Presenting particle physics and quantum mechanics to the general public
Strauss, J
2015-01-01
The job of a physicist is to describe Nature. General features, hypotheses and theories help to describe physics phenomena at a more abstract, fundamental level, and are sometimes tacitly assigned some sort of real existence; doing so appears to be of little harm in most of classical physics. However, missing any tangible connection to everyday experience, one better always bears in mind the descriptive nature of any efforts to grasp the quantum. And elementary particles interact in the quantum world, of course. When communicating the world of elementary particles to the general public, the Bayesian approach of an ever ongoing updating of the depiction of reality turns out to be virtually indispensable. The human experience of providing a series of increasingly better descriptions generates plenty of personal pleasures, for researchers as well as for amateurs. A suggestive analogy for improving our understanding of the world, even the seemingly paradoxical quantum world, may be found in recent insight into ho...
Counterfactual quantum-information transfer without transmitting any physical particles.
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
PHYSICAL REVIEW A 89, 024102 (2014) Tracing the past of a quantum particle
Vaidman, Lev
2014-01-01
PHYSICAL REVIEW A 89, 024102 (2014) Tracing the past of a quantum particle L. Vaidman Raymond and Beverly Sackler School of Physics and Astronomy, Tel-Aviv University, Tel-Aviv 69978, Israel (Received 29 December 2013; published 13 February 2014) The question "Where was a quantum particle between pre
PHYSICAL REVIEW A 87, 052104 (2013) Past of a quantum particle
Vaidman, Lev
2013-01-01
trajectory with a nonvanishing quantum wave of the particle between its emission and detection points, it seems "safe" to associate the past of the particle with this trajectory. A method for analyzing the pastPHYSICAL REVIEW A 87, 052104 (2013) Past of a quantum particle L. Vaidman Raymond and Beverly
Physics 139B Fall 2009 Quantum Mechanics of a Charged Particle in an Electromagnetic Field
California at Santa Cruz, University of
of the fact that the charged particle moves on a trajectory r = r(t). Noting that vi dxi/dt [where r (x1 , xPhysics 139B Fall 2009 Quantum Mechanics of a Charged Particle in an Electromagnetic Field These notes present the motivation for the Schrodinger equation for a charged particle in an external
Physics 139B Fall 2009 Quantum Mechanics of a Charged Particle in an Electromagnetic Field
California at Santa Cruz, University of
) implicit timeÂdependence by virtue of the fact that the charged particle moves on a trajectory #r = #rPhysics 139B Fall 2009 Quantum Mechanics of a Charged Particle in an Electromagnetic Field These notes present the motivation for the Schrodinger equation for a charged particle in an external
Physics 216 Spring 2012 Quantum Mechanics of a Charged Particle in an Electromagnetic Field
California at Santa Cruz, University of
Âdependence by virtue of the fact that the charged particle moves on a trajectory #r = #r(t). Noting that v i # dx i /dtPhysics 216 Spring 2012 Quantum Mechanics of a Charged Particle in an Electromagnetic Field These notes present the Schrodinger equation for a charged particle in an external electromagnetic field
Physics 216 Spring 2012 Quantum Mechanics of a Charged Particle in an Electromagnetic Field
California at Santa Cruz, University of
time-dependence by virtue of the fact that the charged particle moves on a trajectory r = r(t). NotingPhysics 216 Spring 2012 Quantum Mechanics of a Charged Particle in an Electromagnetic Field These notes present the Schrodinger equation for a charged particle in an external electromagnetic field
Y. Aoki; Z. Fodor; S. D. Katz; K. K. Szabo
Quantum chromodynamics (QCD) is the theory of the strong interaction, explaining (for example) the binding of three almost massless quarks into a much heavier proton or neutron - and thus most of the mass of the visible Universe. The standard model of particle physics predicts a QCD-related transition that is relevant for the evolution of the early Universe. At low
Quantum Physics: An Introduction
NSDL National Science Digital Library
Introduction to Quantum Physics concepts with an activity demonstrating Heisenberg's Uncertainty Principle, wave/particle duality, Planck's Constant, de Broglie wavelength, and how Newton's Laws go right out the window on a quantum level.
F. R. Klinkhamer; G. E. Volovik
2004-11-04
We discuss the quantum phase transition that separates a vacuum state with fully-gapped fermion spectrum from a vacuum state with topologically-protected Fermi points (gap nodes). In the context of condensed-matter physics, such a quantum phase transition with Fermi point splitting may occur for a system of ultracold fermionic atoms in the region of the BEC-BCS crossover, provided Cooper pairing occurs in the non-s-wave channel. For elementary particle physics, the splitting of Fermi points may lead to CPT violation, neutrino oscillations, and other phenomena.
Quantum particles from classical statistics
C. Wetterich
2010-02-11
Quantum particles and classical particles are described in a common setting of classical statistical physics. The property of a particle being "classical" or "quantum" ceases to be a basic conceptual difference. The dynamics differs, however, between quantum and classical particles. We describe position, motion and correlations of a quantum particle in terms of observables in a classical statistical ensemble. On the other side, we also construct explicitly the quantum formalism with wave function and Hamiltonian for classical particles. For a suitable time evolution of the classical probabilities and a suitable choice of observables all features of a quantum particle in a potential can be derived from classical statistics, including interference and tunneling. Besides conceptual advances, the treatment of classical and quantum particles in a common formalism could lead to interesting cross-fertilization between classical statistics and quantum physics.
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.
Research in theoretical particle physics
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)
6.728 Applied Quantum and Statistical Physics, Fall 2002
Bulovic, Vladimir, 1970-
Elementary quantum mechanics and statistical physics. Introduces applied quantum physics. Emphasizes experimental basis for quantum mechanics. Applies Schrodinger's equation to the free particle, tunneling, the harmonic ...
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)
Aoki, Y; Endrodi, G; Fodor, Z; Katz, S D; Szabó, K K
2006-10-12
Quantum chromodynamics (QCD) is the theory of the strong interaction, explaining (for example) the binding of three almost massless quarks into a much heavier proton or neutron--and thus most of the mass of the visible Universe. The standard model of particle physics predicts a QCD-related transition that is relevant for the evolution of the early Universe. At low temperatures, the dominant degrees of freedom are colourless bound states of hadrons (such as protons and pions). However, QCD is asymptotically free, meaning that at high energies or temperatures the interaction gets weaker and weaker, causing hadrons to break up. This behaviour underlies the predicted cosmological transition between the low-temperature hadronic phase and a high-temperature quark-gluon plasma phase (for simplicity, we use the word 'phase' to characterize regions with different dominant degrees of freedom). Despite enormous theoretical effort, the nature of this finite-temperature QCD transition (that is, first-order, second-order or analytic crossover) remains ambiguous. Here we determine the nature of the QCD transition using computationally demanding lattice calculations for physical quark masses. Susceptibilities are extrapolated to vanishing lattice spacing for three physical volumes, the smallest and largest of which differ by a factor of five. This ensures that a true transition should result in a dramatic increase of the susceptibilities. No such behaviour is observed: our finite-size scaling analysis shows that the finite-temperature QCD transition in the hot early Universe was not a real phase transition, but an analytic crossover (involving a rapid change, as opposed to a jump, as the temperature varied). As such, it will be difficult to find experimental evidence of this transition from astronomical observations. PMID:17035999
Nuclear and Particle Physics applications of the Bohm Picture of Quantum Mechanics
A. Miranda
2009-01-09
Approximation methods for calculating individual particle/ field motions in spacetime at the quantum level of accuracy (a key feature of the Bohm Picture of Quantum Mechanics (BP)), are studied. Modern textbook presentations of Quantum Theory are used throughout, but only to provide the necessary, already existing, tested formalisms and calculational techniques. New coherent insights, reinterpretations of old solutions and results, and new (in principle testable) quantitative and qualitative predictions, can be obtained on the basis of the BP that complete the standard type of postdictions and predictions.
NSDL National Science Digital Library
Particle Data Group of Lawrence Berkeley National Laboratory
The particle physics group of Lawrence Berkeley National Laboratory presents and award winning interactive tour of quarks, neutrinos, antimatter, extra dimensions, dark matter, accelerators, and particle detectors.
"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 excellent working conditions. We would like to thank Martina Mende for all her work in helping to organize this conference. Details of the conference can be found under: https://indico.desy.de/conferenceDisplay.py?confId=8107
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)
Rosenfeld, Carl [Univ of South Carolina; Mishra, Sanjib R. [Univ of South Carolina; Petti, Roberto [Univ of South Carolina; Purohit, Milind V. [Univ of South Carolina
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, which collected data at SLAC until 2008. They continued to analyze the voluminous BaBar data with an emphasis on precision tests of Quantum Chromodynamics and on properties of the "eta_B," a bottom quark paired in a meson with a strange quark. The ATLAS experiment became the principal research focus for Purohit. One of the world's largest pieces of scientific equipment, ATLAS observes particle collisions at the highest-energy particle accelerator ever built, the Large Hadron Collider (LHC) at CERN. Our efforts on ATLAS included participation in the commissioning, calibration, and installation of components called "CSCs". The unprecedented energy of 14 TeV enabled the ATLAS and CMS collaborations to declare discovery of the famous Higgs particle in 2012.
Kearns, Edward [Boston Universiy] [Boston Universiy
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.
NSDL National Science Digital Library
This Fermilab website offers physicists the chance to educate individuals about the "fundamental particles and forces of our universe." The website offers a database containing over 250 hands-on activities, special events, research participation, and other educational and outreach programs. The information can be searched by state, audience, and institution. The database offers a brief description of each program and a link to its website. Students can learn about the basics of particle physics through a concise article. Educators can discover why particle physics education is important.
m anchester particle physics MAN/HEP/97Â1 3rd January, 1997 FourÂfermion events in electron of Physics Manchester University Manchester M13 9PL England Abstract A study of neutralÂcurrent fourÂfermion at DPF '96, Minneapolis #12; 1 Introduction FourÂfermion processes are important as a background to Higgs
Information and Particle Physics
Wei Khim Ng; Rajesh R. Parwani
2011-03-26
Information measures for relativistic quantum spinors are constructed to satisfy various postulated properties such as normalisation invariance and positivity. Those measures are then used to motivate generalised Lagrangians meant to probe shorter distance physics within the maximum uncertainty framework. The modified evolution equations that follow are necessarily nonlinear and simultaneously violate Lorentz invariance, supporting previous heuristic arguments linking quantum nonlinearity with Lorentz violation. The nonlinear equations also break discrete symmetries. We discuss the implications of our results for physics in the neutrino sector and cosmology.
Particle physics and cosmology
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.
Quantum Physics Einstein's Gravity
Visser, Matt
Quantum Physics confronts Einstein's Gravity Matt Visser Physics Department Washington University Saint Louis USA Science Saturdays 13 October 2001 #12; Quantum Physics confronts Einstein's Gravity and with Einstein's theory of gravity (the general relativity) is still the single biggest theoretical problem
NSDL National Science Digital Library
Supported by the Particle Physics and Astronomy Research Council, this website was created to educate everyone about particle physics. Individuals can find archived press releases, news articles, and particle physics pictures. The website summarizes the role of particle physics in industry and offers links to educational and employment opportunities. Students and educators can find out about famous physicists and the principles of particle physics and its history. Scientists can locate high energy physics universities, groups, and experiments.
Quantum Physics and Nanotechnology
Vladimir K. Nevolin
2011-06-06
Experimental studies of infinite (unrestricted at least in one direction) quantum particle motion using probe nanotechnologies have revealed the necessity of revising previous concepts of their motion. Particularly, quantum particles transfer quantum motion nonlocality energy beside classical kinetic energy, in other words, they are in two different kinds of motion simultaneously. The quantum component of the motion energy may be quite considerable under certain circumstances. Some new effects were predicted and proved experimentally in terms of this phenomenon. A new prototype refrigerating device was tested, its principle of operation being based on the effect of transferring the quantum component of the motion energy.
Non-accelerator Particle Physics
Wechsler, Risa H.
Non-accelerator Particle Physics and Neutrino Physics Research programs of: Prof. Martin that often connect particle physics with astrophysics and cosmology Some questions: - What particles of the neutrino? #12;The techniques: Laboratory experiments, in the style of particle physics · High energy
Quantum Physics in a different ontology
Nalin de Silva
2010-06-24
It is shown that neither the wave picture nor the ordinary particle picture offers a satisfactory explanation of the double-slit experiment. The Physicists who have been successful in formulating theories in the Newtonian Paradigm with its corresponding ontology find it difficult to interpret Quantum Physics which deals with particles that are not sensory perceptible. A different interpretation of Quantum Physics based in a different ontology is presented in what follows. According to the new interpretation Quantum particles have different properties from those of Classical Newtonian particles. The interference patterns are explained in terms of particles each of which passes through both slits.
Research program in particle physics
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.
an error then the maximum number of useful samples is of order (N=n) 2 . #12; 1. Introduction The bootstrapm anchester particle physics MAN/HEP/99/4 April 14, 2000 Application of the Bootstrap resampling Manchester M13 9PL England Abstract When using the Monte Carlo Bootstrap technique to estimate the mean
NASA Astrophysics Data System (ADS)
Yao, W.-M.; Amsler, C.; Asner, D.; Barnett, R. M.; Beringer, J.; Burchat, P. R.; Carone, C. D.; Caso, C.; Dahl, O.; D'Ambrosio, G.; De Gouvea, A.; Doser, M.; Eidelman, S.; Feng, J. L.; Gherghetta, T.; Goodman, M.; Grab, C.; Groom, D. E.; Gurtu, A.; Hagiwara, K.; Hayes, K. G.; Hernández-Rey, J. J.; Hikasa, K.; Jawahery, H.; Kolda, C.; Kwon, Y.; Mangano, M. L.; Manohar, A. V.; Masoni, A.; Miquel, R.; Mönig, K.; Murayama, H.; Nakamura, K.; Navas, S.; Olive, K. A.; Pape, L.; Patrignani, C.; Piepke, A.; Punzi, G.; Raffelt, G.; Smith, J. G.; Tanabashi, M.; Terning, J.; Törnqvist, N. A.; sTrippe, T. G.; Vogel, P.; Watari, T.; Wohl, C. G.; Workman, R. L.; Zyla, P. A.; Armstrong, B.; Harper, G.; Lugovsky, V. S.; Schaffner, P.; Artuso, M.; Babu, K. S.; Band, H. R.; Barberio, E.; Battaglia, M.; Bichsel, H.; Biebel, O.; Bloch, P.; Blucher, E.; Cahn, R. N.; Casper, D.; Cattai, A.; Ceccucci, A.; Chakraborty, D.; Chivukula, R. S.; Cowan, G.; Damour, T.; DeGrand, T.; Desler, K.; Dobbs, M. A.; Drees, M.; Edwards, A.; Edwards, D. A.; Elvira, V. D.; Erler, J.; Ezhela, V. V.; Fetscher, W.; Fields, B. D.; Foster, B.; Froidevaux, D.; Gaisser, T. K.; Garren, L.; Gerber, H.-J.; Gerbier, G.; Gibbons, L.; Gilman, F. J.; Giudice, G. F.; Gritsan, A. V.; Grünewald, M.; Haber, H. E.; Hagmann, C.; Hinchliffe, I.; Höcker, A.; Igo-Kemenes, P.; JAckson, J. D.; Johnson, K. F.; Karlen, D.; Kayser, B.; Kirkby, D.; Klein, S. R.; Kleinknecht, K.; Knowles, I. G.; Kowalewski, R. V.; Kreitz, P.; Kursche, B.; Kuyanov, Yu. V.; Lahav, O.; Langacker, P.; Liddle, A.; Ligeti, Z.; Liss, T. M.; Littenberg, L.; Liu, J. C.; Lugovsky, K. S.; Lugovsky, s. B.; Mannel, T.; Manley, D. M.; Marciano, W. J.; Martin, A. D.; Milstead, D.; Narain, M.; Nason, P.; Nir, Y.; Peacock, J. A.; Prell, S. A.; Quadt, A.; Raby, S.; Ratcliff, B. N.; Razuvaev, E. A.; Renk, B.; Richardson, P.; Roesler, S.; Rolandi, G.; Ronan, M. T.; Rosenberg, L. J.; Sachrajda, C. T.; Sakai, Y.; Sarkar, S.; Schmitt, M.; Schneider, O.; Scott, D.; Sjöstrand, T.; Smoot, G. F.; Sokolsky, P.; Spanier, S.; Spieler, H.; Stahl, A.; Stanev, T.; Streitmatter, R. E.; Sumiyoshi, T.; Tkachenko, N. P.; Trilling, G. H.; Valencia, G.; van Bibber, K.; Vincter, M. G.; Ward, D. R.; Webber, B. R.; Wells, J. D.; Whalley, M.; Wolfenstsein, L.; Womersley, J.; Woody, C. L.; Yamamoto, A.; Zenin, O. V.; Zhang, J.; Zhu, R.-Y.
2006-07-01
This biennial Review summarizes much of particle physics. Using data from previous editions, plus 2633 new measurements from 689 papers, we list, evaluate, and average measured properties of gauge bosons, leptons, quarks, mesons, and baryons. We also summarize searches for hypothetical particles such as Higgs bosons, heavy neutrinos, and supersymmetric particles. 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 the Standard Model, particle detectors, probability, and statistics. Among the 110 reviews are many that are new or heavily revised including those on CKM quark-mixing matrix, Vud & Vus, Vcb & Vub, top quark, muon anomalous magnetic moment, extra dimensions, particle detectors, cosmic background radiation, dark matter, cosmological parameters, and big bang cosmology. A booklet is available containing the Summary Tables and abbreviated versions of some of the other sections of this full Review. All tables, listings, and reviews (and errata) are also available on the Particle Data Group website: http://pdg.lbl.gov.
