuss in particular the intermediate scattering function for long times and the Fourier spectrum of the velocity autocorrelation function for small frequencies. Quantum effects enter in both cases through the general symmetry properties of quantum time correlation functions. It is shown that the fractional diffusion constant can be expressed by a Green-Kubo type relation involving the real part of the velocity autocorrelation function. The theory is exact in the diffusive regime and at moderate momentum transfers.

      14. Asymptotic neutron scattering laws for anomalously diffusing quantum particles.

        PubMed

        Kneller, Gerald R

        2016-07-28

        The paper deals with a model-free approach to the analysis of quasielastic neutron scattering intensities from anomalously diffusing quantum particles. All quantities are inferred from the asymptotic form of their time-dependent mean square displacements which grow ∝t(α), with 0 ≤ α < 2. Confined diffusion (α = 0) is here explicitly included. We discuss in particular the intermediate scattering function for long times and the Fourier spectrum of the velocity autocorrelation function for small frequencies. Quantum effects enter in both cases through the general symmetry properties of quantum time correlation functions. It is shown that the fractional diffusion constant can be expressed by a Green-Kubo type relation involving the real part of the velocity autocorrelation function. The theory is exact in the diffusive regime and at moderate momentum transfers. PMID:27475344

      15. 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.

      16. 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.

      17. Classical foundations of many-particle quantum chaos

        NASA Astrophysics Data System (ADS)

        Gutkin, Boris; Osipov, Vladimir

        2016-02-01

        In the framework of semiclassical theory the universal properties of quantum systems with classically chaotic dynamics can be accounted for through correlations between partner periodic orbits with small action differences. So far, however, the scope of this approach has been mainly limited to systems of a few particles with low-dimensional phase spaces. In the present work we consider N-particle chaotic systems with local homogeneous interactions, where N is not necessarily small. Based on a model of coupled cat maps we demonstrate emergence of a new mechanism for correlation between periodic orbit actions. In particular, we show the existence of partner orbits which are specific to many-particle systems. For a sufficiently large N these new partners dominate the spectrum of correlating periodic orbits and seem to be necessary for construction of a consistent many-particle semiclassical theory.

      18. 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…

      19. Cryptanalysis of quantum secret sharing with d -level single particles

        NASA Astrophysics Data System (ADS)

        Lin, Song; Guo, Gong-De; Xu, Yong-Zhen; Sun, Ying; Liu, Xiao-Fen

        2016-06-01

        In a recent paper [V. Karimipour and M. Asoudeh, Phys. Rev. A 92, 030301(R) (2015)], 10.1103/PhysRevA.92.030301, a multiparty quantum secret-sharing protocol based on d -level single particles was proposed. We discussed the security of this protocol and found that it is not secure for any one dishonest participant who can recover the secret without the aid of other participants.

      20. Quantification of correlations in quantum many-particle systems.

        PubMed

        Byczuk, Krzysztof; Kuneš, Jan; Hofstetter, Walter; Vollhardt, Dieter

        2012-02-24

        We introduce a well-defined and unbiased measure of the strength of correlations in quantum many-particle systems which is based on the relative von Neumann entropy computed from the density operator of correlated and uncorrelated states. The usefulness of this general concept is demonstrated by quantifying correlations of interacting electrons in the Hubbard model and in a series of transition-metal oxides using dynamical mean-field theory. PMID:22463560

      1. Colloquium: Majorana fermions in nuclear, particle, and solid-state physics

        NASA Astrophysics Data System (ADS)

        Elliott, Steven R.; Franz, Marcel

        2015-01-01

        Ettore Majorana (1906-1938) disappeared while traveling by ship from Palermo to Naples in 1938. His fate has never been fully resolved and several articles have been written that explore the mystery itself. His demise intrigues us still today because of his seminal work, published the previous year, that established symmetric solutions to the Dirac equation that describe a fermionic particle that is its own antiparticle. This work has long had a significant impact in neutrino physics, where this fundamental question regarding the particle remains unanswered. But the formalism he developed has found many uses as there are now a number of candidate spin-1 /2 neutral particles that may be truly neutral with no quantum number to distinguish them from their antiparticles. If such particles exist, they will influence many areas of nuclear and particle physics. Most notably the process of neutrinoless double beta decay can exist only if neutrinos are massive Majorana particles. Hence, many efforts to search for this process are underway. Majorana's influence does not stop with particle physics, however, even though that was his original consideration. The equations he derived also arise in solid-state physics where they describe electronic states in materials with superconducting order. Of special interest here is the class of solutions of the Majorana equation in one and two spatial dimensions at exactly zero energy. These Majorana zero modes are endowed with some remarkable physical properties that may lead to advances in quantum computing and, in fact, there is evidence that they have been experimentally observed. This Colloquium first summarizes the basics of Majorana's theory and its implications. It then provides an overview of the rich experimental programs trying to find a fermion that is its own antiparticle in nuclear, particle, and solid-state physics.

      2. 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

      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. 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.

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

        NASA Astrophysics Data System (ADS)

        Banerjee, Somaditya

        2016-05-01

        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.

      6. 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.

      7. Probing phase-space noncommutativity through quantum mechanics and thermodynamics of free particles and quantum rotors

        NASA Astrophysics Data System (ADS)

        Santos, Jonas F. G.; Bernardini, Alex E.; Bastos, Catarina

        2015-11-01

        Novel quantization properties related to the state vectors and the energy spectrum of a two-dimensional system of free particles are obtained in the framework of noncommutative (NC) quantum mechanics (QM) supported by the Weyl-Wigner formalism. Besides reproducing the magnetic field aspect of a Zeeman-like effect, the momentum space NC parameter introduces mutual information properties quantified by the quantum purity related to the relevant coordinates of the corresponding Hilbert space. Supported by the QM in the phase-space, the thermodynamic limit is obtained, and the results are extended to three-dimensional systems. The noncommutativity imprints on the thermodynamic variables related to free particles are identified and, after introducing some suitable constraints to fix an axial symmetry, the analysis is extended to two- and- three dimensional quantum rotor systems, for which the quantization aspects and the deviation from standard QM results are verified.

      8. Quantum physics with non-Hermitian operators Quantum physics with non-Hermitian operators

        NASA Astrophysics Data System (ADS)

        Bender, Carl; Fring, Andreas; Günther, Uwe; Jones, Hugh

        2012-11-01

        The main motivation behind the call for this special issue was to gather recent results, developments and open problems in quantum physics with non-Hermitian operators. There have been previous special issues in this journal [1, 2] and elsewhere on this subject. The intention of this issue is to reflect the current state of this rapidly-developing field. It has therefore been open to all contributions containing new results on non-Hermitian theories that are explicitly PT-symmetric and/or pseudo-Hermitian or quasi-Hermitian. In the last decade these types of systems have proved to be viable self-consistent physical theories with well defined unitary time-evolution and real spectra. As the large number of responses demonstrates, this is a rapidly evolving field of research. A consensus has been reached regarding most of the fundamental problems, and the general ideas and techniques are now readily being employed in many areas of physics. Nonetheless, this issue still contains some treatments of a more general nature regarding the spectral analysis of these models, in particular, the physics of the exceptional points, the breaking of the PT-symmetry, an interpretation of negative energies and the consistent implementation of the WKB analysis. This issue also contains a treatment of a scattering theory associated with these types of systems, weak measurements, coherent states, decoherence, unbounded metric operators and the inclusion of domain issues to obtain well defined self-adjoint theories. Contributions in the form of applications of the general ideas include: studies of classical shock-waves and tunnelling, supersymmetric models, spin chain models, models with ring structure, random matrix models, the Pauli equation, the nonlinear Schrödinger equation, quasi-exactly solvable models, integrable models such as the Calogero model, Bose-Einstein condensates, thermodynamics, nonlinear oligomers, quantum catastrophes, the Landau-Zener problem and pseudo

      9. Alpha Particle Physics Experiments in the Tokamak Fusion Test Reactor

        SciTech Connect

        Budny, R.V.; Darrow, D.S.; Medley, S.S.; Nazikian, R.; Zweben, S.J.; et al.

        1998-12-14

        Alpha particle physics experiments were done on the Tokamak Fusion Test Reactor (TFTR) during its deuterium-tritium (DT) run from 1993-1997. These experiments utilized several new alpha particle diagnostics and hundreds of DT discharges to characterize the alpha particle confinement and wave-particle interactions. In general, the results from the alpha particle diagnostics agreed with the classical single-particle confinement model in magnetohydrodynamic (MHD) quiescent discharges. Also, the observed alpha particle interactions with sawteeth, toroidal Alfvén eigenmodes (TAE), and ion cyclotron resonant frequency (ICRF) waves were roughly consistent with theoretical modeling. This paper reviews what was learned and identifies what remains to be understood.

      10. One hundred years of quantum physics.

        PubMed

        Kleppner, D; Jackiw, R

        2000-08-11

        This year marks the 100th anniversary of Max Planck's creation of the quantum concept, an idea so revolutionary that it took nearly 30 years for scientists to develop it into the theory that has transformed the way scientists view reality. In this month's essay, Daniel Kleppner and Roman Jackiw recount how quantum theory, which they rate as "the most precisely tested and most successful theory in the history of science," came to be, how it changed the world, and how it might continue to evolve to make the dream of ultimate understanding of the universe come true. PMID:17839156

      11. 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…

      12. 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…

      13. 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.

      14. 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.

      15. Fundamental Particles and Interactions. A Wall Chart of Modern Physics.

        ERIC Educational Resources Information Center

        Achor, William T.; And Others

        1988-01-01

        Discusses a wall chart, "The Standard Model of Fundamental Particles and Interactions," for use in introductory physics courses at either high school or college level. Describes the chart development process, introduction and terminology of particle physics, components of the chart, and suggestions for using the chart, booklet, and software. (YP)

      16. Particle-physics open-access pact finally starts up

        NASA Astrophysics Data System (ADS)

        Banks, Michael

        2014-01-01

        A collaboration of funding agencies and particle-physics labs from 24 nations around the world has reached an agreement with libraries and publishers that will see some 5000 papers a year in particle physics becoming immediately free to read online upon publication.

      17. Visualization of the Invisible: The Qubit as Key to Quantum Physics

        NASA Astrophysics Data System (ADS)

        Dür, Wolfgang; Heusler, Stefan

        2014-11-01

        Quantum mechanics is one of the pillars of modern physics, however rather difficult to teach at the introductory level due to the conceptual difficulties and the required advanced mathematics. Nevertheless, attempts to identify relevant features of quantum mechanics and to put forward concepts of how to teach it have been proposed.1-8 Here we present an approach to quantum physics based on the simplest quantum mechanical system—the quantum bit (qubit).1 Like its classical counterpart—the bit—a qubit corresponds to a two-level system, i.e., some system with a physical property that can admit two possible values. While typically a physical system has more than just one property or the property can admit more than just two values, in many situations most degrees of freedom can be considered to be fixed or frozen. Hence a variety of systems can be effectively described as a qubit. For instance, one may consider the spin of an electron or atom, with spin up and spin down as two possible values, and where other properties of the particle such as its mass or its position are fixed. Further examples include the polarization degree of freedom of a photon (horizontal and vertical polarization), two electronic degrees of freedom (i.e., two energy levels) of an atom, or the position of an atom in a double well potential (atom in left or right well). In all cases, only two states are relevant to describe the system.

      18. 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.

      19. Quantum dot solar cell tolerance to alpha-particle irradiation

        SciTech Connect

        Cress, Cory D.; Hubbard, Seth M.; Landi, Brian J.; Raffaelle, Ryne P.; Wilt, David M.