NASA Astrophysics Data System (ADS)
Amsler, C.; Doser, M.; Antonelli, M.; Asner, D. M.; Babu, K. S.; Baer, H.; Band, H. R.; Barnett, R. M.; Bergren, E.; Beringer, J.; Bernardi, G.; Bertl, W.; Bichsel, H.; Biebel, O.; Bloch, P.; Blucher, E.; Blusk, S.; Cahn, R. N.; Carena, M.; Caso, C.; Ceccucci, A.; Chakraborty, D.; Chen, M.-C.; Chivukula, R. S.; Cowan, G.; Dahl, O.; D'Ambrosio, G.; Damour, T.; de Gouvêa, A.; DeGrand, T.; Dobrescu, B.; Drees, M.; Edwards, D. A.; Eidelman, S.; Elvira, V. D.; Erler, J.; Ezhela, V. V.; Feng, J. L.; Fetscher, W.; Fields, B. D.; Foster, B.; Gaisser, T. K.; Garren, L.; Gerber, H.-J.; Gerbier, G.; Gherghetta, T.; Giudice, G. F.; Goodman, M.; Grab, C.; Gritsan, A. V.; Grivaz, J.-F.; Groom, D. E.; Grünewald, M.; Gurtu, A.; Gutsche, T.; Haber, H. E.; Hagiwara, K.; Hagmann, C.; Hayes, K. G.; Hernández-Rey, J. J.; Hikasa, K.; Hinchliffe, I.; Höcker, A.; Huston, J.; Igo-Kemenes, P.; Jackson, J. D.; Johnson, K. F.; Junk, T.; Karlen, D.; Kayser, B.; Kirkby, D.; Klein, S. R.; Knowles, I. G.; Kolda, C.; Kowalewski, R. V.; Kreitz, P.; Krusche, B.; Kuyanov, Yu. V.; Kwon, Y.; Lahav, O.; Langacker, P.; Liddle, A.; Ligeti, Z.; Lin, C.-J.; Liss, T. M.; Littenberg, L.; Liu, J. C.; Lugovsky, K. S.; Lugovsky, S. B.; Mahlke, H.; Mangano, M. L.; Mannel, T.; Manohar, A. V.; Marciano, W. J.; Martin, A. D.; Masoni, A.; Milstead, D.; Miquel, R.; Mönig, K.; Murayama, H.; Nakamura, K.; Narain, M.; Nason, P.; Navas, S.; Nevski, P.; Nir, Y.; Olive, K. A.; Pape, L.; Patrignani, C.; Peacock, J. A.; Piepke, A.; Punzi, G.; Quadt, A.; Raby, S.; Raffelt, G.; Ratcliff, B. N.; Renk, B.; Richardson, P.; Roesler, S.; Rolli, S.; Romaniouk, A.; Rosenberg, L. J.; Rosner, J. L.; Sachrajda, C. T.; Sakai, Y.; Sarkar, S.; Sauli, F.; Schneider, O.; Scott, D.; Seligman, W. G.; Shaevitz, M. H.; Sjöstrand, T.; Smith, J. G.; Smoot, G. F.; Spanier, S.; Spieler, H.; Stahl, A.; Stanev, T.; Stone, S. L.; Sumiyoshi, T.; Tanabashi, M.; Terning, J.; Titov, M.; Tkachenko, N. P.; Törnqvist, N. A.; Tovey, D.; Trilling, G. H.; Trippe, T. G.; Valencia, G.; van Bibber, K.; Vincter, M. G.; Vogel, P.; Ward, D. R.; Watari, T.; Webber, B. R.; Weiglein, G.; Wells, J. D.; Whalley, M.; Wheeler, A.; Wohl, C. G.; Wolfenstein, L.; Womersley, J.; Woody, C. L.; Workman, R. L.; Yamamoto, A.; Yao, W.-M.; Zenin, O. V.; Zhang, J.; Zhu, R.-Y.; Zyla, P. A.; Harper, G.; Lugovsky, V. S.; Schaffner, P.; Particle Data Group
2008-09-01
This biennial Review summarizes much of particle physics. Using data from previous editions, plus 2778 new measurements from 645 papers, we list, evaluate, and average measured properties of gauge bosons, leptons, quarks, mesons, and baryons. We also summarize searches for hypothetical particles such as Higgs bosons, heavy neutrinos, and supersymmetric particles. 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 the Standard Model, particle detectors, probability, and statistics. Among the 108 reviews are many that are new or heavily revised including those on CKM quark-mixing matrix, V ud & V us, V cb & V ub, top quark, muon anomalous magnetic moment, extra dimensions, particle detectors, cosmic background radiation, dark matter, cosmological parameters, and big bang cosmology. A booklet is available containing the Summary Tables and abbreviated versions of some of the other sections of this full Review. All tables, listings, and reviews (and errata) are also available on the Particle Data Group website: http://pdg.lbl.gov.
Quantum interference and particle trajectories
J. Luscombe
1997-06-06
The existence of precise particle trajectories in any quantum state is accounted for in a consistent way by allowing delocalization of the particle charge. The relativistic mass of the particle remains within a small volume surrounding a singularity moving along the particle trajectory. The singularity is the source of an electric displacement field. The field induces a polarization charge in the vacuum and this charge is equated with the charge of the particle. Under dynamic conditions a distributed charge density rho(x,t) is induced in the vacuum. The volume integral of the charge density is equal to the charge of the particle and is rigorously conserved. The charge density is derived from a complex-valued physical field psi(x,t) such that rho(x,t) = |psi(x,t)|^2. The position probability density is equated with the mean charge density. The mean field psi(x,t) for many sample realizations with a given energy E and potential V(x) is the sum of the individual fields. In order for the sum to be non-zero, the components in the spectral decompositions of the individual fields must be spatially coherent. The particle has a spin frequency given by Planck's relation hv = T - V + mc^2, where T is the kinetic energy, determined from the momentum p and V is a quantum potential such that E = T + V is conserved. The instantaneous phase of the spin is given by the phase of exp(ikx) in the spectral decomposition a(k) of psi(x,t). It is spatially coherent, due to the dependence on x. The momentum probability distribution is given by the squared magnitude of the coefficients a(k). The Schrodinger equation is derived by requiring local conservation of mean energy.
The Review of Particle Physics
NSDL National Science Digital Library
The Particle Physics Group (PDG) is an "international collaboration that reviews particle physics and related areas of Astrophysics, and compiles/analyzes data on particle properties." The Web site features the 2002 publication, The Review of Particle Physics, which is described as "the most cited publication in particle physics during the last decade." Visitors have access to summary tables and conservation laws; reviews, tables, and plots; and particle listings, which list, average, evaluate, and reference various data used. Other features include a link to particle physics information and databases, archives of past reports, and other helpful resources.
Markus Arndt; Thomas Juffmann; Vlatko Vedral
2009-11-01
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 last 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 non-classical effects, has been heading towards 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.
Physics 129 Nuclear and Particle Physics
California at Santa Cruz, University of
Physics 129 Nuclear and Particle Physics Winter Quarter 2008 Instructor: David A. Williams (office materials will be distributed on the web site above. Nine texts on nuclear and particle physics, all Nuclear physics, radioactive decays, nuclear models. Properties and classification of the elementary
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…
Field theory and particle physics
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.
Introduction to Quantum Physics
NSDL National Science Digital Library
Stern, David P. (David Peter), 1931-
Authored and curated by David P. Stern, this series of eight linked web pages provide a non-mathematical introduction to atomic theory from a historical perspective. The foundations of quantum physics are traced from the discovery of atoms up to quantum tunneling. Other topics include atomic spectra and blackbody radiation. This is part of "From Stargazers to Starships", an extensive web site covering introductory topics in physics and astronomy. Spanish and French translations are available.
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.
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.
Macroscopic Quantum State Analyzed Particle by Particle
NASA Astrophysics Data System (ADS)
Beduini, Federica A.; Zieli?ska, Joanna A.; Lucivero, Vito G.; de Icaza Astiz, Yannick A.; Mitchell, Morgan W.
2015-03-01
Macroscopic quantum phenomena, e.g., superconductivity and squeezing, are believed to result from entanglement of macroscopic numbers of particles. We report the first direct study of this kind of entanglement: we use discrete quantum tomography to reconstruct the joint quantum state of photon pairs extracted from polarization-squeezed light. Our observations confirm several predictions from spin-squeezing theory [Beduini et al., Phys. Rev. Lett. 111, 143601 (2013)], including strong entanglement and entanglement of all photon pairs within the squeezing coherence time. This photon-by-photon analysis may give insight into other macroscopic many-body systems, e.g., photon Bose-Einstein condensates.
Quantum teleportation of multiple properties of a single quantum particle
Xi-Lin Wang; Xin-Dong Cai; Zu-En Su; Ming-Cheng Chen; Dian Wu; Li Li; Nai-Le Liu; Chao-Yang Lu; Jian-Wei Pan
2014-12-12
Quantum teleportation provides a "disembodied" way to transfer quantum states from one object to another at a distant location, assisted by priorly shared entangled states and a classical communication channel. In addition to its fundamental interest, teleportation has been recognized as an important element in long-distance quantum communication, distributed quantum networks and measurement-based quantum computation. There have been numerous demonstrations of teleportation in different physical systems such as photons, atoms, ions, electrons, and superconducting circuits. Yet, all the previous experiments were limited to teleportation of one degree of freedom (DoF) only. However, a single quantum particle can naturally possess various DoFs -- internal and external -- and with coherent coupling among them. A fundamental open challenge is to simultaneously teleport multiple DoFs, which is necessary to fully describe a quantum particle, thereby truly teleporting it intactly. Here, we demonstrate the first teleportation of the composite quantum states of a single photon encoded in both the spin and orbital angular momentum. We develop a method to project and discriminate hyper-entangled Bell states exploiting probabilistic quantum non-demolition measurement, which can be extended to more DoFs. We verify the teleportation for both spin-orbit product states and hybrid entangled state, and achieve a teleportation fidelity ranging from 0.57 to 0.68, above the classical limit. Our work moves a step toward teleportation of more complex quantum systems, and demonstrates an enhanced capability for scalable quantum technologies.
Quantum Cellular Automata Without Particles
David A. Meyer; Asif Shakeel
2015-06-04
Quantum Cellular Automata (QCA) constitute a natural discrete model for quantum field theory (QFT). 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, "are all nontrivial QCA QLGA?". Here we show by construction that the answer is "no"; thus there are QCA, even in $1+1$ dimensions, that have no particle interpretation.
Quantum Particle-Trajectories and Geometric Phase
M. Dima
2003-11-10
"Particle"-trajectories are defined as integrable $dx_\\mu dp^\\mu = 0$ paths in projective space. Quantum states evolving on such trajectories, open or closed, do not delocalise in $(x, p)$ projection, the phase associated with the trajectories being related to the geometric (Berry) phase and the Classical Mechanics action. High Energy Physics properties of states evolving on "particle"-trajectories are discussed.
Particle physics: Experimental
NASA Astrophysics Data System (ADS)
Lord, Jere J.; Boynton, P. E.; Burnett, T. H.; Wilkes, R. J.
1991-08-01
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 are responsible for the development and construction of critical components for the deep undersea neutrino detector facility. We have designed and developed the acoustic 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. The program uses 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.
Perspectives in Quantum Physics: Epistemological, Ontological and
Colorado at Boulder, University of
Perspectives in Quantum Physics: Epistemological, Ontological and Pedagogical of quantum mechanics, with implications for modern physics instruction. Charles #12;This thesis entitled Perspectives in Quantum Physics: Epistemological
The Standard Model of Particle Physics
Tom W. B. Kibble
2014-12-12
This is a historical account from my personal perspective of the development over the last few decades of the standard model of particle physics. The model is based on gauge theories, of which the first was quantum electrodynamics, describing the interactions of electrons with light. This was later incorporated into the electroweak theory, describing electromagnetic and weak nuclear interactions. The standard model also includes quantum chromodynamics, the theory of the strong nuclear interactions. The final capstone of the model was the Higgs particle discovered in 2012 at CERN. But the model is very far from being the last word; there are still many gaps in our understanding.
Claus Grupen
2000-01-01
In this review the basic interaction mechanisms of charged and neutral particles are presented. The ionization energy loss of charged particles is fundamental to most particle detectors and is therefore described in more detail. The production of electromagnetic radiation in various spectral ranges leads to the detection of charged particles in scintillation, Cherenkov and transition radiation counters. Photons are measured
An Introduction to Particle Physics
NSDL National Science Digital Library
The Particle Physics Department at Rutherford Appleton Laboratory (RAL) provides the Introduction to Particle Physics homepage. Particle physics is defined as "the study of the basic elements of matter and the forces acting among them...to determine the fundamental laws that control the make-up of matter and the physical universe." The Introduction provides more information on Accelerators, Detectors, Antimatter, Big Bang Science, and Dark Matter. Further information can be found in The Big Bang and The Top Quark sections, both of which provide images and in-depth summaries. Users can navigate via a contents page or through links at the bottom of the page.
Nakamura, Kenzo
2010-01-01
and ?(f f ) are the electron and fermion partial widths ofhanded incident electron to produce a fermion f traveling infermions, are their own antiparticles. An electrically charged particle (like the electron)
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,
and identification of charged pions, kaons, protons and leptons. They are each composed of a high precision silicon. tracking volume and refined calorimetry, complements these experiments by specialising in neutral particle
Quantum imitations of physical phenomena.
Ortiz, G. (Gerardo)
2001-01-01
Quantum imitation is an attempt to exploit quantum laws to advantage, and thus accomplish efficient simulation of physical phenomena. We discuss the fundamental concepts behind this new paradigm of information processing, such as the connection between models of computation and physical systems, along with the first imitation of a toy quantum many-body problem.
The Other Side of Particle Physics: Computation and
Budker, Dmitry
The Other Side of Particle Physics: Computation and Analysis Uttam Paudel Physics 129 University, and other Quantum Numbers · But.. it is still not good enough to extract 1 event out of 10,000,000 events though to be a new particle Blind Analysis · Performed without looking at the answer · Reduces
QUANTUM MECHANICS II Physics 342
Rosner, Jonathan L.
QUANTUM MECHANICS II Physics 342 KPTC 103 9:00 Â 10:20 a.m. 1 Tues., Thurs. Â Winter Quarter 2011 quantum mechanics at the graduate level. The text for Quantum Mechanics II will be J. J. Sakurai and Jim Napolitano, Modern Quantum Mechanics, Second Edition (Addison-Wesley, San Francisco, 2011). For supplemental
Quantum vacuum noise in physics and cosmology.
Davies, P. C. W.
2001-09-01
The concept of the vacuum in quantum field theory is a subtle one. Vacuum states have a rich and complex set of properties that produce distinctive, though usually exceedingly small, physical effects. Quantum vacuum noise is familiar in optical and electronic devices, but in this paper I wish to consider extending the discussion to systems in which gravitation, or large accelerations, are important. This leads to the prediction of vacuum friction: The quantum vacuum can act in a manner reminiscent of a viscous fluid. One result is that rapidly changing gravitational fields can create particles from the vacuum, and in turn the backreaction on the gravitational dynamics operates like a damping force. I consider such effects in early universe cosmology and the theory of quantum black holes, including the possibility that the large-scale structure of the universe might be produced by quantum vacuum noise in an early inflationary phase. I also discuss the curious phenomenon that an observer who accelerates through a quantum vacuum perceives a bath of thermal radiation closely analogous to Hawking radiation from black holes, even though an inertial observer registers no particles. The effects predicted raise very deep and unresolved issues about the nature of quantum particles, the role of the observer, and the relationship between the quantum vacuum and the concepts of information and entropy. (c) 2001 American Institute of Physics. PMID:12779491
Holographic Principle and Quantum Physics
Batiz, Z; Batiz, Zoltan; Chauhan, Bhag C.
2006-01-01
The concept of holography has lured philosophers of science for decades, and is becoming more and more popular on several fronts of science, e. g. in the physics of black holes. In this paper we try to understand things as if the visible universe were a reading of a low-dimensional hologram generated in hyperspace. We performed the whole process of creating and reading the hologram of a point in virtual space by using computer simulations. We claim that the fuzzieness in quantum mechanics, in statistical physics and thermodynamics is due to the fact that we do not see the real image of the object, but a holographic projection of it. We found that the projection of a point particle is a de Broglie-type wave. This indicates that holography could be the origin of the wave nature of a particle. We have also noted that one cannot stabilize the noise (or fuzzieness) in terms of the integration grid-points of the hologram, it means that one needs to give the grid-points a physical significance. So we further claim t...
Physics 375 Introduction to Quantum Physics
Kioussis, Nicholas
Physics Richard Liboff,, 4th Edition Objectives This course has the general aim: to introduce the students) the homework (20%). The letter grades will be based on the overall performance of the class. All testsPhysics 375 Introduction to Quantum Physics Fall 2006 Logistics Lecture Room: LO 1100 (Science I, 1
Parables of Physics and a Quantum Romance
ERIC Educational Resources Information Center
Machacek, A. C.
2014-01-01
Teachers regularly use stories to amplify the concepts taught and to encourage student engagement. The literary form of a parable is particularly suitable for classroom use, and examples are given, including a longer one intended to stimulate discussion on the nature of quantum physics (and the wave-particle duality in particular).
Physics of Particle Detection 1 Claus Grupen
Siegen, Universität
Physics of Particle Detection 1 Claus Grupen Department of Physics, University of Siegen D-57068-energy, cosmic-ray, and nuclear physics [1{7]. Iden- ti#12;cation means that the mass of the particle and its charge is determined. In elementary particle physics most particles have unit charge. But in the study e
QUANTUM MECHANICS I Physics 341
Rosner, Jonathan L.
QUANTUM MECHANICS I Physics 341 KPTC 103 9:00 Â 10:20 a.m. 1 Tues., Thurs. Â Fall Quarter 1999 mechanics at the graduate level. The text for Quantum mechanics I and II will be J. J. Sakurai and Jim Napolitano, Modern Quantum Mechanics, Second Edition (Addison- Wesley, 2011). We will cover the first three
REVIEW OF PARTICLE PHYSICS* ParticleDataGroup
, Office of Science, Office of High Energy and Nuclear Physics, the Division of High Energy Physics; and by the Italian National Institute of Nuclear Physics (INFN). #12;2 Particle Data Group K. Nakamura,1,2 K1 REVIEW OF PARTICLE PHYSICS* ParticleDataGroup Abstract This biennial Review summarizes much
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.
NASA Astrophysics Data System (ADS)
Chen, Gang; Liang, Jiu-Qing
2009-05-01
In this paper we theoretically report an unconventional quantum phase transition of a simple Lipkin-Meshkov-Glick model: an interacting collective spin system without external magnetic field. It is shown that this model with integer-spin can exhibit a first-order quantum phase transition between different disordered phases, and more intriguingly, possesses a hidden supersymmetry at the critical point. However, for half-integer spin we predict another first-order quantum phase transition between two different long-range-ordered phases with a vanishing energy gap, which is induced by the destructive topological quantum interference between the intanton and anti-instanton tunneling paths and accompanies spontaneously breaking of supersymmetry at the same critical point. We also show that, when the total spin-value varies from half-integer to integer this model can exhibit an abrupt variation of Berry phase from ? to zero.
Bohmian particle trajectories contradict quantum mechanics
Michael Zirpel
2009-03-23
The Bohmian interpretation of quantum mechanics adds particle trajectories to the wave function and ensures that the probability distribution of the particle positions agrees with quantum mechanics at any time. This is not sufficient to avoid contradictions with quantum mechanics. There are correlations between particle positions at different times which cannot be reproduced with real particle trajectories. A simple rearrangement of an experimental test of the Bell-CHSH inequality demonstrates this.
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/2?; 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.
Physics as Quantum Information Processing: Quantum Fields as Quantum Automata 1
D'Ariano, Giacomo Mauro
Physics as Quantum Information Processing: Quantum Fields as Quantum Automata 1 Giacomo Mauro D) to a quantum computation? Can physics be simulated by a quantum computer? Do we believe that a quantum field on a quantum-digitalization of physics, with Quantum Theory as a special theory of information, and Physics
From Waves to Particle Tracks and Quantum Probabilities
NASA Astrophysics Data System (ADS)
Falkenburg, Brigitte
Here, the measurement methods for identifying massive charged particles are investigated. They have been used from early cosmic ray studies up to the present day. Laws such as the classical Lorentz force and Einstein's relativistic kinematics were established before the rise of quantum mechanics. Later, it became crucial to measure the energy loss of charged particles in matter. In 1930, Bethe developed a semi-classical model based on the quantum mechanics of scattering. In the early 1930s, he and others calculated the passage of charged particles through matter including pair creation and bremsstrahlung. Due to missing trust in quantum electrodynamics, however, only semi-empirical methods were employed in order to estimate the mass and charge from the features of particle tracks. In 1932, Anderson inserted a lead plate into the cloud chamber in order to determine the flight direction and charge of the `positive electron'. In the 1940s, nuclear emulsions helped to resolve puzzles about particle identification and quantum electrodynamics. Later, the measurement theory was extended in a cumulative process by adding conservation laws for dynamic properties, probabilistic quantum formulas for resonances, scattering cross sections, etc. The measurement method was taken over from cosmic ray studies to the era of particle accelerators, and finally taken back from there to astroparticle physics. The measurement methods remained the same, but in the transition from particle to astroparticle physics the focus of interest shifted. Indeed, the experimental methods of both fields explore the grounds of `new physics' in complementary ways.
Connections Between LSST Science and Particle Physics
NASA Astrophysics Data System (ADS)
Tyson, J. A.; Burchat, P.; Dubois-Felsmann, G. P.; Kahn, S. M.; Shipsey, I.; Thaler, J.
2013-01-01
We are in the midst of a revolution in physics. Observing the cosmos has provided compelling evidence for physics beyond the Standard Model of particle physics: non-zero neutrino masses, non-baryonic dark matter, dark energy and primordial inflation. Together with ordinary matter these constituents determine the structure of the Universe. The necessary, but puzzling, connection between the inner space of quantum reality and outer space of cosmic reality will enable the discovery of new particle physics through astrophysical observations and may reconcile quantum mechanics and general relativity in a new synthesis: a Standard Model of the Universe. LSST will significantly contribute to answering the following questions: What is dark energy? What is dark matter? What are the neutrino masses? Was primordial inflation responsible for the origin of large-scale structure (LSS)? Did it leave observable imprints that can shed light on the unification of the fundamental forces? Can gravity be described in a unified quantum framework with the other forces? Precision cosmological observations will enable falsification of models covering the inflationary epoch, through the “dark ages”, to the first generation of stars and galaxies, and the current cosmic acceleration. LSST will study the impact of dark energy on both the history of cosmic expansion and growth of LSS using diverse techniques based on: weak-lensing, baryon acoustic oscillations, supernovae, galaxy cluster counts and strong lensing of quasars. Inconsistencies in the results may signal deficiencies in General Relativity and the need for a new theory of gravity. Properties of dark matter will be gleaned by studying the evolution of structure and by strong-lensing of galaxies, quasars and supernovae. Precision measurements of the matter power spectra vs cosmic time will constrain the sum of neutrino masses. LSST will probe inflation using cosmic shear and the spatial power spectrum of galaxies.
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…
The past of a quantum particle
Lev Vaidman
2013-04-28
Although there is no consensus regarding the "reality" of the past of a quantum particle, in situations where there is only one trajectory with nonvanishing quantum wave of the particle between its emission and detection points, it seems "safe" to associate the past of the particle with this trajectory. A method for analyzing the past of a quantum particle according to the weak trace it leaves is proposed. Such a trace can be observed via measurements performed on an ensemble of identically pre- and post-selected particles. Examples, in which this method contradicts the above common sense description of the past of the particle are presented. It is argued that it is possible to describe the past of a quantum particle, but the naive approach has to be replaced by both forward and backward evolving quantum states.
Supersymmetry in Elementary Particle Physics
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.
8.04 Quantum Physics I, Spring 2003
Lee, Young S.
Experimental basis of quantum physics: photoelectric effect, Compton scattering, photons, Franck-Hertz experiment, the Bohr atom, electron diffraction, deBroglie waves, and wave-particle duality of matter and light. ...
EUROPEAN LABORATORY FOR PARTICLE PHYSICS CERNEP/98039
EUROPEAN LABORATORY FOR PARTICLE PHYSICS CERNÂEP/98Â039 6th March 1998 Search for Stable and Long% confidence level for particles with lifetimes longer than 10 \\Gamma6 s. (Submitted to Physics Letters B) #12
Particle statistics affects quantum decay and Fano interference.
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
Particle staining: physically based texture generation
Mistrot, Jean Michael
2004-09-30
generated particle system in a phenomenological model. The motion of these particles is controlled by physically based constraints, such as wind, gravity, mass, etc. The way in which each particle interacts with or modifies the look of the surface...
Physics 926 Introduction to Nuclear and Particle Physics
Farritor, Shane
Physics 926 Introduction to Nuclear and Particle Physics Spring 2008 Course Description We@unl.edu Office Hours: Monday 2:00-4:30 PM or by appointment (or by chance) Prerequisites Physics 917 will explore particle physics from a modern perspective, with an eye towards the new physics that we expect
Quantum Mechanics as Classical Physics
Charles Sebens
2015-04-02
Here I explore a novel no-collapse interpretation of quantum mechanics which combines aspects of two familiar and well-developed alternatives, Bohmian mechanics and the many-worlds interpretation. Despite reproducing the empirical predictions of quantum mechanics, the theory looks surprisingly classical. All there is at the fundamental level are particles interacting via Newtonian forces. There is no wave function. However, there are many worlds.
Particle Dynamics in Kicked Quantum Networks
NASA Astrophysics Data System (ADS)
Eshniyozov, Valijon; Yusupov, Jambul; Matrasulov, Davron; Ibragimov, Inomjon
Particle dynamics in a periodically driven quantum network is studied by considering delta-kicked quantum star graph is studied. Quantum dynamics is treated by solving Schrodinger equation with time-dependent boundary conditions given on graphs. Time-dependence of the average kinetic energy is analyzed. Space-time evolution of the Gaussian wave packet is treated.
A Quantum Particle Undergoing Continuous Observation
Belavkin, Viacheslav P.
A Quantum Particle Undergoing Continuous Observation V.P. Belavkin and P. Staszewskiy December 1988 the time-evolution of the unobserved quantum system) belongs to the class of phenomena called watchdog e); > 0: (2) Here a(t) = b0(t), ay (t) = by 0(t) are the annihilation and creation quantum noise operators
Quantum physics motivated neurobiology
Mershin, Andreas
2000-01-01
This research addresses the question of what role might quantum phenomena play in the brain. Recent progress in understanding brain function in terms of its basic cellular and subcellular (microtubules) components will be ...
NSDL National Science Digital Library
Basdevant, Jean-Louis
Developed by Manuel Joffre, Jean-Louis Basdevant, and Jean Dalibard at France's Ecole Polytechnique, this Web site covers topics in introductory quantum mechanics through a series of animations and simulations. Topics covered include Wave Mechanics, Quantization in one and three dimensions, Quantum Superposition in one and two dimensions, and Spin 1/2. Students will find these difficult concepts easily and intuitively illustrated. Most of the simulations are interactive, allowing visitors to change the parameters in order to better grasp the concepts.
Non-accelerator particle physics
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.
EUROPEAN LABORATORY FOR PARTICLE PHYSICS CERNEP/99130
EUROPEAN LABORATORY FOR PARTICLE PHYSICS CERNÂEP/99Â130 23 September 1999 Measurement of the W + W for new physics. Submitted to Physics Letters B #12; The OPAL Collaboration G. Abbiendi 2 , K. Ackersta# 8
EUROPEAN LABORATORY FOR PARTICLE PHYSICS CERNEP/98001
EUROPEAN LABORATORY FOR PARTICLE PHYSICS CERNÂEP/98Â001 16th January 1998 Investigation of CP for different values of sin 2fi in the physical region from \\Gamma1 to +1. (Submitted to Physics Letters B) #12
Computer tools in particle physics
Vicente, Avelino
2015-01-01
The field of particle physics is living very exciting times with a plethora of experiments looking for new physics in complementary ways. This has made increasingly necessary to obtain precise predictions in new physics models in order to be ready for a discovery that might be just around the corner. However, analyzing new models and studying their phenomenology can be really challenging. Computing mass matrices, interaction vertices and decay rates is already a tremendous task. In addition, obtaining predictions for the dark matter relic density and its detection prospects, computing flavor observables or estimating the LHC reach in certain collider signals constitutes quite a technical work due to the precision level that is currently required. For this reason, computer tools such as SARAH, MicrOmegas, MadGraph, SPheno or FlavorKit have become quite popular, and many physicists use them on a daily basis. In this course we will learn how to use these computer tools to explore new physics models and get robus...
Enrico Fermi and the Old Quantum Physics
Alberto De Gregorio; Fabio Sebastiani
2009-01-01
We outline Fermi's early attitude towards old quantum physics. We sketch out the context from which his interest for quantum physics arose, and we deal with his work on quantum statistics. We also go through the first two courses on theoretical physics he held in Rome, and his 1928 book on atomic physics.
Black hole horizons and quantum charged particles
NASA Astrophysics Data System (ADS)
Jaramillo, José Luis
2015-07-01
We point out a structural similarity between the characterization of black hole apparent horizons as stable, marginally outer trapped surfaces (MOTS) and the quantum description of a non-relativistic charged particle moving in given magnetic and electric fields on a closed surface. Specifically, the spectral problem of the MOTS-stability operator corresponds to a stationary quantum particle with a formal fine-structure constant ? of negative sign. We discuss how such analogy enriches both problems, illustrating this with the insights into the MOTS-spectral problem gained from the analysis of the spectrum of the quantum charged particle Hamiltonian.
Wave-Particle Duality and the Coherent Quantum Domain Picture
Alan M. Kadin
2006-03-08
It is proposed that the paradox of wave-particle duality in quantum mechanics may be resolved using a physical picture analogous to magnetic domains. Within this picture, a quantum particle represents a coherent region of a quantum wave with characteristic total energy, momentum, and spin. The dynamics of such a state are described by the usual linear quantum wave equations. But the coherence is maintained by a nonlinear self-interaction term that is evident only during transitions from one quantum state to another. This is analogous to the self-organizing property of domains in a ferromagnetic material, in which a single domain may appear as a stable macro-particle, but with rapid transitions between different domain configurations also possible. For the quantum case, this implies that the "collapse of the wave function" is a real dynamical physical process that occurs continuously in spacetime. This picture may also permit the resolution of apparent paradoxes associated with quantum measurement and entangled states.
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.
Quantum and classical dissipation of charged particles
Ibarra-Sierra, V.G. [Departamento de Física, Universidad Autónoma Metropolitana at Iztapalapa, Av. San Rafael Atlixco 186, Col. Vicentina, 09340 México D.F. (Mexico)] [Departamento de Física, Universidad Autónoma Metropolitana at Iztapalapa, Av. San Rafael Atlixco 186, Col. Vicentina, 09340 México D.F. (Mexico); Anzaldo-Meneses, A.; Cardoso, J.L.; Hernández-Saldaña, H. [Área de Física Teórica y Materia Condensada, Universidad Autónoma Metropolitana at Azcapotzalco, Av. San Pablo 180, Col. Reynosa-Tamaulipas, Azcapotzalco, 02200 México D.F. (Mexico)] [Área de Física Teórica y Materia Condensada, Universidad Autónoma Metropolitana at Azcapotzalco, Av. San Pablo 180, Col. Reynosa-Tamaulipas, Azcapotzalco, 02200 México D.F. (Mexico); Kunold, A., E-mail: akb@correo.azc.uam.mx [Área de Física Teórica y Materia Condensada, Universidad Autónoma Metropolitana at Azcapotzalco, Av. San Pablo 180, Col. Reynosa-Tamaulipas, Azcapotzalco, 02200 México D.F. (Mexico); Roa-Neri, J.A.E. [Área de Física Teórica y Materia Condensada, Universidad Autónoma Metropolitana at Azcapotzalco, Av. San Pablo 180, Col. Reynosa-Tamaulipas, Azcapotzalco, 02200 México D.F. (Mexico)] [Área de Física Teórica y Materia Condensada, Universidad Autónoma Metropolitana at Azcapotzalco, Av. San Pablo 180, Col. Reynosa-Tamaulipas, Azcapotzalco, 02200 México D.F. (Mexico)
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.
Student Perspectives in Quantum Physics
NASA Astrophysics Data System (ADS)
Baily, Charles; Finkelstein, Noah D.
2008-10-01
Introductory courses in classical physics are promoting in students a realist perspective, made up in part by the belief that all physical properties of a system can be simultaneously specified, and thus determined at all future times. Such a perspective can be problematic for introductory quantum physics students, who must develop new framings of epistemic and ontological resources in order to properly interpret what it means to have knowledge of quantum systems. We document this evolution in student thinking in part through pre/post instruction evaluations using the CLASS attitude survey.[1] We further characterize variations in student epistemic and ontological commitments by examining responses to an essay question, coupled with responses to supplemental quantum attitude statements. We find that, after instruction in modern physics, many students are still exhibiting a realist perspective in contexts where a quantum perspective is needed. We also find that this effect can be significantly influenced by instruction, where we observe variations for courses with differing learning goals.
Quantum Physics in One Dimension
David Logan
2004-01-01
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
Quantum optics: Wave-particle superposition
NASA Astrophysics Data System (ADS)
Adesso, Gerardo; Girolami, Davide
2012-09-01
The implementation of a quantum Wheeler's delayed-choice experiment defies the conventional boundaries set by the complementarity principle and shows photons coherently oscillating between particle and wave behaviours in a single experimental set-up.
How virtual particles generate quantum dynamics
Alberto C. de la Torre
2015-06-07
In support of the quantum field theory interpretation of quantum mechanics it is shown that two types of virtual particles $A$ and $B$ with an asymmetric interaction such that $A$ rejects (hates) $B$ and $B$ attracts (loves) $A$ have a combined distribution that satisfies Schr\\"odinger's equation. It is also shown how four virtual particles drifting, creating and destroying themselves have a combined distribution that satisfies Dirac's equation.