        2007-10-29

        The effects of alpha-particle irradiation on an InAs quantum dot (QD) array and GaAs-based InAs QD solar cells were investigated. Using photoluminescence (PL) mapping, the PL intensity at 872 and 1120 nm, corresponding to bulk GaAs and InAs QD emissions, respectively, were measured for a five-layer InAs QD array which had a spatially varying total alpha-particle dose. The spectral response and normalized current-voltage parameters of the solar cells, measured as a function of alpha-particle fluence, were used to investigate the change in device performance between GaAs solar cells with and without InAs QDs.

      20. Single-particle spectroscopic measurements of fluorescent graphene quantum dots.

        PubMed

        Xu, Qinfeng; Zhou, Qi; Hua, Zheng; Xue, Qi; Zhang, Chunfeng; Wang, Xiaoyong; Pan, Dengyu; Xiao, Min

        2013-12-23

        We have performed the first single-particle spectroscopic measurements on individual graphene quantum dots (GQDs) and revealed several intriguing fluorescent phenomena that are otherwise hidden in the optical studies of ensemble GQDs. First, despite noticeable differences in the size and the number of layers from particle to particle, all of the GQDs studied possess almost the same spectral lineshapes and peak positions. Second, GQDs with more layers are normally brighter emitters but are associated with shorter fluorescent lifetimes. Third, the fluorescent spectrum of GQDs was red-shifted upon being aged in air, possibly due to the water desorption effect. Finally, the missing emission of single photons and stable fluorescence without any intermittent behavior were observed from individual GQDs. PMID:24251867

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

        PubMed

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

        2013-09-01

        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

      2. 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.

      3. 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.

      4. Particle Physics Masterclass as a Context for Learning about NOS

        NASA Astrophysics Data System (ADS)

        Wadness, Michael

        2011-04-01

        This research addresses the question: Do secondary school science students attending the U.S. Particle Physics Masterclass change their view of the nature of science (NOS)? The U.S. Particle Physics Masterclass is a national physics outreach program run by QuarkNet, in which high school physics students gather at a local research institution for one day to learn about particle physics and the scientific enterprise. Student activities include introductory lectures in particle physics, laboratory tours, analysis of actual data from CERN, and the discussion of their findings in a conference-like atmosphere. Although there are a number of outreach programs involving scientists in K-12 education, very few of them have been formally evaluated to determine if they provide adequate learning of NOS. Therefore, the significance of this study is that it investigates the claim that science outreach programs may be designed to address science literacy, specifically as a context for explicit NOS instruction.

      5. 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.

      6. Synthesis of quantum chromodynamics and nuclear physics

        SciTech Connect

        Brodsky, S.J.; Lepage, G.P.

        1980-08-01

        The asymptotic freedom behavior of quantum chromodynamics allows the rigorous calculation of hadronic and nuclear amplitudes at short distances by perturbative methods. The implications of QCD for large-momentum-transfer nuclear form factors and scattering processes, as well as for the structure of nuclear wave functions and nuclear interactions at short distances, are discussed. The necessity for color-polarized internal nuclear states is also discussed. 6 figures.

      7. 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. PMID:21905841

      8. 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.

      9. Current technology of particle physics detectors

        SciTech Connect

        Ludlam, T.W.

        1986-06-23

        A brief discussion is given of the characteristics required of new accelerator facilities, leading into a discussion of the required detectors, including position sensitive detectors, particle identification, and calorimeters. (LEW)

      10. 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.

      11. Particle physics. Positrons ride the wave

        SciTech Connect

        Piot, Philippe

        2015-08-26

        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.

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

        NASA Astrophysics Data System (ADS)

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

        2014-12-01

        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 Hc of negativity and zeros of quantum capacity of quantum channels in de Sitter space has been proved.

      13. Relativistic models in nuclear and particle physics

        SciTech Connect

        Coester, F.

        1988-01-01

        A comparative overview is presented of different approaches to the construction of phenomenological dynamical models that respect basic principles of quantum theory and relativity. Wave functions defined as matrix elements of products of field operators on one hand and wave functions that are defined as representatives of state vectors in model Hilbert spaces are related differently to observables and dynamical models for these wave functions have each distinct advantages and disadvantages 34 refs.

      14. 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.

      15. 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.

      16. 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

      17. 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…

      18. 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)

      19. 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.

      20. 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.

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

        NASA Astrophysics Data System (ADS)

        Hahne, G. E.

        2013-01-01

        Muñoz, Seidel, and Muga [Phys. Rev. A 79, 012108 (2009), 10.1103/PhysRevA.79.012108], following an earlier proposal by Pollak and Miller [Phys. Rev. Lett. 53, 115 (1984), 10.1103/PhysRevLett.53.115] 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), 10.1088/0305-4470/36/25/316]; 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.

      2. Quantum dot-containing polymer particles with thermosensitive fluorescence.

        PubMed

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

        2013-01-15

        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 fabricated. The temperature 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. Embedding QDs in the PVCL shell yields particles whose fluorescence is sensitive to temperature changes. This sensitivity was determined by the dependence of the QD fluorescence intensity on the distances between them in the PVCL shell, which reversibly change as a result of the temperature-driven conformational changes in the polymer. The QD-containing thermosensitive particles were assembled with protein molecules in such a way that they retained their thermosensitive properties, including the completely reversible temperature dependence of their fluorescence response. The composite particles developed can be used as local temperature sensors, as carriers for biomolecules, as well as in biosensing and various bioassays employing optical detection schemes. PMID:22884648

      3. Weak cosmic censorship, superradiance, and quantum particle creation

        NASA Astrophysics Data System (ADS)

        Semiz, Ibrahim; Düztaş, Koray

        2015-11-01

        Starting in 2007, a string of papers argue about if the weak cosmic censorship conjecture (WCCC) can be violated by classically forbidden interactions between particles and slightly subextremal black holes, occurring via the quantum nature of the particles; and where backreaction and/or superradiance are pointed out as effects working in the direction of preserving the WCCC. We correct/modify a backreaction argument, point out that transmission/reflection coefficients for relativistic wave equations are not the respective probabilities, and conclude that superradiance does not prevent single particles from being captured by the black hole; even if this capture would lead to WCCC violation. Then we consider the spontaneous emission (which we call the Zel'dovich-Unruh "ZU" effect) of particles by the black hole, and point out that it completely invalidates the mentioned single- or few-particle thought experiments. We find that at least for scalars, the ZU effect can be understood without second quantization; and reevaluate our previous work on scalar fields interacting with black holes in view of this new understanding, finding that it becomes inconclusive.

      4. The geometric phase in quantum physics

        SciTech Connect

        Bohm, A.

        1993-03-01

        After an explanatory introduction, a quantum system in a classical time-dependent environment is discussed; an example is a magnetic moment in a classical magnetic field. At first, the general abelian case is discussed in the adiabatic approximation. Then the geometric phase for nonadiabatic change of the environment (Anandan--Aharonov phase) is introduced, and after that general cyclic (nonadiabatic) evolution is discussed. The mathematics of fiber bundles is introduced, and some of its results are used to describe the relation between the adiabatic Berry phase and the geometric phase for general cyclic evolution of a pure state. The discussion is restricted to the abelian, U(1) phase.

      5. Particle size, surface coating, and PEGylation influence the biodistribution of quantum dots in living mice.

        PubMed

        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; Gambhir, Sanjiv S

        2009-01-01

        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

      6. 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.

      7. 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).

      8. Mapping of topological quantum circuits to physical hardware.

        PubMed

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

        2014-01-01

        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. PMID:24722360

      9. Mapping of Topological Quantum Circuits to Physical Hardware

        NASA Astrophysics Data System (ADS)

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

        2014-04-01

        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.

      10. 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

      11. 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.

      12. Celebrating 40 years of research in Journal of Physics G: Nuclear and Particle Physics

        NASA Astrophysics Data System (ADS)

        Adcock, Colin D.; Martin, Alan D.; Schwenk, Achim

        2015-09-01

        2015 marks the 40th anniversary of Journal of Physics G: Nuclear and Particle Physics. This editorial provides a brief history of the journal, and introduces a unique collection of invited articles from leading authors to celebrate the occasion.

      13. 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.

      14. 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.

      15. 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...

      16. Free-Dirac-particle evolution as a quantum random walk

        NASA Astrophysics Data System (ADS)

        Bracken, A. J.; Ellinas, D.; Smyrnakis, I.

        2007-02-01

        It is known that any positive-energy state of a free Dirac particle that is initially highly localized evolves in time by spreading at speeds close to the speed of light. As recently indicated by Strauch, this general phenomenon, and the resulting “two-horned” distributions of position probability along any axis through the point of initial localization, can be interpreted in terms of a quantum random walk, in which the roles of “coin” and “walker” are naturally associated with the spin and translational degrees of freedom in a discretized version of Dirac’s equation. We investigate the relationship between these two evolutions analytically and show how the evolved probability density on the x axis for the Dirac particle at any time t can be obtained from the asymptotic form of the probability distribution for the position of a “quantum walker.” The case of a highly localized initial state is discussed as an example.

      17. 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. PMID:15783824

      18. 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,…

      19. Quantum Physics and Mental Health Counseling: The Time Is...!

        ERIC Educational Resources Information Center

        Gerstein, Lawrence H.; Bennett, Matt

        1999-01-01

        Introduces a new framework of mental health counseling based on quantum physics. The framework stresses systemic thinking and intervention, interdependence, and the importance of adopting a novel perspective about time, space, reality, and change. This framework has the potential of modifying mental health counseling practice and training. Offers…

      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. 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.

      2. 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)

      3. Future particle-physics projects in the United States

        SciTech Connect

        Denisov, D. S.

        2015-07-15

        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.

      4. 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.

      5. 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…

      6. Future particle-physics projects in the United States

        NASA Astrophysics Data System (ADS)

        Denisov, D. S.

        2015-07-01

        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.

      7. Insights and Puzzles in Particle Physics

        NASA Astrophysics Data System (ADS)

        Leutwyler, H.

        2015-03-01

        I briefly review the conceptual developments that led to the Standard Model and discuss some of its remarkable qualitative features. On the way, I draw attention to several puzzling aspects that are beyond the reach of our present understanding of the basic laws of physics.

      8. Insights and puzzles in particle physics

        NASA Astrophysics Data System (ADS)

        Leutwyler, H.

        2015-01-01

        I briefly review the conceptual developments that led to the Standard Model and discuss some of its remarkable qualitative features. On the way, I draw attention to several puzzling aspects that are beyond the reach of our present understanding of the basic laws of physics.

      9. 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.

      10. 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.

      11. 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)

      12. 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.

      13. 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.

      14. Quantum hydrodynamics approach to the formation of waves in polarized two-dimensional systems of charged and neutral particles

        SciTech Connect

        Andreev, P. A.; Kuzmenkov, L. S.; Trukhanova, M. I.

        2011-12-15

        In this paper, we explicate a method of quantum hydrodynamics (QHD) for the study of the quantum evolution of a system of polarized particles. Although we focused primarily on the two-dimensional (2D) physical systems, the method is valid for three-dimensional (3D) and one-dimensional (1D) systems too. The presented method is based upon the Schroedinger equation. Fundamental QHD equations for charged and neutral particles were derived from the many-particle microscopic Schroedinger equation. The fact that particles possess the electric dipole moment (EDM) was taken into account. The explicated QHD approach was used to study dispersion characteristics of various physical systems. We analyzed dispersion of waves in a two-dimensional ion and hole gas placed into an external electric field, which is orthogonal to the gas plane. Elementary excitations in a system of neutral polarized particles were studied for 1D, 2D, and 3D cases. The polarization dynamics in systems of both neutral and charged particles is shown to cause formation of a new type of waves as well as changes in the dispersion characteristics of already known waves. We also analyzed wave dispersion in 2D exciton systems, in 2D electron-ion plasma, and in 2D electron-hole plasma. Generation of waves in 3D-system neutral particles with EDM by means of the beam of electrons and neutral polarized particles is investigated.