On the ‘Emptiness’ of Particles in Condensed-matter Physics
L. Q. English
2007-01-01
In recent years, the ontological similarities between the foundations of quantum mechanics and the emptiness teachings in\\u000a Madhyamika–Prasangika Buddhism of the Tibetan lineage have attracted some attention. After briefly reviewing this unlikely\\u000a connection, I examine ideas encountered in condensed-matter physics that resonate with this view on emptiness. Focusing on\\u000a the particle concept and emergence in condensed-matter physics, I highlight a
EUROPEAN LABORATORY FOR PARTICLE PHYSICS CERNEP/98119
EUROPEAN LABORATORY FOR PARTICLE PHYSICS CERNÂEP/98Â119 20 th July 1998 Measurement of the Average, where the first error is statistical and the second systematic. Submitted to Physics Letters B #12
EUROPEAN LABORATORY FOR PARTICLE PHYSICS CERNEP/98194
EUROPEAN LABORATORY FOR PARTICLE PHYSICS CERNÂEP/98Â194 November 23, 1998 Search for Baryon:6 and 4:4 keV respectively. (Submitted to Physics Letters B) #12; The OPAL Collaboration G. Abbiendi 2 , K
EUROPEAN LABORATORY FOR PARTICLE PHYSICS CERNEP/99084
EUROPEAN LABORATORY FOR PARTICLE PHYSICS CERNÂEP/99Â084 21 June 1999 Search for Higgs Bosons and for the particular models considered. (Accepted by Physics Letters B) #12; The OPAL Collaboration G. Abbiendi 2 , K
EUROPEAN LABORATORY FOR PARTICLE PHYSICS CERNEP/98196
EUROPEAN LABORATORY FOR PARTICLE PHYSICS CERNÂEP/98Â196 December 10, 1998 Journal Version, February is also quantified in the context of models studied. (Submitted to Physics Letters B) #12; The OPAL
EUROPEAN LABORATORY FOR PARTICLE PHYSICS CERNPPE/97168
EUROPEAN LABORATORY FOR PARTICLE PHYSICS CERNÂPPE/97Â168 19 December, 1997 Search for charged Higgs% confidence level, independent of the H + ! Ã¸ + Å¡ Ã¸ branching ratio. (Submitted to Physics Letters B) #12
EUROPEAN LABORATORY FOR PARTICLE PHYSICS CERNPPE/97159
EUROPEAN LABORATORY FOR PARTICLE PHYSICS CERNÂPPE/97Â159 16th December 1997 Measurements of the B 0 are statistical and systematic, respectively. (Submitted to Physics Letters) #12; The OPAL Collaboration K
EUROPEAN LABORATORY FOR PARTICLE PHYSICS CERNEP/98106
EUROPEAN LABORATORY FOR PARTICLE PHYSICS CERNÂEP/98Â106 3 July 1998 Journal Version, 22 September to Physics Letters) #12; The OPAL Collaboration K. Ackerstaff 8 , G. Alexander 23 , J. Allison 16 , N
EUROPEAN ORGANISATION FOR PARTICLE PHYSICS CERNPPE/93183
EUROPEAN ORGANISATION FOR PARTICLE PHYSICS CERNÂPPE/93Â183 3rd November 1993 Multiplicity to the observed e#ect. (Submitted to Physics Letters B) #12; The OPAL Collaboration R. Akers 16 , G. Alexander 23
EUROPEAN ORGANISATION FOR PARTICLE PHYSICS CERNPPE/9448
EUROPEAN ORGANISATION FOR PARTICLE PHYSICS CERNÂPPE/94Â48 22 March 1994 Search for the Minimal% confidence level. (Submitted to Physics Letters B) #12; The OPAL Collaboration R. Akers 16 , G. Alexander 23
EUROPEAN LABORATORY FOR PARTICLE PHYSICS CERNPPE/97094
EUROPEAN LABORATORY FOR PARTICLE PHYSICS CERNÂPPE/97Â094 24th July 1997 Spin alignment of leading K per hadronic Z 0 decay. To be submitted to Physics Letters B #12; The OPAL Collaboration K. Ackerstaff
EUROPEAN ORGANISATION FOR PARTICLE PHYSICS CERNPPE/9442
EUROPEAN ORGANISATION FOR PARTICLE PHYSICS CERNÂPPE/94Â42 10 March 1994 Measurement of the Ã¸ \\Gamma and the second is systematic. (Submitted to Physics Letters B) #12; The OPAL Collaboration R. Akers 16 , G
EUROPEAN LABORATORY FOR PARTICLE PHYSICS CERNEP/98013
EUROPEAN LABORATORY FOR PARTICLE PHYSICS CERNÂEP/98Â013 29 January 1998 Search for an Excess. Submitted to Physics Letters #12; The OPAL Collaboration K. Ackerstaff 8 , G. Alexander 23 , J. Allison 16
EUROPEAN LABORATORY FOR PARTICLE PHYSICS CERNPPE/97137
EUROPEAN LABORATORY FOR PARTICLE PHYSICS CERNÂPPE/97Â137 October 31, 1997 Search for the B c Meson for these processes. (Submitted to Physics Letters B) #12; The OPAL Collaboration K. Ackerstaff 8 , G. Alexander 23
EUROPEAN LABORATORY FOR PARTICLE PHYSICS CERNEP/98120
EUROPEAN LABORATORY FOR PARTICLE PHYSICS CERNÂEP/98Â120 July 20, 1998 First Measurement of Z and PYTHIA. (Accepted by Physics Letters B) #12; The OPAL Collaboration G. Abbiendi 2 , K. Ackerstaff 8 , G
EUROPEAN LABORATORY FOR PARTICLE PHYSICS CERNEP/98119
EUROPEAN LABORATORY FOR PARTICLE PHYSICS CERNÂEP/98Â119 20 th July 1998 Journal Version: 29 th Sept. Submitted to Physics Letters B #12; The OPAL Collaboration G. Abbiendi 2 , K. Ackerstaff 8 , G. Alexander 23
EUROPEAN ORGANISATION FOR PARTICLE PHYSICS CERNPPE/9443
EUROPEAN ORGANISATION FOR PARTICLE PHYSICS CERNÂPPE/94Â43 14 March 1994 Measurement of the Time. To be submitted to Physics Letters. #12; R. Akers 16 , G. Alexander 23 , J. Allison 16 , K.J. Anderson 9 , S
EUROPEAN LABORATORY FOR PARTICLE PHYSICS CERNEP/98197
EUROPEAN LABORATORY FOR PARTICLE PHYSICS CERNÂEP/98Â197 December 10, 1998 Measurement of the W Mass:32(stat:) \\Sigma 0:20(syst:) GeV. (submitted to Physics Letters B) #12; The OPAL Collaboration G. Abbiendi
EUROPEAN ORGANISATION FOR PARTICLE PHYSICS CERNPPE/91212
EUROPEAN ORGANISATION FOR PARTICLE PHYSICS CERNÂPPE/91Â212 2 December 1991 Measurement of B 0 Â â?¢ B error is statistical and the second is systematic. (submitted to Physics Letters B) #12; The OPAL
EUROPEAN LABORATORY FOR PARTICLE PHYSICS CERNEP/98013
EUROPEAN LABORATORY FOR PARTICLE PHYSICS CERNÂEP/98Â013 29 January 1998 Journal version, 27 MarchÂsection as a function of the dijet mass sum. Submitted to Physics Letters #12; The OPAL Collaboration K. Ackerstaff 8
Elementary particle physics---Experimental
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.
Quantum Field Theory of Unstable Particles
Huzihiro Araki; Yasuo Munakata; Masaaki Kawaguchi; Tetsuo Gotô
1957-01-01
Two methods of the renormalization are proposed for unstable particles. One is connected with the resonance in scattering and the other with the time development of the unstable particle state. The relation between the two formulation is discussed. Arbitrariness in the choice of the renormalization procedure comes from the uncertainty principle of the quantum mechanics.
Informational Approach to Identical Particles in Quantum Theory
Philip Goyal
2014-06-08
A remarkable feature of quantum theory is that particles with identical intrinsic properties must be treated as indistinguishable if the theory is to give valid predictions. In the quantum formalism, indistinguishability is expressed via the symmetrization postulate, which restricts a system of identical particles to the set of symmetric states (`bosons') or the set of antisymmetric states (`fermions'). However, the physical basis and range of validity of the symmetrization postulate has not been established. A well-known topological derivation of the postulate implies that its validity depends on the dimensionality of the space in which the particles move. However, this derivation relies on the labeling of indistinguishable particles, a notion that cannot be justified on an informational basis. Here we show that the symmetrization postulate can be derived by strictly adhering to the informational requirement that particles which cannot be experimentally distinguished from one another are not labeled. Our key novel postulate is the operational indistinguishability postulate, which posits that the amplitude of a process involving several indistinguishable particles is determined by the amplitudes of all possible transitions of these particles when treated as distinguishable. The symmetrization postulate follows by requiring consistency with the rest of the quantum formalism. The derivation implies that the symmetrization postulate admits no natural variants. In particular, the possibility that identical particles generically exhibit anyonic behavior in two dimensions is excluded.
Research in theoretical particle physics. Technical progress report, May 1, 1991--April 30, 1992
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)
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…
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…
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)
Education and Outreach in Particle Physics
R. Michael Barnett
2011-09-30
There are many varied programs of education and outreach in particle physics. This report for the Division of Particles and Fields of the American Physical Society 2001 meeting reviews the impact of these programs in general, and also gives several examples of ongoing programs with a primary focus on those in the US.
PHYSICS 237 SPRING 2006 Nuclear and Elementary Particle Physics
PHYSICS 237 SPRING 2006 Nuclear and Elementary Particle Physics BOOKS ON RESERVE IN CRERAR LIBRARY 1987 K. S. Krane Introductory Nuclear Physics QC777.K730 1988 Useful references P. R. Bevington and D & V. F. Weisskopf Theoretical Nuclear Physics QC776.B530 1979 L. R. Elton Introductory Nuclear Theory
International Particle Physics Masterclasses with LHC data
NASA Astrophysics Data System (ADS)
Foka, Panagiota
2014-04-01
The International Particle Physics Masterclasses is an educational activity developed by the International Particle Physics Outreach Group with the aim to bring the excitement of cutting-edge particle-physics research into the classroom. Since 2005, every year, thousands of pupils in many countries all over the world become "scientists for a day" in research centres or universities close to their schools as they are introduced to the mysteries of particle physics. In 2012, 10 000 students from 148 institutions in 31 countries took part in this popular event over a month period. The program of a typical day includes lectures that give insight to topics and methods of fundamental research followed by a "hands-on" session where students perform measurements on real data from particle-physics experiments themselves. The last two years LHC data from the ALICE, ATLAS and CMS experiments were used. A overview of the performed measurements and the employed methodology is presented.
Graphene: from materials science to particle physics
Joaquín E. Drut; Timo A. Lähde; Eero Tölö
2010-11-02
Since its discovery in 2004, graphene, a two-dimensional hexagonal carbon allotrope, has generated great interest and spurred research activity from materials science to particle physics and vice versa. In particular, graphene has been found to exhibit outstanding electronic and mechanical properties, as well as an unusual low-energy spectrum of Dirac quasiparticles giving rise to a fractional quantum Hall effect when freely suspended and immersed in a magnetic field. One of the most intriguing puzzles of graphene involves the low-temperature conductivity at zero density, a central issue in the design of graphene-based nanoelectronic components. While suspended graphene experiments have shown a trend reminiscent of semiconductors, with rising resistivity at low temperatures, most theories predict a constant or even decreasing resistivity. However, lattice field theory calculations have revealed that suspended graphene is at or near the critical coupling for excitonic gap formation due to strong Coulomb interactions, which suggests a simple and straightforward explanation for the experimental data. In this contribution we review the current status of the field with emphasis on the issue of gap formation, and outline recent progress and future points of contact between condensed matter physics and Lattice QCD.
Postdoctoral Positions (Theoretical Particle Physics, Siegen University)
Siegen, Universität
qf ett qf e Postdoctoral Positions (Theoretical Particle Physics, Siegen University) The recently and in a number of benchmark new physics scenarios, on the basis of precise and reliable theoretical predictions established DFG Research Unit FOR 1873 "Quark Flavour Physics and Effective Field Theories" at Siegen
EUROPEAN LABORATORY FOR PARTICLE PHYSICS CERNEP/98093
EUROPEAN LABORATORY FOR PARTICLE PHYSICS CERNÂEP/98Â093 16 June 1998 Search for Higgs Bosons. (Submitted to Physics Letters B) #12; The OPAL Collaboration K. Ackerstaff 8 , G. Alexander 23 , J. AllisonV with the OPAL detector at LEP. No evidence for contributions from nonÂStandard Model physics processes
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.
Quantum vortices and trajectories in particle diffraction
N. Delis; C. Efthymiopoulos; G. Contopoulos
2011-03-14
We investigate the phenomenon of the diffraction of charged particles by thin material targets using the method of the de Broglie-Bohm quantum trajectories. The particle wave function can be modeled as a sum of two terms $\\psi=\\psi_{ingoing}+\\psi_{outgoing}$. A thin separator exists between the domains of prevalence of the ingoing and outgoing wavefunction terms. The structure of the quantum-mechanical currents in the neighborhood of the separator implies the formation of an array of \\emph{quantum vortices}. The flow structure around each vortex displays a characteristic pattern called `nodal point - X point complex'. The X point gives rise to stable and unstable manifolds. We find the scaling laws characterizing a nodal point-X point complex by a local perturbation theory around the nodal point. We then analyze the dynamical role of vortices in the emergence of the diffraction pattern. In particular, we demonstrate the abrupt deflections, along the direction of the unstable manifold, of the quantum trajectories approaching an X-point along its stable manifold. Theoretical results are compared to numerical simulations of quantum trajectories. We finally calculate the {\\it times of flight} of particles following quantum trajectories from the source to detectors placed at various scattering angles $\\theta$, and thereby propose an experimental test of the de Broglie - Bohm formalism.
n-Particle Quantum Statistics on Graphs
NASA Astrophysics Data System (ADS)
Harrison, J. M.; Keating, J. P.; Robbins, J. M.; Sawicki, A.
2014-09-01
We develop a full characterization of abelian quantum statistics on graphs. We explain how the number of anyon phases is related to connectivity. For 2-connected graphs the independence of quantum statistics with respect to the number of particles is proven. For non-planar 3-connected graphs we identify bosons and fermions as the only possible statistics, whereas for planar 3-connected graphs we show that one anyon phase exists. Our approach also yields an alternative proof of the structure theorem for the first homology group of n-particle graph configuration spaces. Finally, we determine the topological gauge potentials for 2-connected graphs.
[Elementary particle physics. Annual report
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.
Quantum particle production at sudden singularities
Barrow, John D. [DAMTP, Centre for Mathematical Sciences, Cambridge University, Wilberforce Road, Cambridge CB3 0WA (United Kingdom); Batista, Antonio B.; Houndjo, Stephane [Departamento de Fisica, Universidade Federal do Espirito Santo, CEP 29060-900 Vitoria, Espirito Santo (Brazil); Fabris, Julio C. [Departamento de Fisica, Universidade Federal do Espirito Santo, CEP 29060-900 Vitoria, Espirito Santo (Brazil); GrECO, Institut d'Astrophysique de Paris-IAP, 98 bis, Boulevard Arago, 75014 Paris (France)
2008-12-15
We investigate the effects of quantum particle production on a classical sudden singularity occurring at finite time in a Friedmann universe. We use an exact solution to describe an initially radiation-dominated universe that evolves into a sudden singularity at finite time. We calculate the density of created particles exactly and find that it is generally much smaller than the classical background density and pressure which produce the sudden singularity. We conclude that, in the example studied, the quantum particle production does not lead to the avoidance or modification to the sudden future singularity. We argue that the effects of small residual anisotropies in the expansion will not change these results and show how they can be related to studies of classical particle production using a bulk viscosity. We conclude that we do not expect to see significant observable effects from local sudden singularities on our past light cone.
Analysis of Astrophysics and Particle Physics Data
California at Santa Cruz, University of
Analysis of Astrophysics and Particle Physics Data using Optimal Segmentation Jeffrey #12;Outline Goal: Detect/Characterize Local Structures Data Cells Piecewise Constant Models Fitness Functions Optimization Error analysis Interpretation Extension to Higher Dimensions #12;The Main Goal
STFC 2012 PARTICLE PHYSICS REVIEW -EXPERIMENTS AND EXPERIMENTAL CONSOLIDATED GRANTS
1 STFC 2012 PARTICLE PHYSICS REVIEW - EXPERIMENTS AND EXPERIMENTAL CONSOLIDATED GRANTS Guidelines................................................................................................. 1 Particle Physics Grants Panel ............................................................................................................................. 3 Part A: 2012 Review of Experimental Particle Physics Consolidated Grants Guidelines
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…
Paris-Sud XI, Université de
Particle Localization by Decoherence and Classical Lensing Ivo Knittel, Experimental Physics of a particle wavepacket is presented that is subject to scattering event with small momentum transfer sense notions about the quantum-classical transition are readily obtained: Decoherent free particle
Frontiers of particle beam physics
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.
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.
Quantum Key Distribution by Utilizing Four-Level Particles
Tao Yan; Fengli Yan
2010-02-09
We present a quantum key distribution protocol based on four-level particles entanglement. Furthermore, a controlled quantum key distribution protocol is proposed by utilizing three four-level particles. We show that the two protocols are secure.
Light particles A window to fundamental physics
Jaeckel, Joerg [Institute for Particle Physics Phenomenology, Durham University, Durham DH1 3LE (United Kingdom)
2010-08-30
In these proceedings we illustrate that light, very weakly interacting particles can arise naturally from physics which is fundamentally connected to very high energy scales. Searching for them therefore may give us interesting new insights into the structure of fundamental physics. The prime example is the axion.
EUROPEAN ORGANISATION FOR PARTICLE PHYSICS CERNPPE/9367
EUROPEAN ORGANISATION FOR PARTICLE PHYSICS CERNÂPPE/93Â67 30th April 1993 Search for AnomalousÂsections greater than 0.05 pb. ( Submitted to Physics Letters B ) #12; The OPAL Collaboration P.D. Acton 25 , R
EUROPEAN LABORATORY FOR PARTICLE PHYSICS CERNEP/98106
EUROPEAN LABORATORY FOR PARTICLE PHYSICS CERNÂEP/98Â106 3 July 1998 Production of Ã? c2 Mesons, the second is systematic and the third comes from branching ratio uncertainties. (To be submitted to Physics Letters) #12; The OPAL Collaboration K. Ackerstaff 8 , G. Alexander 23 , J. Allison 16 , N. Altekamp 5 , K
EUROPEAN ORGANIZATION FOR PARTICLE PHYSICS CERNPPE/9490
EUROPEAN ORGANIZATION FOR PARTICLE PHYSICS CERNÂPPE/94Â90 13 June 1994 Measurement of the Time systematic uncertainty is due to the error in the measured B 0 d lifetime. (To be submitted to Physics Letters B) #12; The OPAL Collaboration R. Akers 16 , G. Alexander 23 , J. Allison 16 , K.J. Anderson 9 , S
EUROPEAN LABORATORY FOR PARTICLE PHYSICS CERNEP / 99113
Boyer, Edmond
EUROPEAN LABORATORY FOR PARTICLE PHYSICS CERNEP / 99113 August 12, 1999 J/ and production in p suppressed. Accepted by Physics Letters B #12;1) LIP, Av. Elias Garcia 14, P-1000 Lisbon, Portugal 2) IPN, IN in interactions induced by proton [1, 2] and light ion [3] beams, at the CERN SPS. In this letter we present
Particle tunneling in a quantum corrected spacetime
NASA Astrophysics Data System (ADS)
Liu, Cheng-Zhou; Cao, Qiao-Jun
2015-01-01
Particle tunneling from a quantum corrected black hole in the gravity's rainbow was investigated by the radial trajectory method of the tunneling framework. Using the thermodynamic property of the event horizon, a simpler method for calculating the tunneling probability was shown. In this method, the Painleve coordinate transformation of spacetime and the radial trajectory equation of the tunneling particles used in the previous radial trajectory method was not used. Using the simpler method, the tunneling probability of outgoing particles, regardless of whether they are massless or massive, were calculated in a unified way. The emission rates were related to the changes of the black hole entropies before and after the emission. This implies that the emission spectrum agrees with the underling unitary theory. In addition, the Bekenstein-Hawking area for the modified black hole was established and the emission spectrum with quantum corrections was discussed.
Particle Physics in a Season of Change
Chris Quigg
2012-01-01
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 12 fb¹ of {bar p}p interactions delivered to CDF and D0 at s = 1.96
Non-accelerator Particle Physics
R N Mohapatra
1996-01-01
The recent and collider experiments have made it abundantly clear that all known physics below the energy of 100 GeV or so is successfully described in terms of a spontaneously broken local gauge field theory based on the symmetry group , the standard model of electroweak interactions. The progress in our understanding is perhaps more spectacular in the electroweak arena
Critique of ``Quantum Enigma: Physics Encounters Consciousness''
NASA Astrophysics Data System (ADS)
Nauenberg, Michael
2007-11-01
The central claim that understanding quantum mechanics requires a conscious observer, which is made by B. Rosenblum and F. Kuttner in their book “Quantum Enigma: Physics encounters consciousness”, is shown to be based on various misunderstandings and distortions of the foundations of quantum mechanics.
Model Fitting in Particle Physics
Dolan, Matthew
2008-06-27
, Dolan, Weber The Standard Model and Beyond From The Standard Model To String Theory Global Fitting Probing Parameter Space. MCMC Results Summary Scanning Parameter Space. Naïve: scan through a grid Plus side: Control of ranges, step size? know where we... . MCMC Results Summary Signals of the LVS Smoking gun(?):Ratio of gaugino masses 6 : 2 : 1.5? 2 Minimal supergravity 6 : 2 : 1. Other masses: 95% c.l. below 1.5TeV mh < 120GeV Good for finding SUSY at LHC! Higgs particle: not seen for a few years. MCMC...
Quantum Security for the Physical Layer
Humble, Travis S [ORNL
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.
Quantum Security for the Physical Layer
Travis S. Humble
2014-07-16
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.
Research on elementary particle physics
NASA Astrophysics Data System (ADS)
Holloway, L. E.; Ohalloran, 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; and (8) Electronics systems development.
Process Physics: Inertia, Gravity and the Quantum
Reginald T. Cahill
2001-10-29
Process Physics models reality as self-organising relational or semantic information using a self-referentially limited neural network model. This generalises the traditional non-process syntactical modelling of reality by taking account of the limitations and characteristics of self-referential syntactical information systems, discovered by Goedel and Chaitin, and the analogies with the standard quantum formalism and its limitations. In process physics space and quantum physics are emergent and unified, and time is a distinct non-geometric process. Quantum phenomena are caused by fractal topological defects embedded in and forming a growing three-dimensional fractal process-space. Various features of the emergent physics are briefly discussed including: quantum gravity, quantum field theory, limited causality and the Born quantum measurement metarule, inertia, time-dilation effects, gravity and the equivalence principle, a growing universe with a cosmological constant, black holes and event horizons, and the emergence of classicality.
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.
Test particle in a quantum gas
Vacchini, Bassano
2001-06-01
A master equation with a Lindblad structure is derived, which describes the interaction of a test particle with a macroscopic system and is expressed in terms of the operator valued dynamic structure factor of the system. In the case of a free Fermi or Bose gas the result is evaluated in the Brownian limit, thus obtaining a single generator master equation for the description of quantum Brownian motion in which the correction due to quantum statistics is explicitly calculated. The friction coefficients for Boltzmann and Bose or Fermi statistics are compared.
Links between quantum physics and thought.
Robson, Barry
2009-01-01
Quantum mechanics (QM) provides a variety of ideas that can assist in developing Artificial Intelligence for healthcare, and opens the possibility of developing a unified system of Best Practice for inference that will embrace both QM and classical inference. Of particular interest is inference in the hyperbolic-complex plane, the counterpart of the normal i-complex plane of basic QM. There are two reasons. First, QM appears to rotate from i-complex Hilbert space to hyperbolic-complex descriptions when observations are made on wave functions as particles, yielding classical results, and classical laws of probability manipulation (e.g. the law of composition of probabilities) then hold, whereas in the i-complex plane they do not. Second, i-complex Hilbert space is not the whole story in physics. Hyperbolic complex planes arise in extension from the Dirac-Clifford calculus to particle physics, in relativistic correction thereby, and in regard to spinors and twisters. Generalization of these forms resemble grammatical constructions and promote the idea that probability-weighted algebraic elements can be used to hold dimensions of syntactic and semantic meaning. It is also starting to look as though when a solution is reached by an inference system in the hyperbolic-complex, the hyperbolic-imaginary values disappear, while conversely hyperbolic-imaginary values are associated with the un-queried state of a system and goal seeking behavior. PMID:19745485
8.05 Quantum Physics II, Fall 2004
Stewart, Iain
Together, this course and 8.06: Quantum Physics III cover quantum physics with applications drawn from modern physics. Topics covered in this course include the general formalism of quantum mechanics, harmonic oscillator, ...
Theoretical particle physics, Task A
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.
To Photon Concept and to Physics of Quantum Absorption Process
Dmitri Yerchuck; Yauhen Yerchak; Alla Dovlatova; Vyacheslav Stelmakh; Felix Borovik
2014-06-03
The status of the photon in the modern physics was analysed. Within the frames of the Standard Model of particle physics the photon is considered to be the genuine elementary particle, being to be the messenger of the electromagnetic interaction to which are subject charged particles. In contrast, the experts in quantum electodynamics (in particular, in quantum optics) insist, that the description of an photon to be the particle is impossible. The given viewpoint was carefully analysed and its falseness was proved. The expression for a photon wave function is presented. So, the status of the photon in quantum electodynamics was restored. The physics of a quantum absorption process is analysed. It is argued in accordance with Dirac guess, that the photon revival takes place by its absorption. Being to be a soliton, it seems to be keeping safe after an energy absorption in a pinned state, possessing the only by spin. It is shown, that the time of the transfer of absorbing systems in an excited state is finite and moreover, that it can govern the stationary signal registered. The given result is significant for the all stationary spectroscopy, in which at present the transfer of absorbing systems in an excited state is considered to be instantaneous.
Quarked! - Adventures in Particle Physics Education
NASA Astrophysics Data System (ADS)
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 introduced until high school or university.1,2 Many of these concepts can be made accessible to younger students when presented in a fun and engaging way. Informal science institutions are in an ideal position to communicate new and challenging science topics in engaging and innovative ways and offer a variety of educational enrichment experiences for students that support and enhance science learning.3 Quarked!™ Adventures in the Subatomic Universe, a National Science Foundation EPSCoR-funded particle physics education program, provides classroom programs and online educational resources.
Particles and Nuclei as Quantum Slings
I. M. Dremin; V. I. Manko
1997-11-24
Rotation of such objects as an atomic nucleus or a chromodynamical string can result in specific effects in scattering processes and multiparticle production. Secondary fragments of the rotating nucleus or of the decaying string can move like stones thrown from a sling. That would be detected as the azimuthal asymmetry of particle distributions in individual events. Non-classical states of the created particles like the Schr"\\{o}dinger cats are produced. Some classical and quantum-mechanical estimates of possible effects are given. Experimental facts which can be used for their verification are discussed.
What is a Particle in Classical Physics? A Wave?
NASA Astrophysics Data System (ADS)
Mickens, Ronald E.
2005-11-01
The concepts of ``particle" and ``wave" play important roles in quantum mechanics in that a given microscopic system can, under the proper circumstances, display properties of each.ootnotetextA Messiah, Quantum Mechanics, Vols. I and II (Wiley, 1961). However, these categories have their genesis in classical mechanicsootnotetextH. Goldstein, Classical Mechanics (Addison-Wesley, 1980, 2nd edition). and we must turn to this area to understand what they mean. In particular, it must be clearly understood that these concepts are idealistic representations of physical phenomena and, as a consequence, each may not correspond to any actual physical system. We discuss the definition of ``particle'' from the perspective of how it has been defined in standard textbooks and carry out a similar analysis for the notion of ``wave.'' We then define ``particle'' and ``wave'' within the context of classical mechanics by means of their respective equations of motion. The general (tentative) conclusion is that within the framework of classical mechanics the concepts of ``particle'' and ``wave'' systems may be unambiguously defined.
Particle physics with the LHC data
Hagiwara, Kaoru [KEK Theory Center and Sokendai, Tsukuba 305-0801 (Japan)
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.
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.
Krieger, Peter
Introduction to Nuclear and Particle Physics PHY357 1 Better name is probably Introduction to Subatomic physics: Emphasis is on particle physics; nuclear physics is simply particle physics at relatively particle MX Force Effective Strength Physical Process Strong 100 Nuclear binding Electromagnetic 10
Particle creation from the quantum stress tensor
Firouzjaee, Javad T
2015-01-01
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 back-reaction 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. It will be shown that in the case of general spherically symmetric black holes that have a \\emph{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 [25]. 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 tempera...
Research in Theoretical Particle Physics
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.
Flavor Democracy in Particle Physics
Saleh Sultansoy
2006-10-21
The flavor democracy hypothesis 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.eq. 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.
Flavor Democracy in Particle Physics
Sultansoy, Saleh [Gazi University, Dept. of Physics, 06500 Teknikokullar, Ankara (Turkey); Academy of Sciences, Institute of Physics, H. Cavid Av. 33, Baku (Azerbaijan)
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.
Flavor Democracy in Particle Physics
Sultansoy, S
2007-01-01
The flavor democracy hypothesis 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.eq. 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...
Particle Physics Outreach to Secondary Education
Bardeen, Marjorie G.; /Fermilab; Johansson, K.Erik; /Stockholm U.; 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.
Gerhard Groessing
2008-08-01
Einstein's objection against both the completeness claim of the orthodox version and the Bohmian interpretation of quantum theory, using the example of a 'particle in a box', is reiterated and resolved. This is done by proving that the corresponding quantum mechanical states exactly match classical analogues. The latter are shown to result from the recently elaborated physics of diffusion waves.
Strange particle nuclear physics: Workshop summary
Dover, C.B.
1993-03-01
Several sessions of the Working Group on Hadronic and Nuclear Spectroscopy dealt with different aspects of strange particle nuclear physics, including hypernuclear spectroscopy, strange dibaryons, and K{sup +} interactions with nuclei. Recent developments in this area are summarized here, and open questions are identified. Some prospects for optimum use of existing facilities, as well as the desired characteristics of future ones, are discussed.
Strange particle nuclear physics: Workshop summary
Dover, C.B.
1993-03-01
Several sessions of the Working Group on Hadronic and Nuclear Spectroscopy dealt with different aspects of strange particle nuclear physics, including hypernuclear spectroscopy, strange dibaryons, and K[sup +] interactions with nuclei. Recent developments in this area are summarized here, and open questions are identified. Some prospects for optimum use of existing facilities, as well as the desired characteristics of future ones, are discussed.
Theoretical Studies in Elementary Particle Physics
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.
Current Experiments in Particle Physics (September 1996)
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.
Quantum Physics of Atoms and Materials
Moeck, Peter
299 9 Quantum Physics of Atoms and Materials The first postulate enunciates the existence: Physics for the Internet Age 9.1 ATOMS, CRYSTALS, AND COMPUTERS Modern computers are made? The answer lies in atomic physics, namely in the motion of electrons within atoms. Between 1900 and 1930
Shu Tanaka; Ryo Tamura
2012-04-13
In this paper, we review some features of quantum annealing and related topics from viewpoints of statistical physics, condensed matter physics, and computational physics. We can obtain a better solution of optimization problems in many cases by using the quantum annealing. Actually the efficiency of the quantum annealing has been demonstrated for problems based on statistical physics. Then the quantum annealing has been expected to be an efficient and generic solver of optimization problems. Since many implementation methods of the quantum annealing have been developed and will be proposed in the future, theoretical frameworks of wide area of science and experimental technologies will be evolved through studies of the quantum annealing.
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.…
Quantum physics of molecular magnets
NASA Astrophysics Data System (ADS)
Jaafar, Reem
In this thesis we focus on various aspects of quantum physics in molecular magnets, in particular, in Mn12-acetate. This thesis is divided into three parts. In the first part, we present a review on molecular magnets. Since Mn 12-acetate has a large spin (equal to 10), the theory of tunneling of a large spin is discussed as well as the early experiments that were performed two decades ago and which has shown spin tunneling, in particular, the ones that were performed on gamma-Fe2O3 and on antiferromagnetic ferritin. Then, the first experiments that presented evidence on spin tunneling in Mn12-acetate are outlined in detail. Magnetic hysteresis curves are shown and Landau-Zener effect in molecular magnets is discussed. Quantum classical crossover between thermally assisted and pure quantum tunneling regimes is described. Finally, magnetic avalanches are introduced: they are another feature of the magnetization curve in Mn12-Acetate where there is a sudden reversal in the magnetization. We exploit the first two experiments performed to elucidate the nature of magnetic avalanches in Mn12-acetate and the theory developed as a result of these experiments. In the second part of this thesis, we focus on three of my publications on quantum magneto-mechanical effects. First, a recent experiment on Einstein-de Haas effect in a NiFe film deposited on a microcantilever is discussed. The cantilever was placed inside a coil that generated an ac magnetic field. Oscillation of the cantilever was measured by a fiber-optic interferometer positioned above the tip of the cantilever. When the frequency of the ac field matched the resonance frequency of the cantilever the amplitude of the oscillations was about 3 nm. The data were analyzed within a model that replaced the mechanical torque due to change in the magnetization with the effect of the periodic force acting on the fictitious point mass at the free end of the cantilever so this model did not account for the microscopic dynamics of the Einstein-de Haas effect. This motivated us to develop a more rigorous theoretical framework for the description of the dynamics of the Einstein-de Haas effect that we applied to the problem of the magnetic cantilever. We then study the quantum dynamics of a magnetic molecule deposited on a microcantilever. Amplitude and frequencies of the coupled magneto-mechanical oscillations have been computed. We show that oscillations of the spin and the cantilever occur independently at frequencies Delta/h and o n respectively, unless these two frequencies come very close to each other. The results show that the splitting delta has no free parameters and that for a given resonance, Delta = hon, the relative splitting delta depends only on the position of the molecule on the cantilever. We then show that existing experimental techniques permit observation of the driven coupled oscillations of the spin and the cantilever, as well as of the splitting of the mechanical modes of the cantilever caused by spin tunneling. Finally, the dynamics of a magnetic molecule bridged between two conducting leads is investigated. We start by reviewing various experiments performed when there is a weak coupling between the molecule and the leads and when there is a strong coupling which results in the Kondo effect. Experimental efforts were mainly motivated to measure the electronic current through a single molecule. We study the dynamics of the total angular momentum that couples spin tunneling to the mechanical rotations. We show that the Landau-Zener spin transition produced by the time-dependent magnetic field generates a unique pattern of mechanical oscillations that can be detected by measuring the electronic tunneling current through the molecule. In the last and final part, we present our numerical work to describe quantum magnetic deflagration in Mn12-acetate. This part is related to magnetic deflagration as discussed in part I of this thesis. The focus is on the quantum features of magnetic deflagration which are exhibited by the maxima in the speed of deflagration front a
Energetic particle physics issues for ITER
Cheng, C.Z.; Budny, R.; Fu, G.Y. [and others
1996-12-31
This paper summarizes our present understanding of the following energetic/alpha particle physics issues for the 21 MA, 20 TF coil ITER Interim Design configuration and operational scenarios: (a) toroidal field ripple effects on alpha particle confinement, (b) energetic particle interaction with low frequency MHD modes, (c) energetic particle excitation of toroidal Alfven eigenmodes, and (d) energetic particle transport due to MHD modes. TF ripple effects on alpha loss in ITER under a number of different operating conditions are found to be small with a maximum loss of 1%. With careful plasma control in ITER reversed-shear operation, TF ripple induced alpha loss can be reduced to below the nominal ITER design limit of 5%. Fishbone modes are expected to be unstable for {beta}{sub {alpha}} > 1%, and sawtooth stabilization is lost if the ideal kink growth rate exceeds 10% of the deeply trapped alpha precessional drift frequency evaluated at the q = 1 surface. However, it is expected that the fishbone modes will lead only to a local flattening of the alpha profile due to small banana size. MHD modes observed during slow decrease of stored energy after fast partial electron temperature collapse in JT-60U reversed-shear experiments may be resonant type instabilities; they may have implications on the energetic particle confinement in ITER reversed-shear operation. From the results of various TAE stability code calculations, ITER equilibria appear to lie close to TAE linear stability thresholds. However, the prognosis depends strongly on q profile and profiles of alpha and other high energy particles species. If TAE modes are unstable in ITER, the stochastic diffusion is the main loss mechanism, which scales with ({delta}B{sub r}/B){sup 2}, because of the relatively small alpha particle banana orbit size. For isolated TAE modes the particle loss is very small, and TAE modes saturate via the resonant wave-particle trapping process at very small amplitude.