      15. Quantum mechanical and semi-classical treatment of quantum excitations due to the passage of a particle

        NASA Astrophysics Data System (ADS)

        van Dijk, W.; Kiers, K. A.; Nogami, Y.; Platt, A.; Spyksma, K.

        2003-05-01

        We examine the validity of the approximation in which an alpha particle interacting with an atom is treated classically. In order to analyse such interactions, we perform a model simulation in which the alpha particle is considered as a particle in one dimension, and the atom as a quantum two-level system. The particle impinges on and excites the two-level system. We treat the particle in two ways: as a quantum mechanical wave packet, and as a classical particle. The classical particle may be a point or may have an extended structure. In each case we calculate the excitation probability P21(t) as a function of time t. We focus on the situation in which the kinetic energy of the incident particle well exceeds the excitation energy of the two-level system. Although the finite-time behaviour of P21(t) varies, P21(infty) is remarkably insensitive to the size and shape of the incident wave packet in the quantum mechanical treatment. In the classical treatment, in contrast, we find that P21(infty) is sensitive to the size of the particle. The classical point particle, however, yields nearly the same values of P21(infty) as the quantum wave packet. Implications of the results on the interaction between an alpha particle and an atom are discussed.

      16. 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.

      17. 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

      18. 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.

      19. 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.

      20. 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.

      1. J-PARC Status, Nuclear and Particle Physics

        SciTech Connect

        Sato, Susumu

        2011-06-01

        J-PARC accelerator research complex, consisting of LINAC, RCS and MR synchrotron, has successfully produced neutron, muons, kaons, and neutrinos by steady commissioning since November 2006. There are three experimental facilities, and for nuclear and particle physics, nine experiments are approved in a hadron physics facility, and one experiment is approved in a neutrino physics facility. Those experiments and status of J-PARC are described in this paper.

      2. 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;…

      3. 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.

      4. 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.

      5. The Art and Science of Experimentation in Quantum Physics

        NASA Astrophysics Data System (ADS)

        Plotnitsky, Arkady

        2010-05-01

        Taking its historical point of departure in Heisenberg's work, this article offers a view of quantum mechanics as, arguably, the first truly experimental and truly mathematical physical theory, that is, a theory concerned with experimenting with nature and mathematics alike. It is truly experimental because it is not, as in classical physics, merely the independent behavior of the system considered, in other words, what happens in any event, that we track, but what kind of experiments we perform that defines what happens. By the same token, the theory is also truly mathematical because, at least in the interpretation adopted here, its mathematical formalism does not stand in the service of a mathematical description of (quantum) physical processes in space and time in the way the formalism of classical physics does, but is only used to predict the outcomes of relevant experiments. It also follows that quantum theories experiment more freely with mathematics itself, since we invent predictive mathematical schemes, rather than proceed by refining mathematically our phenomenal representations of nature, which process constrains us in classical mechanics.

      6. Ionic conductivity in a quantum lattice gas model with three-particle interactions

        NASA Astrophysics Data System (ADS)

        Barry, J. H.; Muttalib, K. A.; Tanaka, T.

        2012-12-01

        A system of mesoscopic ions with dominant three-particle interactions is modeled by a quantum lattice liquid on the planar kagomé lattice. The two-parameter Hamiltonian contains localized attractive triplet interactions as potential energy and nearest neighbor hopping-type terms as kinetic energy. The dynamic ionic conductivity σ(ω) is theoretically investigated for ‘weak hopping’ via a quantum many-body perturbation expansion of the thermal (Matsubara) Green function (current-current correlation). A simple analytic continuation and mapping of the thermal Green function provide the temporal Fourier transform of the physical retarded Green function in the Kubo formula. Substituting pertinent exact solutions for static multi-particle correlations known from previous work, Arrhenius relations are revealed in zeroth-order approximation for the dc ionic conductivity σdc along special trajectories in density-temperature space. The Arrhenius plots directly yield static activation energies along the latter loci. Experimental possibilities relating to σdc are discussed in the presence of equilibrium aggregation. This article is part of ‘Lattice models and integrability’, a special issue of Journal of Physics A: Mathematical and Theoretical in honour of F Y Wu's 80th birthday.

      7. Thermal pure quantum states of many-particle systems

        NASA Astrophysics Data System (ADS)

        Hyuga, Masahiko; Sugiura, Sho; Sakai, Kazumitsu; Shimizu, Akira

        2014-09-01

        We generalize the thermal pure quantum (TPQ) formulation of statistical mechanics, in such a way that it is applicable to systems whose Hilbert space is infinite dimensional. Assuming particle systems, we construct the grand-canonical TPQ (gTPQ) state, which is the counterpart of the grand-canonical Gibbs state of the ensemble formulation. A single realization of the gTPQ state gives all quantities of statistical-mechanical interest, with exponentially small probability of error. This formulation not only sheds new light on quantum statistical mechanics but also is useful for practical computations. As an illustration, we apply it to the Hubbard model, on a one-dimensional (1D) chain and on a two-dimensional (2D) triangular lattice. For the 1D chain, our results agree well with the exact solutions over wide ranges of temperature, chemical potential, and the on-site interaction. For the 2D triangular lattice, for which exact results are unknown, we obtain reliable results over a wide range of temperature. We also find that finite-size effects are much smaller in the gTPQ state than in the canonical TPQ state. This also shows that in the ensemble formulation the grand-canonical Gibbs state of a finite-size system simulates an infinite system much better than the canonical Gibbs state.

      8. Capacities of noiseless quantum channels for massive indistinguishable particles: Bosons versus fermions

        SciTech Connect

        Sen, Aditi; Sen, Ujjwal; Gromek, Bartosz; Lewenstein, Maciej

        2007-02-15

        We consider information transmission through a noiseless quantum channel, where the information is encoded into massive indistinguishable particles: bosons or fermions. We study the situation in which the particles are noninteracting. The encoding input states obey a set of physically motivated constraints on the mean values of the energy and particle number. In such a case, the determination of both classical and quantum capacity reduces to a constrained maximization of entropy. In the case of noninteracting bosons, signatures of Bose-Einstein condensation can be observed in the behavior of the capacity. A major motivation for these considerations is to compare the information-carrying capacities of channels that carry bosons with those that carry fermions. We show analytically that fermions generally provide higher channel capacity, i.e., they are better suited for transferring bits as well as qubits, in comparison to bosons. This holds for a large range of power-law potentials, and for moderate to high temperatures. Numerical simulations seem to indicate that the result holds for all temperatures. Also, we consider the low-temperature behavior for the three-dimensional box and harmonic trap, and again we show that the fermionic capacity is higher than the bosonic one for sufficiently low temperatures.

      9. Cosmic rays and the birth of particle physics

        NASA Astrophysics Data System (ADS)

        Friedlander, Michael

        2013-02-01

        Twenty years after the discovery of cosmic rays, the methods of research and resulting discoveries were dramatically changed by the introduction of experimental methods that made visible the passage of individual particles. Between 1932 and 1955, tracks of cosmic rays were found in cloud chambers and special photographic emulsions. From measurements of the ionization produced along these tracks, the mass, charge and energy of a single relativistic particle could be determined. The dynamics of decays and collisions could be analyzed. Positrons and then electron-positron pairs were discovered, followed by muons and pions and then the inhabitants of the 'particle zoo'. Fundamental concepts were challenged. From the mid- 1950s, larger accelerators began to produce many of the 'new' particles, displacing cosmic rays from their prime role in particle studies. But without the initial discoveries in cosmic rays, there might well not be the modern industrial-scale particle physics research.

      10. 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).

      11. Quantum algorithm for obtaining the eigenstates of a physical system

        NASA Astrophysics Data System (ADS)

        Wang, Hefeng

        2016-05-01

        We propose a quantum algorithm for solving the following problem: given the Hamiltonian of a physical system and one of its eigenvalues, how do we obtain the corresponding eigenstate? The algorithm is based on the resonance phenomenon. For a probe qubit coupled to a quantum system, the system exhibits resonance dynamics when the frequency of the probe qubit matches a transition frequency in the system. Therefore the system can be guided to evolve to the eigenstate with a known eigenvalue by inducing the resonance between the probe qubit and a designed transition in the system. This algorithm can also be used to obtain the energy spectrum of a physical system and can achieve even quadratic speedup over the phase estimation algorithm.

      12. 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.

      13. 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…

      14. 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.

      15. 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.

      16. Quantum radiation produced by a uniformly accelerating charged particle in thermal random motion

        NASA Astrophysics Data System (ADS)

        Oshita, Naritaka; Yamamoto, Kazuhiro; Zhang, Sen

        2016-04-01

        We investigate the properties of quantum radiation produced by a uniformly accelerating charged particle undergoing thermal random motion, which originates from the coupling to the vacuum fluctuations of the electromagnetic field. Because the thermal random motion is regarded to result from the Unruh effect, the quantum radiation might give us hints of the Unruh effect. The energy flux of the quantum radiation is negative and smaller than that of Larmor radiation by one order in a /m , where a is the constant acceleration and m is the mass of the particle. Thus, the quantum radiation appears to be a suppression of the classical Larmor radiation. The quantum interference effect plays an important role in this unique signature. The results are consistent with the predictions of a model consisting of a particle coupled to a massless scalar field as well as those of the previous studies on the quantum effect on the Larmor radiation.

      17. 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.

      18. Physical characterization of quantum devices from nonlocal correlations

        NASA Astrophysics Data System (ADS)

        Bancal, Jean-Daniel; Navascués, Miguel; Scarani, Valerio; Vértesi, Tamás; Yang, Tzyh Haur

        2015-02-01

        In the device-independent approach to quantum information theory, quantum systems are regarded as black boxes that, given an input (the measurement setting), return an output (the measurement result). These boxes are then treated regardless of their actual internal working. In this paper we develop swap, a theoretical concept that, in combination with the tool of semidefinite methods for the characterization of quantum correlations, allows us to estimate physical properties of the black boxes from the observed measurement statistics. We find that the swap tool provides bounds orders of magnitude better than previously known techniques (e.g., for a Clauser-Horne-Shimony-Holt violation larger than 2.57, swap predicts a singlet fidelity greater than 70 % ). This method also allows us to deal with hitherto intractable cases such as robust device-independent self-testing of nonmaximally entangled two-qutrit states in the Collins-Gisin-Linden-Massar-Popescu scenario (for which Jordan's lemma does not apply) and the device-independent certification of entangled measurements. We further apply the swap method to relate nonlocal correlations to work extraction and quantum dimensionality, hence demonstrating that this tool can be used to study a wide variety of properties relying on the sole knowledge of accessible statistics.

      19. Hadron Physics from Superconformal Quantum Mechanics and Its Light-Front Holographic Embedding

        NASA Astrophysics Data System (ADS)

        de Téramond, Guy F.