Quantum mechanics as a complete physical theory
D. A. Slavnov
2002-11-10
We show that the principles of a ''complete physical theory'' and the conclusions of the standard quantum mechanics do not irreconcilably contradict each other as is commonly believed. In the algebraic approach, we formulate axioms that allow constructing a renewed mathematical scheme of quantum mechanics. This scheme involves the standard mathematical formalism of quantum mechanics. Simultaneously, it contains a mathematical object that adequately describes a single experiment. We give an example of the application of the proposed scheme.
Multiple-Particle Interference and Quantum Error Correction
Andrew Steane
1996-01-01
The concept of multiple-particle interference is discussed, using insights provided by the classical theory of error correcting codes. This leads to a discussion of error correction in a quantum communication channel or a quantum computer. Methods of error correction in the quantum regime are presented, and their limitations assessed. A quantum channel can recover from arbitrary decoherence of x qubits
Novel quantum numbers in condensed matter physics
J. R. Schrieffer
2004-01-01
The physics understanding novel quantum numbers in condensed matter physics are discussed. Examples are given from the fields of conducting quasi-one-dimensional conductors 3He–A and the fractional quantum Hall effect. A common feature of these systems is a symmetry breaking whose under parameter describes a discrete symmetry breaking. This lead to flow of charge in the vacuum without excitation of carriers
Clarissa Ai Ling Lee
2014-06-21
The dissertation brings together approaches across the fields of physics, critical theory, literary studies, philosophy of physics, sociology of science, and history of science to synthesize a hybrid approach for instigating more rigorous and intense cross-disciplinary interrogations between the sciences and the humanities. There are two levels of conversations going on in the dissertation; at the first level, the discussion is centered on a critical historiography and philosophical implications of the discovery Higgs boson in relation to its position at the intersection of old (current) and the potential for new possibilities in quantum physics; I then position my findings on the Higgs boson in connection to the double-slit experiment that represents foundational inquiries into quantum physics, to demonstrate the bridge between fundamental physics and high energy particle physics. The conceptualization of the variants of the double-slit experiment informs the aforementioned critical comparisons. At the second level of the conversation, theories are produced from a close study of the physics objects as speculative engine for new knowledge generation that are then reconceptualized and re-articulated for extrapolation into the speculative ontology of hard science fiction, particularly the hard science fiction written with the double intent of speaking to the science while producing imaginative and socially conscious science through the literary affordances of science fiction. The works of science fiction examined here demonstrate the tension between the internal values of physics in the practice of theory and experiment and questions on ethics, culture, and morality.
Advanced analysis methods in particle physics
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.
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.
The Quantum Gravity wars: Quantum Physics confronts
Visser, Matt
. · The end user does not need to know the details... 5 #12;Special relativistic technology: · Lasers. (Pointers; CD's; CD-ROM) · Satellite time delays. (Phone system) · Physical size of computers. · Length
A Theory of Physical Quantum Computation: The Quantum Computer Condition
Gerald Gilbert; Michael Hamrick; F. Javier Thayer
2005-07-20
In this paper we present a new unified theoretical framework that describes the full dynamics of quantum computation. Our formulation allows any questions pertaining to the physical behavior of a quantum computer to be framed, and in principle, answered. We refer to the central organizing principle developed in this paper, on which our theoretical structure is based, as the *Quantum Computer Condition* (QCC), a rigorous mathematical statement that connects the irreversible dynamics of the quantum computing machine, with the reversible operations that comprise the quantum computation intended to be carried out by the quantum computing machine. Armed with the QCC, we derive a powerful result that we call the *Encoding No-Go Theorem*. This theorem gives a precise mathematical statement of the conditions under which fault-tolerant quantum computation becomes impossible in the presence of dissipation and/or decoherence. In connection with this theorem, we explicitly calculate a universal critical damping value for fault-tolerant quantum computation. In addition we show that the recently-discovered approach to quantum error correction known as "operator quantum error-correction" (OQEC) is a special case of our more general formulation. Our approach furnishes what we will refer to as "operator quantum fault-tolerance" (OQFT). In particular, we show how the QCC allows one to derive error thresholds for fault tolerance in a completely general context. We prove the existence of solutions to a class of time-dependent generalizations of the Lindblad equation. Using the QCC, we also show that the seemingly different circuit, graph- (including cluster-) state, and adiabatic paradigms for quantum computing are in fact all manifestations of a single, universal paradigm for all physical quantum computation.
Thermal equilibrium of two quantum Brownian particles
Valente, D. M.; Caldeira, A. O. [Departamento de Fisica da Materia Condensada, Instituto de Fisica Gleb Wataghin, Universidade Estadual de Campinas, CEP 13083-970, Campinas-SP (Brazil)
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.
Current experiments in elementary particle physics. Revised
Galic, H. [Stanford Univ., CA (United States). Stanford Linear Accelerator Center; Wohl, C.G.; Armstrong, B. [Lawrence Berkeley Lab., CA (United States); Dodder, D.C. [Los Alamos National Lab., NM (United States); Klyukhin, V.I.; Ryabov, Yu.G. [Inst. for High Energy Physics, Serpukhov (Russian Federation); Illarionova, N.S. [Inst. of Theoretical and Experimental Physics, Moscow (Russian Federation); Lehar, F. [CEN Saclay, Gif-sur-Yvette (France); Oyanagi, Y. [Univ. of Tokyo (Japan). Faculty of Sciences; Olin, A. [TRIUMF, Vancouver, BC (Canada); Frosch, R. [Paul Scherrer Inst., Villigen (Switzerland)
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.
Current experiments in elementary particle physics. Revision
Galic, H. [Stanford Linear Accelerator Center, Menlo Park, CA (United States); Armstrong, F.E. [Lawrence Berkeley Lab., CA (United States); von Przewoski, B. [Indiana Univ. Cyclotron Facility, Bloomington, IN (United States)] [and others
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.
Neutrinoless Double Beta Decay in Particle Physics
Werner Rodejohann
2010-11-22
Neutrinoless double beta decay is a process of fundamental importance for particle physics. It can be mediated by light massive Majorana neutrinos (standard interpretation) or by something else (non-standard interpretations). We review its dependence on the neutrino parameters, its complementarity to other observables sensitive to neutrino mass, and emphasize its ability to distinguish different neutrino mass models. Then we discuss mechanisms different from light Majorana neutrino exchange, and show what can be learned from those and how they could be tested.
An Introduction to Neutrosophic Probability Applied in Quantum Physics
NASA Astrophysics Data System (ADS)
Smarandache, Florentin
2009-05-01
In this paper we generalizes the classical probability and imprecise probability to the notion of neutrosophic probability in order to be able to model Heisenberg's Uncertainty Principle of a particle's behavior, Schr"odinger's Cat Theory, and the state of bosons which do not obey Pauli's Exclusion Principle (in quantum physics). Neutrosophic probability is close related to neutrosophic logic and neutrosophic set, and etymologically derived from neutrosophy.
An Introduction to the Neutrosophic Probability Applied in Quantum Physics
Florentin Smarandache
2000-10-10
In this paper one generalizes the classical probability and imprecise probability to the notion of "neutrosophic probability" in order to be able to model Heisenberg's Uncertainty Principle of a particle's behavior, Schr"dinger's Cat Theory, and the state of bosons which do not obey Pauli's Exclusion Principle (in quantum physics). Neutrosophic probability is close related to neutrosophic logic and neutrosophic set, and etymologically derived from "neutrosophy".
Hobson, Art
quantum physics in introductory general physics courses Art Hobson Department of Physics, University-particle nature of radiation and matter that is central to quantum physics, but also the symmetry between-relativistic quantum mechanics in introductory courses, including non-mathematical courses for non-scientists, math
Current experiments in particle physics - particle data group
Galic, H. [Stanford Univ., CA (United States). Stanford Linear Accelerator Center; Lehar, F. [Centre d`Etudes Nucleaires de Saclay, Gif-sur-Yvette (France); Kettle, P.R. [Paul Scherrer Institute, Villigen (Switzerland)] [and others
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.
Physical Interpretations of Nilpotent Quantum Mechanics
Peter Rowlands
2010-01-01
Nilpotent quantum mechanics provides a powerful method of making efficient calculations. More importantly, however, it provides insights into a number of fundamental physical problems through its use of a dual vector space and its explicit construction of vacuum. Physical interpretation of the nilpotent formalism is discussed with respect to boson and baryon structures, the mass-gap problem, zitterbewgung, Berry phase, renormalization,
Quantum Metrology and Fundamental Physical Constants
J H Sanders
1984-01-01
The NATO Advanced Study Institute held at Erice, Sicily, in November 1981 brought together specialists in precise measurement to present a tutorial introduction to quantum metrology and the measurement of the fundamental physical constants.Ever since the evolution of experimental physics as a scientific pursuit the measurement of the values of quantities accepted to be constants of nature has commanded the
Faculty Position in Experimental Particle Physics Department of Physics, Carleton University
Faculty Position in Experimental Particle Physics Department of Physics, Carleton University-track faculty position in experimental particle physics at the rank of Assistant Professor in the Department areas of experimental particle physics are encouraged to apply. The Department has a strong particle
Anderson Localization for a Multi-Particle Quantum Graph
Mostafa Sabri
2013-07-18
We study a multi-particle quantum graph with random potential. Taking the approach of multiscale analysis we prove exponential and strong dynamical localization of any order in the Hilbert-Schmidt norm near the spectral edge. Apart from the results on multi-particle systems, we also prove Lifshitz-type asymptotics for single-particle systems. This shows in particular that localization for single-particle quantum graphs holds under a weaker assumption on the random potential than previously known.
An approach to the formalism of the Standard Model of Particle Physics
O. E. Casas B; A. M. Raba P.; N. Poveda T
2010-05-03
So far, the Standard Model of particle physics (SM) describes the phenomenology observed in high energy physics. In the Large Hadron Collider (LHC) is expected to find the Higgs boson, which is an essential part of SM; also expects to see new particles or deviations from the SM, which would be evidence of other truly fundamental theory. Consequently, a clear understanding of the SM and, in general, quantum field theory is of great importance for particle physics, however, students face a formalism and a set of concepts with which they are unfamiliar. This paper shows how to make an approach to SM to introduce students to the formalism and some fundamental concepts.
Counting statistics of many-particle quantum walks
Mayer, Klaus; Tichy, Malte C.; Buchleitner, Andreas [Physikalisches Institut, Albert-Ludwigs-Universitaet Freiburg, Hermann-Herder Strasse 3, D-79104 Freiburg (Germany); Mintert, Florian [Physikalisches Institut, Albert-Ludwigs-Universitaet Freiburg, Hermann-Herder Strasse 3, D-79104 Freiburg (Germany); Freiburg Institute for Advanced Studies, Albert-Ludwigs-Universitaet Freiburg, Albertstrasse 19, D-79104 Freiburg (Germany); Konrad, Thomas [Quantum Research Group, School of Physics and National Institute of Theoretical Physics, University of KwaZulu-Natal, Private Bag X54001, Durban 4000 (South Africa)
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.
Hiroomi Umezawa
1984-01-01
Throughout the course of its development in the past four decades quantum field theory has gradually acquired a very rich structure (much richer in fact than it was originally intended) and now provides us with an effective method in the analysis of many diverse areas of physics; condensed matter physics, high energy particle physics general relativity and cosmology are among
FINAL REPORT: GEOMETRY AND ELEMENTARY PARTICLE PHYSICS
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.
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)
Postdoctoral Position (Theoretical Particle Physics, Dortmund Technical University )
Siegen, Universität
qf ett qf e Postdoctoral Position (Theoretical Particle Physics, Dortmund Technical University in the Theoretical Particle Physics group at Dortmund, starting fall 2013; earlier starting dates are possible and beyond the Standard Model. Information about the Theoretical Particle Physics group at Dortmund can
Accelerators | Photon Science | Particle Physics Deutsches Elektronen-Synchrotron
Accelerators | Photon Science | Particle Physics Deutsches Elektronen-Synchrotron A Research Centre of the Helmholtz Association PARTICLE PHYSICS· DESY has openings for: DESY-Fellowships (f/m) DESY DESY is one accelerators and detectors for photon science and particle physics. The position Fellows in experimental
Accelerators | Photon Science | Particle Physics Deutsches Elektronen-Synchrotron
Accelerators | Photon Science | Particle Physics Deutsches Elektronen-Synchrotron A Research Centre of the Helmholtz Association PARTICLE PHYSICS· DESY has openings for: DESY-Fellowships (f/m) DESY DESY is one of the world's leading research centres for photon science, particle and astroparticle physics as well
STFC 2009 PARTICLE PHYSICS REVIEW -EXPERIMENTS AND EXPERIMENTAL ROLLING GRANTS
STFC 2009 PARTICLE PHYSICS REVIEW - EXPERIMENTS AND EXPERIMENTAL ROLLING GRANTS Guidelines for Applicants CONTENTS PAGE Introduction and Timetable 1 Particle Physics Grants Panel 1 Enquiries 2 Part A 2009 Review of Experimental Particle Physics Rolling Grants 3 Guidelines for Applicants 1 Procedures
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.
Applied Physics Graduate Program The Rice Quantum Institute
Richards-Kortum, Rebecca
94 Applied Physics Graduate Program The Rice Quantum Institute Participating Faculty This program and the engineering divisions at Rice and overseen by the Rice Quantum Institute (RQI), the Applied Physics Program Quantum Mechanics I (PHYS 521 or CHEM 530) Quantum Mechanics II or Statistical Physics (PHYS 522 or PHYS
Tests of the particle physics-physical cosmology interface
Schramm, D.N. [Chicago Univ., IL (United States)]|[Fermi National Accelerator Lab., Batavia, IL (United States)
1993-01-01
Three interrelated interfaces of particle physics and physical cosmology are discussed: (1) inflation and other phase transitions; (2) Big Bang Nucleosynthesis (and also the quark-hadron transition); and (3) structure formation (including dark matter). Recent observations that affect each of these topics are discussed. Topic number 1 is shown to be consistent with the COBE observations but not proven and it may be having problems with some age-expansion data. Topic number 2 has now been well-tested and is an established ``pillar`` of the Big Bang. Topic number 3 is the prime arena of current physical cosmological activity. Experiments to resolve the current exciting, but still ambiguous, situation following the COBE results are discussed.
Tests of the particle physics-physical cosmology interface
Schramm, D.N. (Chicago Univ., IL (United States) Fermi National Accelerator Lab., Batavia, IL (United States))
1993-01-01
Three interrelated interfaces of particle physics and physical cosmology are discussed: (1) inflation and other phase transitions; (2) Big Bang Nucleosynthesis (and also the quark-hadron transition); and (3) structure formation (including dark matter). Recent observations that affect each of these topics are discussed. Topic number 1 is shown to be consistent with the COBE observations but not proven and it may be having problems with some age-expansion data. Topic number 2 has now been well-tested and is an established pillar'' of the Big Bang. Topic number 3 is the prime arena of current physical cosmological activity. Experiments to resolve the current exciting, but still ambiguous, situation following the COBE results are discussed.
TOPICS IN THE PHYSICS OF PARTICLE ACCELERATORS
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 machines with which you will be involved in the years to come. Perhaps, we can even turn your frustration with the inadequacy of these machines into marvel at the performance of the accelerators. At the least, we hope to convince you that the accelerators are central, not peripheral, to our science and that the physics of such machines is both fascinating and sophisticated. The plan is the following: First I will give two lectures on basic accelerator physics; then you will hear two lectures on the state of the art, present limitations, the specific parameters of LEP, HERA, TEV2 and SLC, and some extrapolation to the next generation of machines such as the Large Hadron Collider (LHC), Superconducting Super Collider (SSC), and Large Linear Colliders; finally, I will give two lectures on new acceleration methods.