        2016-06-01

        The complex nonperturbative color-confining dynamics of QCD is well captured in a semiclassical effective theory based on superconformal quantum mechanics and its extension to the light-front. I describe here how this new approach to hadron physics incorporates confinement, the appearance of nearly massless pseudoscalar particles, and Regge spectroscopy consistent with experiment. It also gives remarkable connections between the meson and baryon spectrum across the light and heavy-light hadron spectrum. I also briefly discuss how higher spin states are consistently described in this framework by the holographic embedding of the superconformal theory in a higher dimensional semiclassical gravity theory.

      20. A Survey of Physical Principles Attempting to Define Quantum Mechanics

        NASA Astrophysics Data System (ADS)

        Oas, Gary; Acacio de Barros, J.

        Quantum mechanics, one of the most successful theories in the history of science, was created to account for physical systems not describable by classical physics. Though it is consistent with all experiments conducted thus far, many of its core concepts (amplitudes, global phases, etc.) can not be directly accessed and its interpretation is still the subject of intense debate, more than 100 years since it was introduced. So, a fundamental question is why this particular mathematical model is the one that nature chooses, if indeed it is the correct model. In the past two decades there has been a renewed effort to determine what physical or informational principles define quantum mechanics. In this chapter, recent attempts at establishing reasonable physical principles are reviewed and their degree of success is tabulated. An alternative approach using joint quasi-probability distributions is shown to provide a common basis of representing most of the proposed principles. It is argued that having a common representation of the principles can provide intuition and guidance to relate current principles or advance new principles. The current state of affairs, along with some alternative views are discussed.

      1. 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.

      2. 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

      3. Implications of cosmological observables for particle physics: an overview

        NASA Astrophysics Data System (ADS)

        Wong, Yvonne Y. Y.

        2016-05-01

        I review how precision data from observations of the cosmic microwave background anisotropies and the large-scale structure distribution can be used to probe particle physics. Some examples are the absolute neutrino mass scale, dark radiation, light sterile neutrinos, QCD axions, WIMP annihilation, and dark sector interactions.

      4. 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.

      5. 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.

      6. Deep inelastic scaling in nuclear and particle physics

        SciTech Connect

        West, G.B.

        1988-01-01

        These lectures are intended to be a pedagogical introduction to some of the ideas and concepts concerning scaling phenomena which arise in nuclear and particle physics. Topics discussed are: classical scaling and dimensional analysis; non-relativistic treatment; dynamics and scaling; y-scaling; and relativistic treatment (QCD). 22 refs., 16 figs. (LSP)

      7. 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. PMID:20431257

      8. 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

      9. 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.

      10. Current experiments in elementary particle physics, revision 1-85

        NASA Astrophysics Data System (ADS)

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

      11. 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.

      12. 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.

      13. 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.

      14. Dipolar Physics in an Erbium Quantum Gas Microscope

        NASA Astrophysics Data System (ADS)

        Hebert, Anne; Krahn, Aaron; Phelps, Gregory; Dickerson, Susannah; Greiner, Markus; Erbium Lab Team

        2016-05-01

        Erbium offers exciting possibilities for extending the single-site imaging work of current quantum gas microscopes. With a magnetic dipole moment of 7μB, the dipole-dipole interaction of erbium is 50 times that of alkali atoms. The long-range and anisotropic nature of the dipole interaction adds richness to the short-range interactions that dominate the physics of the ground-state alkali atoms commonly used in ultracold experiments today. Erbium has several abundant isotopes, giving the added flexibility of studying both bosonic and fermionic systems. We present proposed avenues of research for the dipolar microscope being developed, including studies of magnetism, the Einstein-de Haas effect, and quantum phase transitions with fractional filling factors.

      15. Edward A. Bouchet Award Talk: Nuclear and Particle Physics Research

        NASA Astrophysics Data System (ADS)

        Baker, Oliver K.

        2002-04-01

        Nuclear and particle physics research at Historically Black Colleges and Universities (HBCU's) can be invigorating and rewarding for those doing the work at these institutions. One example of this is given by the work of students, staff, and faculty at Hampton University and its collaborating HBCU's at Jefferson Lab (JLAB) and ATLAS at the Large Hadron Collider (LHC). The nuclear physics research for the past decade has been focussed on the study of hadronic systems with strangeness degrees of freedom using electromagnetic probes at JLAB. The particle physics research is the building up of the detectors and development of the software needed to study electroweak physics at the TeV mass scale using ATLAS at the LHC when it is completed (around 2006). The speaker will present an overview of the physics results from these studies and their implications, the detectors used and their construction, and the impact that this work has had on young nuclear and particle physicists who have contributed to these efforts.

      16. Stochastic vacuum of quantum chromodynamics as an environment for color particles

        NASA Astrophysics Data System (ADS)

        Kuvshinov, V.; Bagashov, E.

        2016-05-01

        The behavior of quarks is described within approaches used in quantum mechanics and related disciplines (quantum optics and quantum theory of information). The stochastic vacuum of quantum chromodynamics is treated as an environment (closed pool) for color particles (quarks). Their interaction results in a loss of information on the quark color state and consequently in the impossibility of observing it (the confinement of quarks). The processes are described using quantities of the quantum theory of information, such as von Neumann entropy, fidelity, and purity.

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

        SciTech Connect

        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.

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

        PubMed

        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. PMID:26465456

      19. 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. PMID:27253377

      20. 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

      1. 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. PMID:26520491

      2. 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

      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. 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

      5. Quantum lattice-gas model for the many-particle Schr{umlt o}dinger equation in d dimensions

        SciTech Connect

        Boghosian, B.M.; Taylor, W. IV

        1998-01-01

        We consider a general class of discrete unitary dynamical models on the lattice. We show that generically such models give rise to a wave function satisfying a Schr{umlt o}dinger equation in the continuum limit, in any number of dimensions. There is a simple mathematical relationship between the mass of the Schr{umlt o}dinger particle and the eigenvalues of a unitary matrix describing the local evolution of the model. Second quantized versions of these unitary models can be defined, describing in the continuum limit the evolution of a nonrelativistic quantum many-body theory. An arbitrary potential is easily incorporated into these systems. The models we describe fall in the class of quantum lattice-gas automata and can be implemented on a quantum computer with a speedup exponential in the number of particles in the system. This gives an efficient algorithm for simulating general nonrelativistic interacting quantum many-body systems on a quantum computer. {copyright} {ital 1998} {ital The American Physical Society}

      6. Measurement-driven reconstruction of many-particle quantum processes by semidefinite programming with application to photosynthetic light harvesting

        NASA Astrophysics Data System (ADS)

        Foley, Jonathan J., IV; Mazziotti, David A.

        2012-07-01

        Quantum measurements provide a trove of information about a quantum system or process without solution of the Schrödnger equation, and in principle, the associated density matrix is a function of these measurements. Inversion of the measurements can produce an estimate of the density matrix, but this estimate may be unphysical, especially when the measurements are noisy or incomplete. We develop a general approach based on semidefinite programming [D. A. Mazziotti, Phys. Rev. Lett.PRLTAO0031-900710.1103/PhysRevLett.106.083001 106, 083001 (2011)] for reconstructing the density matrix from quantum measurements which leads naturally to nonnegative solutions, a critical attribute of physically realistic solutions. We discuss the use of this methodology for reconstructing p-particle reduced density matrices (p-RDMs) of N-particle systems where additional semidefinite constraints, known as N-representability conditions, are essential because they ensure that the p-RDM represents an N-particle system. Special attention is given to the N-representability conditions for the experimentally important cases where p=1 or 2. We apply the methodology to reconstructing the time-dependent quantum process of exciton transfer in a photosynthetic light-harvesting complex.

      7. Parameter Estimation of Fractional-Order Chaotic Systems by Using Quantum Parallel Particle Swarm Optimization Algorithm

        PubMed Central

        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. PMID:25603158

      8. 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. PMID:25603158

      9. 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.

      10. 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.

      11. Physics of molecular machines operated by a particle flux

        NASA Astrophysics Data System (ADS)

        Perez-Carrasco, R.; Sancho, J. M.

        2012-11-01

        Here we present a basic theoretical analysis of molecular machines (turbines) operating with particle fluxes either such as motor or pump regimes. Our focus is on the physical observables: velocity, flux, power and efficiency. We will show that thermal fluctuations are essential to understand its behaviour changing completely the deterministic predictions. Thermal fluctuations introduce a finite domain where no useful output can be extracted from this device due to particle leakage. Furthermore, the maximum of efficiency does not follow the deterministic analysis. Our results also present a bottom line to address the study of these devices in more complex models and to inspire new experiments in this type of machines.

      12. 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.

      13. Strong subadditivity inequality for quantum entropies and four-particle entanglement

        NASA Astrophysics Data System (ADS)

        Biswas, Asoka; Agarwal, G. S.

        2003-11-01

        The strong subadditivity inequality for a three-particle composite system is an important inequality in quantum information theory which can be studied via a four-particle entangled state. We use two three-level atoms in Λ configuration interacting with a two-mode cavity and the Raman adiabatic passage technique for the production of the four-particle entangled state. Using this four-particle entanglement, we study various aspects of the strong subadditivity inequality.

      14. 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.

      15. Fundamental Constants as Monitors of Particle Physics and Dark Energy

        NASA Astrophysics Data System (ADS)

        Thompson, Rodger

        2016-03-01

        This contribution considers the constraints on particle physics and dark energy parameter space imposed by the astronomical observational constraints on the variation of the proton to electron mass ratio μ and the fine structure constant α. These constraints impose limits on the temporal variation of these parameters on a time scale greater than half the age of the universe, a time scale inaccessible by laboratory facilities such as the Large Hadron Collider. The limits on the variance of μ and α constrain combinations of the QCD Scale, the Higgs VEV and the Yukawa coupling on the particle physics side and a combination of the temporal variation of rolling scalar field and its coupling to the constants on the dark energy side.

      16. 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.

      17. 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.

      18. 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.

      19. Particle physics catalysis of thermal big bang nucleosynthesis.

        PubMed

        Pospelov, Maxim

        2007-06-01

        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. PMID:17677895

      20. Nuclear and particle physics aspects of hyperon and antinucleon interactions

        SciTech Connect

        Dover, C.B.

        1984-01-01

        A discussion is given of hyperon (Y) and antinucleon (anti N) interactions with nucleons and nuclei, emphasizing some of the future prospects for nuclear structure and elementary particle physics studies at LEAR or a future kaon factory. The topics addressed include: (1) production and decay of strange dibaryons; (2) spectroscopy of strangeness S = -2 many body systems; (3) N anti N annihilation mechanisms; and (4) inelastic anti N-nucleus scattering and spin-flip excitations in nuclei. 36 references.

      1. 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)

      2. Silicon Detectors-Tools for Discovery in Particle Physics

        SciTech Connect

        Krammer, Manfred

        2009-07-07

        Since the first application of Silicon strip detectors in high energy physics in the early 1980ies these detectors have enabled the experiments to perform new challenging measurements. With these devices it became possible to determine the decay lengths of heavy quarks, for example in the fixed target experiment NA11 at CERN. In this experiment Silicon tracking detectors were used for the identification of particles containing a c-quark. Later on, the experiments at the Large Electron Positron collider at CERN used already larger and sophisticated assemblies of Silicon detectors to identify and study particles containing the b-quark. A very important contribution to the discovery of the last of the six quarks, the top quark, has been made by even larger Silicon vertex detectors inside the experiments CDF and D0 at Fermilab. Nowadays a mature detector technology, the use of Silicon detectors is no longer restricted to the vertex regions of collider experiments. The two multipurpose experiments ATLAS and CMS at the Large Hadron Collider at CERN contain large tracking detectors made of Silicon. The largest is the CMS Inner Tracker consisting of 200 m{sup 2} of Silicon sensor area. These detectors will be very important for a possible discovery of the Higgs boson or of Super Symmetric particles. This paper explains the first applications of Silicon sensors in particle physics and describes the continuous development of this technology up to the construction of the state of the art Silicon detector of CMS.

      3. The 5th Generation model of Particle Physics

        NASA Astrophysics Data System (ADS)

        Lach, Theodore

        2009-05-01

        The Standard model of Particle Physics is able to account for all known HEP phenomenon, yet it is not able to predict the masses of the quarks or leptons nor can it explain why they have their respective values. The Checker Board Model (CBM) predicts that there are 5 generation of quarks and leptons and shows a pattern to those masses, namely each three quarks or leptons (within adjacent generations or within a generation) are related to each other by a geometric mean relationship. A 2D structure of the nucleus can be imaged as 2D plate spinning on its axis, it would for all practical circumstances appear to be a 3D object. The masses of the hypothesized ``up'' and ``dn'' quarks determined by the CBM are 237.31 MeV and 42.392 MeV respectively. These new quarks in addition to a lepton of 7.4 MeV make up one of the missing generations. The details of this new particle physics model can be found at the web site: checkerboard.dnsalias.net. The only areas were this theory conflicts with existing dogma is in the value of the mass of the Top quark. The particle found at Fermi Lab must be some sort of composite particle containing Top quarks.

      4. 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.

      5. Future large scale accelerator projects for particle physics

        NASA Astrophysics Data System (ADS)

        Aleksan, R.

        2013-12-01

        The discovery of a new particle, the properties of which are compatible with the expected Brout-Englert-Higgs scalar field in the Standard Model (SM), is the starting point of an intense program for studying its couplings. With this particle, all the components of the SM have now been unraveled. Yet, the existence of dark matter, baryon asymmetry of the Universe and neutrino mass call for new physics at an energy scale, which is not determined so far. Therefore, new large scale accelerators are needed to investigate these mysteries through ultra-high precision measurements and/or the exploration of higher energy frontiers. In the following, we discuss the various accelerator projects aimed at the achievement of the above objectives. The physics reach of these facilities will be briefly described as well as their main technical features and related challenges, highlighting the importance of accelerator R&D not only for the benefit of particle physics but also for other fields of research, and more generally for the society.

      6. Object Oriented Design and the Standard Model of particle physics

        NASA Astrophysics Data System (ADS)

        Lipovaca, Samir

        2007-04-01

        Inspired by the computer as both tool and metaphor, a new path emerges toward understanding life, physics, and existence. The path leads throughout all of nature, from the interior of cells to inside black holes. This view of science is based on the idea that information is the ultimate ``substance'' from which all things are made. Exploring this view, we will focus on Object - Oriented (OO) design as one of the most important designs in software development. The OO design views the world as composed of objects with well defined properties. The dynamics is pictured as interactions among objects. Interactions are mediated by messages that objects exchange with each other. This description closely resembles the view of the elementary particles world created by the Standard Model of particle physics. The object model (OM) provides a theoretical foundation upon which the OO design is built. The OM is based on the principles of abstraction, encapsulation, modularity and hierarchy. We will show that the Standard Model of particle physics follows the OM principles.

      7. 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

      8. Quantum entanglement of identical particles by standard information-theoretic notions.

        PubMed

        Lo Franco, Rosario; Compagno, Giuseppe

        2016-01-01

        Quantum entanglement of identical particles is essential in quantum information theory. Yet, its correct determination remains an open issue hindering the general understanding and exploitation of many-particle systems. Operator-based methods have been developed that attempt to overcome the issue. Here we introduce a state-based method which, as second quantization, does not label identical particles and presents conceptual and technical advances compared to the previous ones. It establishes the quantitative role played by arbitrary wave function overlaps, local measurements and particle nature (bosons or fermions) in assessing entanglement by notions commonly used in quantum information theory for distinguishable particles, like partial trace. Our approach furthermore shows that bringing identical particles into the same spatial location functions as an entangling gate, providing fundamental theoretical support to recent experimental observations with ultracold atoms. These results pave the way to set and interpret experiments for utilizing quantum correlations in realistic scenarios where overlap of particles can count, as in Bose-Einstein condensates, quantum dots and biological molecular aggregates. PMID:26857475

      9. Quantum entanglement of identical particles by standard information-theoretic notions

        NASA Astrophysics Data System (ADS)

        Lo Franco, Rosario; Compagno, Giuseppe

        2016-02-01

        Quantum entanglement of identical particles is essential in quantum information theory. Yet, its correct determination remains an open issue hindering the general understanding and exploitation of many-particle systems. Operator-based methods have been developed that attempt to overcome the issue. Here we introduce a state-based method which, as second quantization, does not label identical particles and presents conceptual and technical advances compared to the previous ones. It establishes the quantitative role played by arbitrary wave function overlaps, local measurements and particle nature (bosons or fermions) in assessing entanglement by notions commonly used in quantum information theory for distinguishable particles, like partial trace. Our approach furthermore shows that bringing identical particles into the same spatial location functions as an entangling gate, providing fundamental theoretical support to recent experimental observations with ultracold atoms. These results pave the way to set and interpret experiments for utilizing quantum correlations in realistic scenarios where overlap of particles can count, as in Bose-Einstein condensates, quantum dots and biological molecular aggregates.

      10. Quantum entanglement of identical particles by standard information-theoretic notions

        PubMed Central

        Lo Franco, Rosario; Compagno, Giuseppe

        2016-01-01

        Quantum entanglement of identical particles is essential in quantum information theory. Yet, its correct determination remains an open issue hindering the general understanding and exploitation of many-particle systems. Operator-based methods have been developed that attempt to overcome the issue. Here we introduce a state-based method which, as second quantization, does not label identical particles and presents conceptual and technical advances compared to the previous ones. It establishes the quantitative role played by arbitrary wave function overlaps, local measurements and particle nature (bosons or fermions) in assessing entanglement by notions commonly used in quantum information theory for distinguishable particles, like partial trace. Our approach furthermore shows that bringing identical particles into the same spatial location functions as an entangling gate, providing fundamental theoretical support to recent experimental observations with ultracold atoms. These results pave the way to set and interpret experiments for utilizing quantum correlations in realistic scenarios where overlap of particles can count, as in Bose-Einstein condensates, quantum dots and biological molecular aggregates. PMID:26857475

      11. 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.

      12. 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.

      13. 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.

      14. 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.

      15. 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

      16. Research accomplishments and future goals in particle physics

        NASA Astrophysics Data System (ADS)

        1994-06-01

        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. Boston University is active in seven principal areas: (1) Task A: Colliding Beams - physics of e(sup +)e(sup -) and (anti p)p collisions; (2) Task C: MACRO Experiment - search for magnetic monopoles and study of cosmic rays; (3) Task D: Proton Decay - search for nucleon instability and study of neutrino interactions; (4) Tasks E, J, and N: Particle Theory - theoretical high energy particle physics, including two Outstanding Junior Investigator awards; (5) Task F: Muon G-2 - measurement of the anomalous magnetic moment of the muon; (6) Task K: SSCintcal - calorimetry for the GEM Experiment; (7) Task L: Muon Detectors for the GEM Experiment. The body of the proposal is devoted to detailed discussions of each of the tasks. The total budget request for the program appears in a summary chapter that includes a general budget discussion and individual budget requests and explanations for each of the tasks.

      17. Quantum Correlations of Two Relativistic Spin-{1}/{2} Particles Under Noisy Channels

        NASA Astrophysics Data System (ADS)

        Mahdian, M.; Mojaveri, B.; Dehghani, A.; Makaremi, T.

        2016-02-01

        We study the quantum correlation dynamics of bipartite spin-{1}/{2} density matrices for two particles under Wigner rotations induced by Lorentz transformations which is transmitted through noisy channels. We compare quantum entanglement, geometric discord(GD), and quantum discord (QD) for bipartite relativistic spin-{1}/{2} states under noisy channels. We find out QD and GD tend to death asymptotically but a sudden change in the decay rate of the entanglement occurs under noisy channels. Also, bipartite relativistic spin density matrices are considered as a quantum channel for teleportation one-qubit state under the influence of depolarizing noise and compare fidelity for various velocities of observers.

      18. The XXth International Workshop High Energy Physics and Quantum Field Theory

        NASA Astrophysics Data System (ADS)

        The Workshop continues a series of workshops started by the Skobeltsyn Institute of Nuclear Physics of Lomonosov Moscow State University (SINP MSU) in 1985 and conceived with the purpose of presenting topics of current interest and providing a stimulating environment for scientific discussion on new developments in theoretical and experimental high energy physics and physical programs for future colliders. Traditionally the list of workshop attendees includes a great number of active young scientists and students from Russia and other countries. This year Workshop is organized jointly by the SINP MSU and the Southern Federal University (SFedU) and will take place in the holiday hotel "Luchezarniy" (Effulgent) situated on the Black Sea shore in a picturesque natural park in the suburb of the largest Russian resort city Sochi - the host city of the XXII Olympic Winter Games to be held in 2014. The main topics to be covered are: Experimental results from the LHC. Tevatron summary: the status of the Standard Model and the boundaries on BSM physics. Future physics at Linear Colliders and super B-factories. Extensions of the Standard Model and their phenomenological consequences at the LHC and Linear Colliders: SUSY extensions of the Standard Model; particle interactions in space-time with extra dimensions; strings, quantum groups and new ideas from modern algebra and geometry. Higher order corrections and resummations for collider phenomenology. Automatic calculations of Feynman diagrams and Monte Carlo simulations. LHC/LC and astroparticle/cosmology connections. Modern nuclear physics and relativistic nucleous-nucleous collisions.

      19. Life at the interface of particle physics and string theory

        NASA Astrophysics Data System (ADS)

        Schellekens, A. N.

        2013-10-01

        If the results of the first LHC run are not betraying us, many decades of particle physics are culminating in a complete and consistent theory for all nongravitational physics: the standard model. But despite this monumental achievement there is a clear sense of disappointment: many questions remain unanswered. Remarkably, most unanswered questions could just be environmental, and disturbingly to some the existence of life may depend on that environment. Meanwhile there has been increasing evidence that the seemingly ideal candidate for answering these questions, string theory, gives an answer few people initially expected: a large “landscape” of possibilities that can be realized in a multiverse and populated by eternal inflation. At the interface of “bottom-up” and “top-down” physics, a discussion of anthropic arguments becomes unavoidable. Developments in this area are reviewed, focusing especially on the last decade.

      20. 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.

      1. Physical interactions of charged particles for radiotherapy and space applications.

        PubMed

        Zeitlin, Cary

        2012-11-01

        In this paper, the basic physics by which energetic charged particles deposit energy in matter is reviewed. Energetic charged particles are used for radiotherapy and are encountered in spaceflight, where they pose a health risk to astronauts. They interact with matter through nuclear and electromagnetic forces. Deposition of energy occurs mostly along the trajectory of the incoming particle, but depending on the type of incident particle and its energy, there is some nonzero probability for energy deposition relatively far from the nominal trajectory, either due to long-ranged knock-on electrons (sometimes called delta rays) or from the products of nuclear fragmentation, including neutrons. In the therapy setting, dose localization is of paramount importance, and the deposition of energy outside nominal treatment volumes complicates planning and increases the risk of secondary cancers as well as noncancer effects in normal tissue. Statistical effects are also important and will be discussed. In contrast to radiation therapy patients, astronauts in space receive comparatively small whole-body radiation doses from energetic charged particles and associated secondary radiation. A unique aspect of space radiation exposures is the high-energy heavy-ion component of the dose. This is not present in terrestrial exposures except in carbon-ion radiotherapy. Designers of space missions must limit exposures to keep risk within acceptable limits. These limits are, at present, defined for low-Earth orbit, but not for deep-space missions outside the geomagnetosphere. Most of the uncertainty in risk assessment for such missions comes from the lack of understanding of the biological effectiveness of the heavy-ion component, with a smaller component due to uncertainties in transport physics and dosimetry. These same uncertainties are also critical in the therapy setting. PMID:23032883

      2. Quantum tunneling of massive spin-1 particles from non-stationary metrics

        NASA Astrophysics Data System (ADS)

        Sakalli, I.; Övgün, A.