Bohmian Particle Trajectories in Relativistic Bosonic Quantum Field Theory
Hrvoje Nikolic
2004-01-01
We study the de Broglie–Bohm interpretation of bosonic relativistic quantum mechanics and argue that the negative densities and superluminal velocities that appear in this interpretation do not lead to inconsistencies. After that, we study particle trajectories in bosonic quantum field theory. A new continuously changing hidden variable - the effectivity of a particle (a number between 0 and 1) -
On the angular momentum of a system of quantum particles
Paris-Sud XI, Université de
On the angular momentum of a system of quantum particles O. Chavoya-Aceves 5610 North 78th Dr, Glendale, AZ USA chavoyao@gmail.com October 3, 2013 Abstract The properties of angular momentum and its of angular momentum of a quantum system of particles into orbital angular momentum plus intrinsic angular
On the angular momentum of a system of quantum particles
On the angular momentum of a system of quantum particles O. Chavoya-Aceves Glendale Community College, Phoenix, AZ, USA chavoyao@gmail.com August 22, 2014 Abstract The properties of angular momentum experiment and gauge invariance. The separation of angular momentum of a quantum system of particles
The Underlying Physics in Wetted Particle Collisions
NASA Astrophysics Data System (ADS)
Donahue, Carly; Hrenya, Christine; Davis, Robert
2008-11-01
Wetted granular particles are relevant in many industries including the pharmaceutical and chemical industries and has applications to granulation, filtration, coagulation, spray coating, drying and pneumatic transport. In our current focus, we investigate the dynamics of a three-body normal wetted particle collision. In order to conduct collisions we use an apparatus called a ``Stokes Cradle,'' similar to the Newton's Cradle (desktop toy) except that the target particles are covered with oil. Here, we are able to vary the oil thickness, oil viscosity, and material properties. With a three particle collision there are four possible outcomes: fully agglomerated (FA); Newton's Cradle (NC), the striker and the first target ball are agglomerated and the last target ball is separated; Reverse Newton's Cradle (RNC), the striker is separated and the two targets are agglomerated; and fully separated (FS). Varying the properties of the collisions, we have observed all four outcomes. We use elastohydrodynamics as a theoretical basis for modeling the system. We also have considered the glass transition of the oil as the pressure increases upon impact and the cavitation of the oil as the pressure drops below the vapor pressure upon rebound. A toy model has been developed where the collision is modeled as a series of two-body collisions. A qualitative agreement between the toy model and experiments gives insight into the underlying physics.
School on Particle Physics, Gravity and Cosmology
NASA Astrophysics Data System (ADS)
Brandenberger, Robert
These lectures present a brief review of inflationary cosmology, provide an overview of the theory of cosmological perturbations, and then focus on the conceptual problems of the current paradigm of early universe cosmology, thus motivating an exploration of the potential of string theory to provide a new paradigm. Specifically, the string gas cosmology model is introduced, and a resulting mechanism for structure formation which does not require a period of cosmological inflation is discussed. The School consisted of level-up courses intended for PhD students, as well as updating courses for postdocs and researchers. In addition, a few propaedeutical crash courses were organized to bridge the gaps in the attendance and to facilitate an active participation. The courses were held mostly on the blackboard. The audience was assumed to have at least a PhD student level either in phenomenological particle theory, in astroparticle physics or in field and string theory. One of the aims of the School was to bring together researchers of these different areas and to update them on one another's discipline. The School was divided in two workshops: Interface between Cosmology and Particle Physics Courses: W. GRIMUS and S. PETCOV: Neutrino Phenomenology A. MASIERO and F. FERUGLIO: Beyond the Standard Model P. ULLIO: Introduction to Dark Matter N. BILIC: Black holes phenomenology 2) Particle Physics, Gravity and String Theory Courses: R. BRANDENBERGER: Topics in Cosmology J. ZANELLI: Black holes physics C. NUNEZ: StringsGauge Correspondence A. JEVICKI: AdS/CFT G. DALL'AGATA: String vacua and moduli stabilization C. BURGESS: Cosmology and Strings G. CARDOSO: Black Holes and String Theory Seminars were held during the School: Seminars: D. DENEGRI: New physics at LHC D. WARK: Neutrino Experiments C. BACCIGALUPI: Review on Cosmological Experiments A. MUELLER: Experimental evidence of Black Holes S. LIBERATI: Astrophysical constraints on Lorentz violation In addition the following introductory courses were given during the first week: Introductory courses: M. BERTOLINI: Propaedeutical course in supersymmetry T. PROKOPEC: Propaedeutical course in cosmology G. BONELLI: Propaedeutical course of string theory M. SERONE: Propaedeutical course on physics of extra dimensions
Bohmian Particle Trajectories in Relativistic Fermionic Quantum Field Theory
Hrvoje Nikolic
2005-01-01
No Heading The de Broglie-Bohm interpretation of quantum mechanics and quantum field theory is generalized in such a way that it describes trajectories of relativistic fermionic particles and antiparticles and provides a causal description of the processes of their creation and destruction. A general method of causal interpretation of quantum systems is developed and applied to a causal interpretation of
Wechsler, Risa H.
9/16/2009 Andy Haas Stanford Student Orientation: Accelerator based Particle Physics 1 Accelerator, 2009 #12;9/16/2009 Andy Haas Stanford Student Orientation: Accelerator based Particle Physics 2 Stanford Student Orientation: Accelerator based Particle Physics 5 Super B (to be built near Frascati lab
Research program in particle physics. Progress report, January 1, 1993--December 1993
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.
Toward a physical theory of quantum cognition.
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
Master Equation for a Quantum Particle in a Gas
Hornberger, Klaus [Arnold Sommerfeld Center for Theoretical Physics, Ludwig-Maximilians-Universitaet Muenchen, Theresienstrasse 37, 80333 Munich (Germany)
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.
Motivating quantum field theory: the boosted particle in a box
Amar C. Vutha
2013-02-05
It is a maxim often stated, yet rarely illustrated, that the combination of special relativity and quantum mechanics necessarily leads to quantum field theory. An elementary illustration is provided, using the familiar particle in a box, boosted to relativistic speeds. It is shown that quantum fluctuations of momentum lead to energy fluctuations, that are inexplicable without a framework that endows the vacuum with dynamical degrees of freedom and allows particle creation/annihilation.
On Universal Physical Reality in the Light of Quantum Consciousness
Pabitra Pal Choudhury; Swapan Kumar Dutta; Sk. Sarif Hassan; Sudhakar Sahoo
2009-07-08
In this paper, we have first given an intuitive definition of "Consciousness" as realized by us. Next, from this intuitive definition we derived the physical definition of quantum consciousness (Quantum Consciousness Parameter or QCP). This QCP is the elementary level of consciousness in quantum particles, which are the most elementary particles in nature. Thus QCP can explain both the perceptible and non-perceptible nature and some existing postulates of physics. We conceptualize that the level of human consciousness is most complex having highest fractal dimension of 4.85 in the electroencephalographs experiment done by other research groups. On the other hand, other species are having lesser consciousness level, which can be reflected by lesser fractal dimensions. We have also explored the bio informatics of consciousness from genome viewpoints where we tried to draw an analogy of neurons with electrons and photons. Lastly, we refine the quantum mechanics in terms of QCP; we all know that in Einstein's special theory of relativity, Einstein has used the postulate "Consistency of the velocity of light irrespective of all frames of reference (inertial or non-inertial frames)". In our theoretical revelation QCP can be directly applied to get a confirmatory proof of this postulate. Thus the postulate can be framed as a law.
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.
(Medium energy particle physics): Annual progress report
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.
Development of quantum perspectives in modern physics
NASA Astrophysics Data System (ADS)
Baily, Charles; Finkelstein, Noah D.
2009-06-01
Introductory undergraduate courses in classical physics stress a perspective that can be characterized as realist; from this perspective, all physical properties of a classical system can be simultaneously specified and thus determined at all future times. Such a perspective can be problematic for introductory quantum physics students, who must develop new perspectives in order to properly interpret what it means to have knowledge of quantum systems. We document this evolution in student thinking in part through pre- and post-instruction evaluations using the Colorado Learning Attitudes about Science Survey. We further characterize variations in student epistemic and ontological commitments by examining responses to two essay questions, coupled with responses to supplemental quantum attitude statements. We find that, after instruction in modern physics, many students are still exhibiting a realist perspective in contexts where a quantum-mechanical perspective is needed. We further find that this effect can be significantly influenced by instruction, where we observe variations for courses with differing learning goals. We also note that students generally do not employ either a realist or a quantum perspective in a consistent manner.
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.
On the Quantum-Classical Character of the Quantum Wavefunction of Material Particles
Daniela Dragoman
2006-04-12
We show that the quantum wavefunction, interpreted as the probability density of finding a single non-localized quantum particle, which evolves according to classical laws of motion, is an intermediate description of a material quantum particle between the quantum and classical realms. Accordingly, classical and quantum mechanics should not be treated separately, a unified description in terms of the Wigner distribution function being possible. Although defined on classical phase space coordinates, the Wigner distribution function accommodates the nonlocalization property of quantum systems, and leads to both the Schrodinger equation for the quantum wavefunction and to the definition of position and momentum operators.
Bringing Bell's theorem back to the domain of Particle Physics & Cosmology
Hiesmayr, Beatrix C
2015-01-01
John St. Bell was a physicist working most of his time at CERN and contributing intensively and sustainably to the development of Particle Physics and Collider Physics. As a hobby he worked on so-called "foundations of quantum theory", that was that time very unpopular, even considered to be scientifically taboo. His 1964-theorem, showing that predictions of local realistic theories are different to those of quantum theory, initiated a new field in quantum physics: quantum information theory. The violation of Bell's theorem, for instance, is a necessary and sufficient criterion for generating a secure key for cryptography at two distant locations. This contribution shows how Bell's theorem can be brought to the realm of high energy physics and presents the first conclusive experimental feasible test for weakly decaying neutral mesons on the market. Strong experimental and theoretical limitations make a Bell test in weakly decaying systems such as mesons and hyperons very challenging, however, these systems sh...
Studies in theoretical high energy particle physics. [Dept. of Physics, Univ. of Illinois at Chicago
Aratyn, H.; Brekke, L.; Keung, Wai-Yee; Sukhatme, U.
1993-01-01
Theoretical work on the following topics is briefly summarized: symmetry structure of conformal affine Toda model and KP hierarchy; solitons in the affine Toda and conformal affine Toda models; classical r-matrices and Poisson bracket structures on infinite-dimensional groups; R-matrix formulation of KP hierarchies and their gauge equivalence; statistics of particles and solitons; charge quantization in the presence of an Alice string; knotting and linking of nonabelian flux; electric dipole moments; neutrino physics in gauge theories; CP violation in the high energy colliders; supersymmetric quantum mechanics; parton structure functions in nuclei; dual parton model. 38 refs.
Bohmian particle trajectories in relativistic fermionic quantum field theory
H. Nikolic
2004-09-07
The de Broglie-Bohm interpretation of quantum mechanics and quantum field theory is generalized in such a way that it describes trajectories of relativistic fermionic particles and antiparticles and provides a causal description of the processes of their creation and destruction. A general method of causal interpretation of quantum systems is developed and applied to a causal interpretation of fermionic quantum field theory represented by c-number valued wave functionals.
Experimental particle physics. [Dept. of Physics, Drexel Univ
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.
Reflection of a Particle from a Quantum Measurement
Jonathan B. Mackrory; Kurt Jacobs; Daniel A. Steck
2010-09-25
We present a generalization of continuous position measurements that accounts for a spatially inhomogeneous measurement strength. This describes many real measurement scenarios, in which the rate at which information is extracted about position has itself a spatial profile, and includes measurements that detect if a particle has crossed from one region into another. We show that such measurements can be described, in their averaged behavior, as stochastically fluctuating potentials of vanishing time average. Reasonable constraints restrict the form of the measurement to have degenerate outcomes, which tend to drive the system to spatial superposition states. We present the results of quantum-trajectory simulations for measurements with a step-function profile (a "which-way" measurement) and a Gaussian profile. We find that the particle can coherently reflect from the measurement region in both cases, despite the stochastic nature of the measurement back-action. In addition, we explore the connection to the quantum Zeno effect, where we find that the reflection probability tends to unity as the measurement strength increases. Finally, we discuss two physical realizations of a spatially varying position measurement using atoms.
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.
Physical Interpretations of Nilpotent Quantum Mechanics
Rowlands, Peter
2010-01-01
Nilpotent quantum mechanics provides a powerful method of making efficient calculations. More importantly, however, it provides insights into a number of fundamental physical problems through its use of a dual vector space and its explicit construction of vacuum. Physical interpretation of the nilpotent formalism is discussed with respect to boson and baryon structures, the mass-gap problem, zitterbewgung, Berry phase, renormalization, and related issues.
Physical Interpretations of Nilpotent Quantum Mechanics
Peter Rowlands
2010-04-09
Nilpotent quantum mechanics provides a powerful method of making efficient calculations. More importantly, however, it provides insights into a number of fundamental physical problems through its use of a dual vector space and its explicit construction of vacuum. Physical interpretation of the nilpotent formalism is discussed with respect to boson and baryon structures, the mass-gap problem, zitterbewgung, Berry phase, renormalization, and related issues.
Quantum-behaved particle swarm optimization algorithm for economic load dispatch of power system
Zhisheng Zhang
2010-01-01
Quantum-behaved particle swarm optimization algorithm is firstly used in economic load dispatch of power system in this paper. Quantum-behaved particle swarm optimization algorithm is the integration of particle swarm optimization algorithm and quantum computing theory. The superposition characteristic and probability representation of quantum methodology are combined into particle swarm optimization algorithm. This can make a single particle be expressed by
Quantum Field Theory in Condensed Matter Physics
Alexei M. Tsvelik
2003-01-01
This course in modern quantum field theory for condensed matter physics includes a derivation of the path integral representation, Feynman diagrams and elements of the theory of metals. Alexei Tsvelik also covers Landau Fermi liquid theory and gradually turns to more advanced methods used in the theory of strongly correlated systems. The book contains a thorough exposition of such non-perturbative
Accelerators | Photon Science | Particle Physics Deutsches Elektronen-Synchrotron
Accelerators | Photon Science | Particle Physics Deutsches Elektronen-Synchrotron A Research Centre/m) Accelerator Research DESY DESY is one of the world's leading research centres for photon science, particle science, particle physics and atto-second science. The position of a senior scientist in accelerator
Accelerators | Photon Science | Particle Physics Deutsches Elektronen-Synchrotron
Accelerators | Photon Science | Particle Physics Deutsches Elektronen-Synchrotron A Research Centre science, particle physics and atto-second science. The position of a tenure track scientist in accelerator and XFEL · Study realistic applications of new accelerator technologies for photon science and particle
Entanglement of indistinguishable particles in condensed-matter physics
Mark R. Dowling; Andrew C. Doherty; Howard M. Wiseman
2006-01-01
The concept of entanglement in systems where the particles are indistinguishable has been the subject of much recent interest and controversy. In this paper we study the notion of entanglement of particles introduced by Wiseman and Vaccaro [Phys. Rev. Lett. 91, 097902 (2003)] in several specific physical systems, including some that occur in condensed-matter physics. The entanglement of particles is
C. M. Chandrashekar
2006-10-28
In most widely discussed discrete time quantum walk model, after every unitary shift operator, the particle evolves into the superposition of position space and settles down in one of its basis states, loosing entanglement in the coin space in the new position. The Hadamard operation is applied to let the particle to evolve into the superposition in the coin space and the walk is iterated. We present a model with a additional degree of freedom for the unitary shift operator $U^{\\prime}$. The unitary operator with additional degree of freedom will evolve the quantum particle into superposition of position space retaining the entanglement in coin space. This eliminates the need for quantum coin toss (Hadamard operation) after every unitary displacement operation as used in most widely studied version of the discrete time quantum walk model. This construction is easily extended to a multiple particle quantum walk and in this article we extend it for a pair of particles in pure state entangled in coin degree of freedom by simultaneously subjecting it to a pair of unitary displacement operators which were constructed for single particle. We point out that unlike for single particle quantum walk, upon measurement of its position after $N$ steps, the entangled particles are found together with 1/2 probability and at different positions with 1/2 probability. This can act as an advantage in applications of the quantum walk. A special case is also treated using a complex physical system such as, inter species two-particle entangled Bose-Einstein condensate, as an example.
8.05 Quantum Physics II, Fall 2002
Rajagopal, Krishna, 1965-
Together 8.05 and 8.06 cover quantum physics with applications drawn from modern physics. General formalism of quantum mechanics: states, operators, Dirac notation, representations, measurement theory. Harmonic oscillator: ...
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?
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'' (Paris-Sud University/Air Liquide).
Quantum gravity corrections to the tunneling radiation of scalar particles
Peng Wang; Haitang Yang; Shuxuan Ying
2014-10-19
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 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.
Multi-particle Correlations in Quaternionic Quantum Systems
S. P. Brumby; G. C. Joshi; Ronald Anderson
1994-06-09
We investigate the outcomes of measurements on correlated, few-body quantum systems described by a quaternionic quantum mechanics that allows for regions of quaternionic curvature. We find that a multi-particle interferometry experiment using a correlated system of four nonrelativistic, spin-half particles has the potential to detect the presence of quaternionic curvature. Two-body systems, however, are shown to give predictions identical to those of standard quantum mechanics when relative angles are used in the construction of the operators corresponding to measurements of particle spin components.
Multi-particle correlations in quaternionic quantum systems
Brumby, S P; Anderson, R
1994-01-01
We investigate the outcomes of measurements on correlated, few-body quantum systems described by a quaternionic quantum mechanics that allows for regions of quaternionic curvature. We find that a multi-particle interferometry experiment using a correlated system of four nonrelativistic, spin-half particles has the potential to detect the presence of quaternionic curvature. Two-body systems, however, are shown to give predictions identical to those of standard quantum mechanics when relative angles are used in the construction of the operators corresponding to measurements of particle spin components.
Interference of identical particles and the quantum work distribution.