        2016-01-01

        We focus on the HR of massive vector (spin-1) particles tunneling from Schwarzschild BH expressed in the Kruskal-Szekeres and dynamic Lemaitre coordinates. Using the Proca equation together with the Hamilton-Jacobi and the WKB methods, we show that the tunneling rate, and its consequence Hawking temperature are well recovered by the quantum tunneling of the massive vector particles.

      3. 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.

      4. 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. PMID:26613435

      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. 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

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

        NASA Astrophysics Data System (ADS)

        Morimae, Tomoyuki

        2011-04-01

        In the framework of the computational tensor network [Phys. Rev. Lett.PRLTAO0031-900710.1103/PhysRevLett.98.220503 98, 220503 (2007)], the quantum computation is performed in a virtual linear space called the correlation space. It was recently shown [Phys. Rev. Lett.PRLTAO0031-900710.1103/PhysRevLett.103.050503 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 [Phys. Rev. Lett.PRLTAO0031-900710.1103/PhysRevLett.103.050503 103, 050503 (2009)], which also works to upload, the proposed uploading method has several advantages.

      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. Ad Hoc Physical Hilbert Spaces in Quantum Mechanics

        NASA Astrophysics Data System (ADS)

        Fernández, Francisco M.; Garcia, Javier; Semorádová, Iveta; Znojil, Miloslav

        2015-12-01

        The overall principles of what is now widely known as PT-symmetric quantum mechanics are listed, explained and illustrated via a few examples. In particular, models based on an elementary local interaction V(x) are discussed as motivated by the naturally emergent possibility of an efficient regularization of an otherwise unacceptable presence of a strongly singular repulsive core in the origin. The emphasis is put on the constructive aspects of the models. Besides the overall outline of the formalism we show how the low-lying energies of bound states may be found in closed form in certain dynamical regimes. Finally, once these energies are found real we explain that in spite of a manifest non-Hermiticity of the Hamiltonian the time-evolution of the system becomes unitary in a properly amended physical Hilbert space.

      10. Local State and Sector Theory in Local Quantum Physics

        NASA Astrophysics Data System (ADS)

        Ojima, Izumi; Okamura, Kazuya; Saigo, Hayato

        2016-04-01

        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.

      11. Method of Improving the Teaching of Particle Physics in a Noncalculus Course of Physics

        NASA Astrophysics Data System (ADS)

        Chen, Robert L. W.

        The Klein Gordon equation-which describes mesons-can be reformulated to suit students who have no calculus background. The method is arrived at from a review and a reinterpretation of the mechanics of small oscillations. It may serve as a model for the design of new instructions for other areas of particle physics.

      12. Hydrodynamics of the Physical Vacuum: I. Scalar Quantum Sector

        NASA Astrophysics Data System (ADS)

        Sbitnev, Valeriy I.

        2016-05-01

        Physical vacuum is a special superfluid medium. Its motion is described by the Navier-Stokes equation having two slightly modified terms that relate to internal forces. They are the pressure gradient and the dissipation force because of viscosity. The modifications are as follows: (a) the pressure gradient contains an added term describing the pressure multiplied by the entropy gradient; (b) time-averaged viscosity is zero, but its variance is not zero. Owing to these modifications, the Navier-Stokes equation can be reduced to the Schrödinger equation describing behavior of a particle into the vacuum, which looks like a superfluid medium populated by enormous amount of virtual particle-antiparticle pairs.

      13. Major detectors in elementary-particle physics. [Portfolio

        SciTech Connect

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

        1983-03-01

        With the 1983 issue of LBL-91 we introduce a supplement - a folio of descriptions of the world's major elementary particle physics detectors. Modern high energy physics usually involves the use of massive, costly, carefully engineered, large solid angle detectors. These detectors require a long lead time for construction, are often integrated with an accelerator, accumulate data over many years, and are in reality a combination of numerous subsystems. As was the case with bubble chambers, many experiments are performed with the same data, or with data taken after relatively minor changes or additions to the detector configuration. These experiments are often reported in journals whose space limitations make repeated full descriptions of the detector impossible. The detailed properties and performance of the detector are usually described in a fragmented series of papers in more specialized, technologically oriented journals. New additions are often not well documented. Several detectors often make similar measurements and physicists want to make quick comparisons of their respective capabilities. Designers of new large detectors and even of smaller experiments need to know what already exists and what performance has been achieved. To aid the physics community, the Particle Data Group has produced this brief folio of the world's major large detectors. This first edition has some notable omissions: in particular, the bubble chambers and any associated spectrometers, and the still somewhat tentative LEP, SLC, and TRISTAN detectors.

      14. 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.

      15. Physics of leptoquarks in precision experiments and at particle colliders

        NASA Astrophysics Data System (ADS)

        Doršner, I.; Fajfer, S.; Greljo, A.; Kamenik, J. F.; Košnik, N.

        2016-06-01

        We present a comprehensive review of physics effects generated by leptoquarks (LQs), i.e., hypothetical particles that can turn quarks into leptons and vice versa, of either scalar or vector nature. These considerations include discussion of possible completions of the Standard Model that contain LQ fields. The main focus of the review is on those LQ scenarios that are not problematic with regard to proton stability. We accordingly concentrate on the phenomenology of light leptoquarks that is relevant for precision experiments and particle colliders. Important constraints on LQ interactions with matter are derived from precision low-energy observables such as electric dipole moments, (g - 2) of charged leptons, atomic parity violation, neutral meson mixing, Kaon, B, and D meson decays, etc. We provide a general analysis of indirect constraints on the strength of LQ interactions with the quarks and leptons to make statements that are as model independent as possible. We address complementary constraints that originate from electroweak precision measurements, top, and Higgs physics. The Higgs physics analysis we present covers not only the most recent but also expected results from the Large Hadron Collider (LHC). We finally discuss direct LQ searches. Current experimental situation is summarized and self-consistency of assumptions that go into existing accelerator-based searches is discussed. A progress in making next-to-leading order predictions for both pair and single LQ productions at colliders is also outlined.

      16. Energetic Particle Instrumentation for Future Space Physics Missions

        NASA Astrophysics Data System (ADS)

        Perry, C. H.; Griffin, D. K.; Dunlop, M. W.; Davies, J. A.; Hapgood, M. A.

        2009-04-01

        Collisionless plasmas frequently exhibit strong fluxes of electrons and ions at energies well above the mean plasma energy. These suprathermal particles play an important role in the identification and interpretation of the fundamental properties and physical processes within space plasmas. Investigations of these energetic populations require both good angular and temporal resolution measurements. Large geometric factors and fast electronics are vital to ensure adequate sampling of the tail of the particle distribution. We present the status of the energetic particle instrument development activity that is currently underway at the Rutherford Appleton Laboratory. This is in preparation for both the proposed HEP instrument for Cross-Scale mission, which is currently undergoing assessment for the ESA's Cosmic Vision programme, and the IEPS instrument for the Chinese KuaFu mission. The activities are based on the heritage of instruments already successfully flown on the NASA/Polar and ESA/Cluster spacecraft. The design consists of a simple ‘pin-hole' aperture and segmented silicon solid state detector array capable of measuring energetic particle distributions in the range 30-1000 keV. Key features of the activities include the development of 1) a modular mechanical design that can easily support different spacecraft accommodation constraints and scientific requirements, 2) combined detector configurations for ions and electrons, and 3) multi-channel hybrid ASICs for the sensor electronics which is crucial for low mass and power.

      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. 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

      20. A one-dimensional lattice model for a quantum mechanical free particle

        NASA Astrophysics Data System (ADS)

        de La Torre, A. C.; Daleo, A.

        2000-01-01

        Two types of particles, A and B with their corresponding antiparticles, are defined in a onedimensional cyclic lattice with an odd number of sites. In each step of time evolution, each particle acts as a source for the polarization field of the other type of particle with nonlocal action but with an effect decreasing with the distance: A to \\cdots bar BBbar BBbar B \\cdots ;B to \\cdots Abar AAbar AA \\cdots . It is shown that the combined distribution of these particles obeys the time evolution of a free particle as given by quantum mechanics.

      1. UCLA Particle and Nuclear Physics Research Group, 1993 progress report

        SciTech Connect

        Nefkens, B.M.K.; Clajus, M.; Price, J.W.; Tippens, W.B.; White, D.B.

        1993-09-01

        The research programs of the UCLA Particle and Nuclear Physics Research Group, the research objectives, results of experiments, the continuing activities and new initiatives are presented. The primary goal of the research is to test the symmetries and invariances of particle/nuclear physics with special emphasis on investigating charge symmetry, isospin invariance, charge conjugation, and CP. Another important part of our work is baryon spectroscopy, which is the determination of the properties (mass, width, decay modes, etc.) of particles and resonances. We also measure some basic properties of light nuclei, for example the hadronic radii of {sup 3}H and {sup 3}He. Special attention is given to the eta meson, its production using photons, electrons, {pi}{sup {plus_minus}}, and protons, and its rare and not-so-rare decays. In Section 1, the physics motivation of our research is outlined. Section 2 provides a summary of the research projects. The status of each program is given in Section 3. We discuss the various experimental techniques used, the results obtained, and we outline the plans for the continuing and the new research. Details are presented of new research that is made possible by the use of the Crystal Ball Detector, a highly segmented NaI calorimeter and spectrometer with nearly 4{pi} acceptance (it was built and used at SLAC and is to be moved to BNL). The appendix contains an update of the bibliography, conference participation, and group memos; it also indicates our share in the organization of conferences, and gives a listing of the colloquia and seminars presented by us.

      2. 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.

      3. Particle physics for everybody. [Depiction of elementary particle as known today

        SciTech Connect

        Davies, P.

        1987-12-01

        The impact of particle physics on astronomy and cosmology is discussed in a historical context. Consideration is given to the four (recognized) fundamental forces in nature: gravitation, electromagnetism, and weak and strong nuclear forces. Antimatter is discussed as well as fermions and bosons (and their subclasses) and symmetry. Various unification schemes are presented, and it is noted that, depending on the properties of the various cosmions, their gravitating power may be sufficient to halt the expansion of the universe.

      4. A guide to data in elementary particle physics

        SciTech Connect

        Yost, G.P.; Rittenberg, A.; Armstrong, B.; Ferguson, M. Jr.; Levine, B.S.; Simpson, K.H.; Trippe, T.G.; Visser, M.J.; Wagman, G.S.; Wohl, C.G.

        1986-09-01

        We present an indexed guide to experimental high energy physics literature for the years 1977 through 1985. While no actual data are included, approximately 9000 papers are indexed by Beam/Target/Momentum, Reaction/Momentum (including the final state), Particle, and Accelerator/Detector. All indices are cross-referenced via an ID to the paper's title and references in the ID/Reference/Title Index. Black marks (bleeder tabs) at the side of the page enable each section to be located quickly, using the Table of Contents on the back cover. The information presented in this guide is also publicly available on a regularly updated SLAC-SPIRES database called DATAGUIDE.

      5. 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.

      6. The relation between the quantum discord and quantum teleportation: The physical interpretation of the transition point between different quantum discord decay regimes

        NASA Astrophysics Data System (ADS)

        Roszak, K.; Cywiński, Ł.

        2015-10-01

        We study quantum teleportation via Bell-diagonal mixed states of two qubits in the context of the intrinsic properties of the quantum discord. We show that when the quantum-correlated state of the two qubits is used for quantum teleportation, the character of the teleportation efficiency changes substantially depending on the Bell-diagonal-state parameters, which can be seen when the worst-case-scenario or best-case-scenario fidelity is studied. Depending on the parameter range, one of two types of single-qubit states is hardest/easiest to teleport. The transition between these two parameter ranges coincides exactly with the transition between the range of classical correlation decay and quantum correlation decay characteristic for the evolution of the quantum discord. The correspondence provides a physical interpretation for the prominent feature of the decay of the quantum discord.

      7. The Butterfly and the Photon:. New Perspectives on Unpredictability, and the Notion of Casual Reality, in Quantum Physics

        NASA Astrophysics Data System (ADS)

        Palmer, T. N.

        2012-12-01

        This essay discusses a proposal that draws together the three great revolutionary theories of 20th Century physics: quantum theory, relativity theory and chaos theory. Motivated by the Bohmian notion of implicate order, and what in chaos theory would be described as a strange attractor, the proposal attributes special ontological significance to certain non-computable, dynamically invariant state-space geometries for the universe as a whole. Studying the phenomenon of quantum interference, it is proposed to understand quantum wave-particle duality, and indeed classical electromagnetism, in terms of particles in space time and waves on this state space geometry. Studying the EPR experiment, the acausal constraints that this invariant geometry provides on spatially distant degrees of freedom, provides a way for the underlying dynamics to be consistent with the Bell theorem, yet be relativistically covariant ("nonlocality without nonlocality"). It is suggested that the physical basis for such non-computable geometries lies in properties of gravity with the information irreversibility implied by black hole no-hair theorems being crucial. In conclusion it is proposed that quantum theory may be emergent from an extended theory of gravity which is geometric not only in space time, but also in state space. Such a notion would undermine most current attempts to "quantise gravity".

      8. 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.

      9. Model of cosmology and particle physics at an intermediate scale

        SciTech Connect

        Bastero-Gil, M.; Di Clemente, V.; King, S. F.

        2005-05-15

        We propose a model of cosmology and particle physics in which all relevant scales arise in a natural way from an intermediate string scale. We are led to assign the string scale to the intermediate scale M{sub *}{approx}10{sup 13} GeV by four independent pieces of physics: electroweak symmetry breaking; the {mu} parameter; the axion scale; and the neutrino mass scale. The model involves hybrid inflation with the waterfall field N being responsible for generating the {mu} term, the right-handed neutrino mass scale, and the Peccei-Quinn symmetry breaking scale. The large scale structure of the Universe is generated by the lightest right-handed sneutrino playing the role of a coupled curvaton. We show that the correct curvature perturbations may be successfully generated providing the lightest right-handed neutrino is weakly coupled in the seesaw mechanism, consistent with sequential dominance.

      10. The quantum universe

        NASA Astrophysics Data System (ADS)

        Hey, Anthony J. G.; Walters, Patrick

        This book provides a descriptive, popular account of quantum physics. The basic topics addressed include: waves and particles, the Heisenberg uncertainty principle, the Schroedinger equation and matter waves, atoms and nuclei, quantum tunneling, the Pauli exclusion principle and the elements, quantum cooperation and superfluids, Feynman rules, weak photons, quarks, and gluons. The applications of quantum physics to astrophyics, nuclear technology, and modern electronics are addressed.

      11. Molecular Rotation Signals: Molecule Chemistry and Particle Physics

        NASA Astrophysics Data System (ADS)

        Grabow, Jens-Uwe

        2015-06-01

        Molecules - large or small - are attractive academic resources, with numerous questions on their chemical behaviour as well as problems in fundamental physics now (or still) waiting to be answered: Targeted by high-resolution spectroscopy, a rotating molecular top can turn into a laboratory for molecule chemistry or a laboratory for particle physics. Once successfully entrained (many species - depending on size and chemical composition - have insufficient vapour pressures or are of transient nature, such that specifically designed pulsed-jet sources are required for their transfer into the gas phase or in-situ generation) into the collision-free environment of a supersonic-jet expansion, each molecular top comes with its own set of challenges, theoretically and experimentally: Multiple internal interactions are causing complicated energy level schemes and the resulting spectra will be rather difficult to predict theoretically. Experimentally, these spectra are difficult to assess and assign. With today's broad-banded chirp microwave techniques, finding and identifying such spectral features have lost their major drawback of being very time consuming for many molecules. For other molecules, the unrivalled resolution and sensitivity of the narrow-banded impulse microwave techniques provide a window to tackle - at the highest precision available to date - fundamental questions in physics, even particle physics - potentially beyond the standard model. Molecular charge distribution, properties of the chemical bond, details on internal dynamics and intermolecular interaction, the (stereo-chemical) molecular structure (including the possibility of their spatial separation) as well as potential evidence for tiny yet significant interactions encode their signature in pure molecular rotation subjected to time-domain microwave spectroscopic techniques. Ongoing exciting technical developments promise rapid progress. We present recent examples from Hannover, new directions, and

      12. 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

      13. Levy distribution in many-particle quantum systems

        SciTech Connect

        Ponomarev, A. V.; Denisov, S.; Haenggi, P.

        2010-04-15

        The Levy distribution, previously used to describe complex behavior of classical systems, is shown to characterize that of quantum many-body systems. Using two complimentary approaches, the canonical and grand-canonical formalisms, we discovered that the momentum profile of a Tonks-Girardeau gas - a one-dimensional gas of N impenetrable (hard-core) bosons-harmonically confined on a lattice at finite temperatures obeys a Levy distribution. Finally, we extend our analysis to different confinement setups and demonstrate that the tunable Levy distribution properly reproduces momentum profiles in experimentally accessible regions. Our finding allows for calibration of complex many-body quantum states by using a unique scaling exponent.

      14. 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.

      15. Phase space dynamics and control of the quantum particles associated to hypergraph states

        NASA Astrophysics Data System (ADS)

        Berec, Vesna

        2015-05-01

        As today's nanotechnology focus becomes primarily oriented toward production and manipulation of materials at the subatomic level, allowing the performance and complexity of interconnects where the device density accepts more than hundreds devices on a single chip, the manipulation of semiconductor nanostructures at the subatomic level sets its prime tasks on preserving and adequate transmission of information encoded in specified (quantum) states. The presented study employs the quantum communication protocol based on the hypergraph network model where the numerical solutions of equations of motion of quantum particles are associated to vertices (assembled with device chip), which follow specific controllable paths in the phase space. We address these findings towards ultimate quest for prediction and selective control of quantum particle trajectories. In addition, presented protocols could represent valuable tool for reducing background noise and uncertainty in low-dimensional and operationally meaningful, scalable complex systems.

      16. '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.

      17. [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.

      18. 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

      19. Two-particle quantum walks applied to the graph isomorphism problem

        NASA Astrophysics Data System (ADS)

        Gamble, John King; Friesen, Mark; Zhou, Dong; Joynt, Robert; Coppersmith, S. N.

        2011-03-01

        We show that an algorithm based on the dynamics of interacting quantum particles is more powerful than the corresponding algorithm for non-interacting particles. Specifically, our algorithm attempts to determine whether two graphs are isomorphic. We focus on strongly regular graphs (SRGs), a class of graphs with particularly high symmetry. By studying the dynamical evolution of two-particle quantum walks on pairs of non-isomorphic SRG's, we show that interacting particles can distinguish non-isomorphic graphs that noninteracting particles cannot. First, we prove that quantum walks of two noninteracting particles cannot distinguish pairs of non-isomorphic SRG's. Next, we demonstrate numerically that two interacting bosons are more powerful, in that their quantum walks distinguish all non-isomorphic pairs of SRGs we tried, including those with up to 64 vertices. Finally, we find a set of operators that determine these evolutions. This work was supported in part by ARO and DOD (W911NF-09-1-0439). J.K.G. acknowledges support from the NSF.

      20. Particle Physics Catalysis of Thermal Big Bang Nucleosynthesis

        SciTech Connect

        Pospelov, Maxim

        2007-06-08

        We point out that the existence of metastable, {tau}>10{sup 3} s, negatively charged electroweak-scale particles (X{sup -}) 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{sup -} with helium, formed at temperatures of about T=10{sup 8} K, lead to the catalytic enhancement of {sup 6}Li production, which is 8 orders of magnitude more efficient than the standard channel. In particle physics models where subsequent decay of X{sup -} 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{sup -} particles ({tau}>10{sup 5} s) relative to entropy of n{sub X{sup -}}/s < or approx. 3x10{sup -17}, which is one of the most stringent probes of electroweak scale remnants known to date.

      1. Early developments: Particle physics aspects of cosmic rays

        NASA Astrophysics Data System (ADS)

        Grupen, Claus

        2014-01-01

        Cosmic rays is the birthplace of elementary particle physics. The 1936 Nobel prize was shared between Victor Hess and Carl Anderson. Anderson discovered the positron in a cloud chamber. The positron was predicted by Dirac several years earlier. In subsequent cloud chamber investigations Anderson and Neddermeyer saw the muon, which for some time was considered to be a candidate for the Yukawa particle responsible for nuclear binding. Measurements with nuclear emulsions by Lattes, Powell, Occhialini and Muirhead clarified the situation by the discovery of the charged pions in cosmic rays. The cloud chamber continued to be a powerful instrument in cosmic ray studies. Rochester and Butler found V's, which turned out to be shortlived neutral kaons decaying into a pair of charged pions. Also Λ's, Σ's, and Ξ's were found in cosmic rays. But after that accelerators and storage rings took over. The unexpected renaissance of cosmic rays started with the search for solar neutrinos and the observation of the supernova 1987A. Cosmic ray neutrino results were best explained by the assumption of neutrino oscillations opening a view beyond the standard model of elementary particles. After 100 years of cosmic ray research we are again at the beginning of a new era, and cosmic rays may contribute to solve the many open questions, like dark matter and dark energy, by providing energies well beyond those of accelerators.

      2. Three-particle hyper-entanglement: teleportation and quantum key distribution

        NASA Astrophysics Data System (ADS)

        Perumangatt, Chithrabhanu; Abdul Rahim, Aadhi; Salla, Gangi Reddy; Prabhakar, Shashi; Samanta, Goutam Kumar; Paul, Goutam; Singh, Ravindra Pratap

        2015-10-01

        We present a scheme to generate three-particle hyper-entanglement utilizing polarization and orbital angular momentum (OAM) of photons. We show that the generated state can be used to teleport a two-qubit state described by the polarization and the OAM. The proposed quantum system has also been used to describe a new efficient quantum key distribution (QKD) protocol. We give a sketch of the experimental arrangement to realize the proposed teleportation and the QKD.

      3. Quantum Phase Coherence in Mesoscopic Transport Devices with Two-Particle Interaction.

        PubMed

        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

      4. Quantum Phase Coherence in Mesoscopic Transport Devices with Two-Particle Interaction

        NASA Astrophysics Data System (ADS)

        Wang, Zhimei; Guo, Xiaofang; Xue, Haibin; Xue, Naitao; Liang, J.-Q.

        2015-08-01

        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.

      5. 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

      6. Efficiency of quantum energy teleportation within spin-1/2 particle pairs

        NASA Astrophysics Data System (ADS)

        Frey, Michael R.

        2016-03-01

        A protocol for quantum energy teleportation (QET) is known for a so-called minimal spin-1/2 particle pair model. We extend this protocol to explicitly admit quantum weak measurements at its first stage. The extended protocol is applied beyond the minimal model to spin-1/2 particle pairs whose Hamiltonians are of a general class characterized by orthogonal pairs of entangled eigenstates. The energy transfer efficiency of the extended QET protocol is derived for this setting, and we show that weaker measurement yields greater efficiency. In the minimal particle pair model, for example, the efficiency can be doubled by this means. We also show that the QET protocol's transfer efficiency never exceeds 100 %, supporting the understanding that quantum energy teleportation is, indeed, an energy transfer protocol, rather than a protocol for remotely catalyzing local extraction of system energy already present.

      7. 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.

      8. Creation of particles in a cyclic universe driven by loop quantum cosmology

        NASA Astrophysics Data System (ADS)

        Tavakoli, Yaser; Fabris, Júlio C.

        2015-05-01

        We consider an isotropic and homogeneous universe in loop quantum cosmology (LQC). We assume that the matter content of the universe is dominated by dust matter in early time and a phantom matter at late time which constitutes the dark energy component. The quantum gravity modifications to the Friedmann equation in this model indicate that the classical big bang singularity and the future big rip singularity are resolved and are replaced by quantum bounce. It turns out that the big bounce and recollapse in the herein model contribute to a cyclic scenario for the universe. We then study the quantum theory of a massive, nonminimally coupled scalar field undergoing cosmological evolution from primordial bounce towards the late time bounce. In particular, we solve the Klein-Gordon equation for the scalar field in the primordial and late time regions, in order to investigate particle production phenomena at late time. By computing the energy density of created particles at late time, we show that this density is negligible in comparison to the quantum background density at Planck era. This indicates that the effects of quantum particle production do not influence the future bounce.

      9. Topological phases and polaron physics in ultracold quantum gases

        NASA Astrophysics Data System (ADS)

        Grusdt, Fabian

        2016-05-01

        The description of quantum many-body systems poses a formidable theoretical challenge. A seemingly simple problem is the coupling of a single impurity atom to non-interacting Bogoliubov phonons in a surrounding Bose-Einstein condensate. The system can be described by a polaron model at intermediate couplings - an 80 year problem. The situation has been realized experimentally, but when the impurity mass is small compared to the Boson mass, neither mean-field nor strong-coupling expansions are valid anymore. Now the impurity acts as an exchange particle, mediating phonon-phonon interactions. In this talk I present a semi-analytical solution to the polaron problem. I will show that the approach can be generalized to solve far-from equilibrium polaron problems, too, and elaborate on connections with recent experiments involving ultracold atoms and photons. A completely different class of many-body problems are systems with topological order. In recent years we have seen an uprise of cold-atomic or photonic implementations of artificial gauge fields, providing a corner stone for the realization of topological phases of matter. In the second part of my talk, I will address the challenging problem how non-local topological orders can be detected. It will be demonstrated that many-body topological invariants can be measured, making use of mobile impurities as coherent probes of the highly entangled groundstates. I will discuss Laughlin states and comment on possible realizations using ultracold atoms.

      10. Origin of macroscopic single-particle quantum behavior in Bose-Einstein-condensed systems

        NASA Astrophysics Data System (ADS)

        Mayers, J.

        2008-09-01

        It is shown that any Bose-Einstein-condensed fluid in its ground state will exhibit macroscopic single-particle quantum behavior (MSPQB). That is, (1) the many-particle wave function Ψ(r1,…,rn) factors into a single-particle product ∏nη(rn) ; (2) the function η(r) extends over macroscopic length scales and obeys the usual quantum equations for particle flux in a single-particle system; and (3) η(r) obeys a nonlinear single-particle Schrödinger equation. The latter equation reduces to the Gross-Pitaevskii equation when interactions are weak and determines the density distribution of the fluid and the time development of this distribution. The arguments used rely only on elementary concepts of probability theory and many-particle wave mechanics and are valid even in strongly interacting fluids such as superfluid He4 . It is shown that Bose-Einstein condensation implies that the N -particle wave function Ψ is delocalized. That is, if one considers a single-particle coordinate r , then for all values that occur of the other N-1 coordinates, Ψ is a nonzero function of r over a region of space proportional to V , where V is the total volume within which the fluid is contained. MSPQB is a consequence of this delocalization and the absence of long-range correlations between particle positions in fluids. The results are accurate provided that only averages over regions of space containing many particles are considered. For averages over volumes of space containing NΩ particles, inaccuracies due to quantum fluctuations are ˜1/NΩ .

      11. 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. PMID:27391707

      12. Classical Physics and the Bounds of Quantum Correlations

        NASA Astrophysics Data System (ADS)

        Frustaglia, Diego; Baltanás, José P.; Velázquez-Ahumada, María C.; Fernández-Prieto, Armando; Lujambio, Aintzane; Losada, Vicente; Freire, Manuel J.; Cabello, Adán

        2016-06-01

        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.

      13. 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…

      14. PREFACE: IARD 2010: The 7th Biennial Conference on Classical and Quantum Relativistic Dynamics of Particles and Fields

        NASA Astrophysics Data System (ADS)

        Horwitz, Lawrence; Hu, Bei-Lok; Lee, Da-Shin; Gill, Tepper; Land, Martin

        2011-12-01

        properties of spacetime structure. The scope of this series of conferences is, however, much wider. There have been recent develpments in the understanding of the quantum properties of spacetime, the application of quantum field theory and statistical quantum field theory to problems in relativistic dynamics, as well as new techniques in general relativity; some of these topics have been discussed in the IARD 2010 conference, and which will be reported in these Proceedings. It was for this purpose, to bring together researchers from a wide variety of fields, such as particle physics, astrophysics, cosmology, heavy ion collisions, plasma research, and mathematical physics, with a common interest in relativistic dynamics, that this Association was founded. The International Association for Relativistic Dynamics was organized at its first meeting as an informal session of seminars among researchers with common interest in February 1998 in Houston, Texas, with John R Fanchi as president. The second meeting took place, in 2000, at Bar Ilan University in Ramat Gan, Israel, the third, in 2002, at Howard University in Washington, DC, and the fourth, on 12-19 June 2004, in Saas Fee, Switzerland. In 2006, the meeting took place at the University of Connecticut campus in Storrs, Connecticut, and the sixth meeting, in Thessaloniki, Greece. The seventh meeting, took place at the National Dong Hwa University in Hulien, Taiwan from 30 May to 1 June 2010. This meeting forms the basis for the Proceedings that are recorded in this volume of 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, statistical quantum field theory and its potential applications to relativistic quantum information theory, cosmological problems, and in the dynamics of systems described in the framework of general

      15. 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…

      16. Which is the quantum decay law of relativistic particles?

        NASA Astrophysics Data System (ADS)

        Alavi, S. A.; Giunti, C.

        2015-03-01

        We discuss the relation between the quantum-mechanical survival probability of an unstable system in motion and that of the system at rest. The usual definition of the survival probability which takes into account only the time evolution of an unstable system leads to a relation between the survival probability of the system in motion and that of the system at rest which is different from the standard relation based on relativistic time dilation. This approach led other authors to claim non-standard quantum-mechanical effects which are in clear contradiction with Special Relativity. We show that an appropriate relativistic definition of the survival probability which takes into account also the space evolution of an unstable system leads to the standard relation between the survival probability of the system in motion and that of the system at rest, in agreement with Special Relativity. We present a rigorous derivation of this result based on a wave packet treatment.

      17. Stochastic duality of ASEP with two particle types via symmetry of quantum groups of rank two

        NASA Astrophysics Data System (ADS)

        Kuan, Jeffrey

        2016-03-01

        We study two generalizations of the asymmetric simple exclusion process (ASEP) with two types of particles, which will be called type A 2 ASEP and type C 2 ASEP. Particles of type 1 force particles of type 2 to switch places. In the C 2 case, particles of type 2 can only influence the jump rates of particles of type 1, and in the A 2 case particles of type 2 do not influence particles of type 1 at all. We prove that the processes are self-dual and explicitly write the duality function, which is a generalization of the self-duality function for ASEP. The construction and proofs of duality are accomplished using symmetry of the quantum groups {{ U }}q({{gl}}3) and {{ U }}q({{sp}}4) for the A 2 and C 2 ASEP respectively.

      18. ``Simplest Molecule'' Clarifies Modern Physics II. Relativistic Quantum Mechanics

        NASA Astrophysics Data System (ADS)

        Harter, William; Reimer, Tyle

        2015-05-01

        A ``simplest molecule'' consisting of CW- laser beam pairs helps to clarify relativity from poster board - I. In spite of a seemingly massless evanescence, an optical pair also clarifies classical and quantum mechanics of relativistic matter and antimatter. Logical extension of (x,ct) and (ω,ck) geometry gives relativistic action functions of Hamiltonian, Lagrangian, and Poincare that may be constructed in a few ruler-and-compass steps to relate relativistic parameters for group or phase velocity, momentum, energy, rapidity, stellar aberration, Doppler shifts, and DeBroglie wavelength. This exposes hyperbolic and circular trigonometry as two sides of one coin connected by Legendre contact transforms. One is Hamiltonian-like with a longitudinal rapidity parameter ρ (log of Doppler shift). The other is Lagrange-like with a transverse angle parameter σ (stellar aberration). Optical geometry gives recoil in absorption, emission, and resonant Raman-Compton acceleration and distinguishes Einstein rest mass, Galilean momentum mass, and Newtonian effective mass. (Molecular photons appear less bullet-like and more rocket-like.) In conclusion, modern space-time physics appears as a simple result of the more self-evident Evenson's axiom: ``All colors go c.''

      19. "simplest Molecule" Clarifies Modern Physics II. Relativistic Quantum Mechanics

        NASA Astrophysics Data System (ADS)

        Reimer, T. C.; Harter, W. G.

        2014-06-01

        A "simplest molecule" consisting of CW-laser beam pairs helps to clarify relativity in Talk I. In spite of a seemingly massless evanescence, an optical pair also clarifies classical and quantum mechanics of relativistic matter and anti-matter. *Logical extension of (x,ct) and (ω,ck) geometry gives relativistic action functions of Hamiltonian, Lagrangian, and Poincare that may be constructed in a few ruler-and-compass steps to relate relativistic parameters for group or phase velocity, momentum, energy, rapidity, stellar aberration, Doppler shifts, and DeBroglie wavelength. This exposes hyperbolic and circular trigonometry as two sides of one coin connected by Legendre contact transforms. One is Hamiltonian-like with a longitudinal rapidity parameter ρ (log of Doppler shift). The other is Lagrange-like with a transverse angle parameter σ (stellar aberration). Optical geometry gives recoil in absorption, emission, and resonant Raman-Compton acceleration and distinguishes Einstein rest mass, Galilean momentum mass, and Newtonian effective mass. (Molecular photons appear less bullet-like and more rocket-like.) In conclusion, modern space-time physics appears as a simple result of the more self-evident Evenson's axiom: "All colors go c."

      20. 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:

      21. The Third Generation as a Probe for New Physics: Experimental and Technological Approach (4 - 11 September)
      22. The Quest for Unification Theory Confronts Experiment (11 - 18 September)
      23. Constituents Fundamental Forces and Symmetries of the Universe (20 - 26 September)
      24. 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