Gong, Zongping; Deffner, Sebastian; Quan, H T
2014-12-01
Quantum-mechanical particles in a confining potential interfere with each other while undergoing thermodynamic processes far from thermal equilibrium. By evaluating the corresponding transition probabilities between many-particle eigenstates we obtain the quantum work distribution function for identical bosons and fermions, which we compare with the case of distinguishable particles. We find that the quantum work distributions for bosons and fermions significantly differ at low temperatures, while, as expected, at high temperatures the work distributions converge to the classical expression. These findings are illustrated with two analytically solvable examples, namely the time-dependent infinite square well and the parametric harmonic oscillator. PMID:25615058
Research accomplishments and future goals in particle physics
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.
Accelerators | Photon Science | Particle Physics Deutsches Elektronen-Synchrotron
Accelerators | Photon Science | Particle Physics Deutsches Elektronen-Synchrotron A Research CentreD-Students (f/m) DESY DESY is one of the world's leading research centres for photon science, particle and astroparticle physics as well as accelerator physics. The Photo Injector Test Facility PITZ in Zeuthen (near
Primer on Detectors and Electronics for Particle Physics Experiments
California at Santa Cruz, University of
1 Primer on Detectors and Electronics for Particle Physics Experiments Alexander A. Grillo Santa physics experiments. The intended readers are students, especially undergraduates, starting to work in our the primer itself. I Background of Particle Physics Scattering Experiments Physicists have made the most
Postdoctoral Position in Theoretical Nuclear and Elementary Particle Physics
Washington at Seattle, University of - Department of Physics, Electroweak Interaction Research Group
Postdoctoral Position in Theoretical Nuclear and Elementary Particle Physics Indiana University The Nuclear Theory group at the Physics Department of Indiana University invites ap- plications for a postdoctoral position in the fields of Nuclear Theory and Elementary Particle Physics, broadly defined
Synthesis and optical properties of quantum-size metal sulfide particles in aqueous solution
Nedeljkovic, J.M.; Patel, R.C.; Kaufman, P.; Joyce-Pruden, C.; O'Leary, N. (Clarkson Univ., Potsdam, NY (United States))
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.
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…
Particle physics confronts the solar neutrino problem
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.
Charting the Course for Elementary Particle Physics
Burton Richter
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.
Applied Physics Graduate Program The Rice Quantum Institute
Richards-Kortum, Rebecca
86 Applied Physics Graduate Program The Rice Quantum Institute Participating Faculty This programD Ajointeffortofboththenaturalsciencesandtheengineeringdivisionsat RiceandoverseenbytheRiceQuantumInstitute(RQI),theAppliedPhysics Program Mechanics I (PHYS 521 or CHEM 530) Quantum Mechanics II or Statistical Physics (PHYS 522 or PHYS 526 or CHEM
Strings as multi-particle states of quantum sigma-models
Nikolay Gromov; Vladimir Kazakov; Kazuhiro Sakai; Pedro Vieira
2007-01-01
We study the quantum Bethe ansatz equations in the O(2n) sigma-model for physical particles on a circle, with the interaction given by the Zamolodchikovs'S-matrix, in view of its application to quantization of the string on the S2n?1×Rt space. For a finite number of particles, the system looks like an inhomogeneous integrable O(2n) spin chain. Similarly to OSp(2m+n|2m) conformal sigma-model considered
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…
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.
Trace functions with applications in quantum physics
Frank Hansen
2013-07-02
We consider both known and not previously studied trace functions with applications in quantum physics. By using perspectives we obtain convexity statements for different notions of residual entropy, including the entropy gain of a quantum channel as studied by Holevo and others. We give new and simplified proofs of the Carlen-Lieb theorems concerning concavity or convexity of certain trace functions by making use of the theory of operator monotone functions. We then apply these methods in a study of new types of trace functions. Keywords: Trace function, convexity, entropy gain, residual entropy, operator monotone function.
Particle Physics in a Season of Change
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: Explore, Search, Measure! The first phase of running at the LHC has brought us to two new lands - in proton-proton and lead-lead collisions - and we may well enter other new lands with each change of energy or increase of sensitivity. I believe that it will prove very rewarding to spend some time simply exploring each new landscape, without strong preconceptions, to learn what is there and, perhaps, to encounter interesting surprises. Directed searches, for which we have made extensive preparations, are of self-evident interest. Here the challenge will be to broaden the searches over time, so the searches are not too narrowly directed. Our very successful conception of particles and forces is highly idealized. We have a great opportunity to learn just how comprehensive is our network of understanding by making precise measurements and probing for weak spots, or finding more sweeping accord between theory and experiment.
Quantum kinetics of spinning neutral particles: General theory and Spin wave dispersion
NASA Astrophysics Data System (ADS)
Andreev, P. A.
2015-08-01
Plasma physics gives an example of physical system of particles with the long-range interaction. At the small velocities of particles we can consider the plasmas approximately as the systems of particles with the Coulomb interaction. The Coulomb interaction is an isotropic interaction. Systems of spinning neutral particles are involved in the spin-spin interaction, which is a long-range anisotropic interparticle interaction. Therefore they can reveal more rich properties than the Coulomb plasmas. Furthermore, to study the systems of spinning particles we can develop the kinetic and hydrodynamic methods similar to the methods applying in the plasma physics. We derive the kinetic equations by a new method, which is the generalization of the many-particle quantum hydrodynamics. Obtained set of the kinetic equations is truncated, so we have a closed set of two equations. First of them is the kinetic equation for the quantum distribution function. The second equation is the equation for the spin-distribution function, which describes the spin kinetic evolution and contributes to the time evolution of the distribution function. Our method allows one to obtain equations for both the three dimensional systems of particles and the low dimensional systems. Hence we consider the spin waves in the three- and the two-dimensional systems of neutral spinning particles.
Particles, Waves, and the Interpretation of Quantum Mechanics
ERIC Educational Resources Information Center
Christoudouleas, N. D.
1975-01-01
Presents an explanation, without mathematical equations, of the basic principles of quantum mechanics. Includes wave-particle duality, the probability character of the wavefunction, and the uncertainty relations. (MLH)
Bohmian particle trajectories in relativistic bosonic quantum field theory
Hrvoje Nikolic
2002-01-01
We study the de Broglie-Bohm interpretation of bosonic relativistic quantum\\u000amechanics and argue that the negative densities and superluminal velocities\\u000athat appear in this interpretation do not lead to inconsistencies. After that,\\u000awe study particle trajectories in bosonic quantum field theory. A new\\u000acontinuously changing hidden variable - the effectivity of a particle (a number\\u000abetween 0 and 1) -
Charles Baily
2011-09-06
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.
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)
The straw man of quantum physics
Peter Morgan
2008-10-15
The violation of Bell inequalities by experiment has convinced physicists that we cannot maintain a classical view of the world. When we argue against the possibility of local realist hidden-variable models, however, the ubiquitous requirement of realism, that "measurement results depend on pre-existing properties of objects that are independent of the measurement", reduces classical theory to a straw man. When our most successful physical theories have been field theories for well over a century, and probabilistic for almost as long, the proper comparison is between quantum fields and random fields, for which there are no sharply defined objects and no properties, so that realism is inapplicable. If we model quantum fluctuations explicitly, we can construct random field models as alternatives to quantum field models.
Quantum Theory over a Galois Field and Applications to Gravity and Particle Theory
Felix M. Lev
2014-04-30
We argue that the main reason of crisis in quantum physics is that nature, which is fundamentally discrete, is described by continuous mathematics. Moreover, no ultimate physical theory can be based on continuous mathematics because, as follows from G\\"{o}del's incompleteness theorems, that mathematics is not self-consistent. In the first part of the work we discuss inconsistencies in standard approach to quantum theory and reformulate the theory such that it can be naturally generalized to a formulation based on discrete mathematics. It is shown that the cosmological acceleration and gravity can be treated simply as {\\it kinematical} manifestations of de Sitter symmetry on quantum level ({\\it i.e. for describing those phenomena the notions of dark energy, space-time background and gravitational interaction are not needed}). In the second part of the work we argue that fundamental quantum theory should be based on a Galois field with a large characteristic $p$. In this approach the de Sitter gravitational constant depends on $p$ and disappears in the formal limit $p\\to\\infty$, i.e. gravity is a consequence of finiteness of nature. The application of the approach to particle theory gives the following results: a) no neutral elementary particles can exist; b) the electric charge and the baryon and lepton quantum numbers can be only approximately conserved (i.e. the notion of a particle and its antiparticle is only approximate). We also consider a possibility that only Dirac singletons can be true elementary particles.
Atul Kumar; Mangala Sunder Krishnan
2007-10-18
Construction of multi-particle entangled states and direct teleportation of N-(spin 1/2) particles are important areas of quantum information processing. A number of different schemes which have been presented already, address the problem through controlled teleportation. In this article, a criterion based on standard quantum statistical correlations employed in the many body virial expansions is used to determine maximum entanglement for a N-particle state. These states remain entangled through proper traces to states for a smaller number of particles and can be generalized for arbitrary number of particles. It is shown that they are quite useful in generalized, N-particle, direct teleportation. The corresponding quantum gates are also indicated for teleportation schemes from simple computational basis states.
Optimizing entangling quantum gates for physical systems
Mueller, M. M.; Murphy, M.; Calarco, T. [Institut fuer Quanteninformationsverarbeitung, Universitaet Ulm, 89081 Ulm (Germany); Reich, D. M.; Koch, C. P. [Institut fuer Theoretische Physik, Freie Universitaet Berlin, Arnimallee 14, 14195 Berlin (Germany); Institut fuer Physik, Universitaet Kassel, Heinrich-Plett-Str. 40, 34132 Kassel (Germany); Yuan, H. [Research Laboratory of Electronics, Massachusetts Institute of Technology, Cambridge, MA 02139 (United States); Vala, J. [Department of Mathematical Physics, National University of Ireland, Maynooth (Ireland); School of Theoretical Physics, Dublin Institute for Advanced Studies, 10 Burlington Rd., Dublin (Ireland); Whaley, K. B. [Department of Chemistry, University of California, Berkeley, California 94720 (United States)
2011-10-15
Optimal control theory is a versatile tool that presents a route to significantly improving figures of merit for quantum information tasks. We combine it here with the geometric theory for local equivalence classes of two-qubit operations to derive an optimization algorithm that determines the best entangling two-qubit gate for a given physical setting. We demonstrate the power of this approach for trapped polar molecules and neutral atoms.
Quantum limited particle sensing in optical tweezers
Tay, J.W. [Jack Dodd Centre for Photonics and Ultracold Atoms, Department of Physics, University of Otago, Dunedin (New Zealand); Hsu, Magnus T. L. [School of Mathematics and Physics, University of Queensland, St. Lucia, Queensland 4072 (Australia); Bowen, Warwick P. [Jack Dodd Centre for Photonics and Ultracold Atoms, Department of Physics, University of Otago, Dunedin (New Zealand); School of Mathematics and Physics, University of Queensland, St. Lucia, Queensland 4072 (Australia)
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.
Covariant Quantum Green's Function for an Accelerated Particle
T. Garavaglia
2001-04-03
Covariant relativistic quantum theory is used to study the covariant Green's function, which can be used to determine the proper time evolved wave functions that are solutions to the covariant Schr\\"odinger type equation for a massive spin zero particle. The concept of covariant action is used to obtain the Green's function for an accelerated relativistic particle.
Bohmian particle trajectories in relativistic bosonic quantum field theory
H. Nikolic
2004-01-22
We study the de Broglie-Bohm interpretation of bosonic relativistic quantum mechanics and argue that the negative densities and superluminal velocities that appear in this interpretation do not lead to inconsistencies. After that, we study particle trajectories in bosonic quantum field theory. A new continuously changing hidden variable - the effectivity of a particle (a number between 0 and 1) - is postulated. This variable leads to a causal description of processes of particle creation and destruction. When the field enters one of nonoverlapping wave-functional packets with a definite number of particles, then the effectivity of the particles corresponding to this packet becomes equal to 1, while that of all other particles becomes equal to 0.
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.
Trajectory-based Theory of Relativistic Quantum Particles
Bill Poirier
2012-08-30
Recently, a self-contained trajectory-based formulation of non-relativistic quantum mechanics was developed [Ann. Phys. 315, 505 (2005); Chem. Phys. 370, 4 (2010); J. Chem. Phys. 136, 031102 (2012)], that makes no use of wavefunctions or complex amplitudes of any kind. Quantum states are represented as ensembles of real-valued quantum trajectories that extremize a suitable action. Here, the trajectory-based approach is developed into a viable, generally covariant, relativistic quantum theory for single (spin-zero, massive) particles. Central to this development is the introduction of a new notion of global simultaneity for accelerated particles--together with basic postulates concerning probability conservation and causality. The latter postulate is found to be violated by the Klein-Gordon equation, leading to its well-known problems as a single-particle theory. Various examples are considered, including the time evolution of a relativistic Gaussian wavepacket.
Quantum graphs with two-particle contact interactions
NASA Astrophysics Data System (ADS)
Bolte, Jens; Kerner, Joachim
2013-02-01
We construct models of many-particle quantum graphs with singular two-particle contact interactions, which can be either hardcore- or ?-interactions. Self-adjoint realizations of the two-particle Laplacian including such interactions are obtained via their associated quadratic forms. We prove discreteness of spectra as well as Weyl laws for the asymptotic eigenvalue counts. These constructions are first performed for two distinguishable particles and then for two identical bosons. Furthermore, we extend the models to N bosons with two-particle interactions, thus implementing the Lieb-Liniger model on a graph.
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.
Quantum kinetics of spinning neutral particles: General theory and Spin wave dispersion
P. A. Andreev
2013-08-16
Plasma physics give an example of physical system of particles with the long range interaction. At small velocity of particles we can consider the plasma approximately as a system of particles with the Coulomb interaction. The Coulomb interaction is isotropic. Systems of spinning neutral particles have long-range anisotropic interparticle interaction. So, they can reveal more reach properties than plasma. Furthermore for studying of systems of spinning particles we can develop kinetic and hydrodynamic methods analogous to used for the plasma. We derive kinetic equations by a new method, which is the generalization of the many-particle quantum hydrodynamics. Obtained set of kinetic equations is truncated, so we have closed set of two equations. One of them is the kinetic equation for quantum distribution function. The second equation is the equation for the spin-distribution. Which describes the spin kinetic evolution and gives contribution in time evolution of the distribution function. Our method allows to obtain equations as for three dimensional system of particles and for low dimensional systems. So, we consider spin waves in three- and two dimensional systems of neutral spinning particles.
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…
Applied Physics Graduate Program The Rice Quantum Institute
Richards-Kortum, Rebecca
Applied Physics Graduate Program The Rice Quantum Institute Participating Faculty I (PHYS 521 or CHEM 530) Quantum Mechanics II or Statistical Physics (PHYS 522 or PHYS 526 or CHEM the natural sciences and the engineering divisions at Rice and overseen by the Rice Quantum Institute (RQI
Foundations of quantum physics: a general realistic and operational approach
Aerts, Diederik
Foundations of quantum physics: a general realistic and operational approach Diederik Aerts FUND of quantum physics: a general realistic and operational approach", International Journal of Theoretical examples in detail in the light of this formalism: a classical deterministic entity and a quantum entity
Harvard University Physics 143b: Quantum Mechanics II
Harvard University Physics 143b: Quantum Mechanics II Instructor : Subir Sachdev, Lyman 343@physics.harvard.edu This is the second half of an introductory course on quantum mechanics. The course will complete the text book: the photon 5. Relativistic quantum mechanics: the Dirac equation 6. Scattering theory. 7. Einstein
Bao, Lei
Understanding probabilistic interpretations of physical systems: A prerequisite to learning quantum Association of Physics Teachers. DOI: 10.1119/1.1447541 I. INTRODUCTION A student's first course in quantum the difficulties students have in learning quantum physics. The purpose of this paper is to discuss the highlights
Highlights INFM 2000/2001 1.Atomic and Molecular Physics, Quantum Electronics and Plasma Physics
D'Ariano, Giacomo Mauro
Highlights INFM 2000/2001 1.Atomic and Molecular Physics, Quantum Electronics and Plasma Physics 1, processing, storing, or computing. The marriage of Quantum Physics and Information Technology -originally.2 EXPERIMENTAL CHARACTERIZATION OF THE TRANSFER MATRIX OF A QUANTUM DEVICE It is unquestionable that the current
Entanglement of indistinguishable particles in condensed matter physics
Mark R. Dowling; Andrew C. Doherty; Howard M. Wiseman
2006-10-13
The concept of entanglement in systems where the particles are indistinguishable has been the subject of much recent interest and controversy. In this paper we study the notion of entanglement of particles introduced by Wiseman and Vaccaro [Phys. Rev. Lett. 91, 097902 (2003)] in several specific physical systems, including some that occur in condensed matter physics. The entanglement of particles is relevant when the identical particles are itinerant and so not distinguished by their position as in spin models. We show that entanglement of particles can behave differently to other approaches that have been used previously, such as entanglement of modes (occupation-number entanglement) and the entanglement in the two-spin reduced density matrix. We argue that the entanglement of particles is what could actually be measured in most experimental scenarios and thus its physical significance is clear. This suggests entanglement of particles may be useful in connecting theoretical and experimental studies of entanglement in condensed matter systems.
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.
Quantum Delayed-Choice Experiment and Wave-Particle Superposition
NASA Astrophysics Data System (ADS)
Guo, Qi; Cheng, Liu-Yong; Wang, Hong-Fu; Zhang, Shou
2014-12-01
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.
Physical properties of sewage particles in seawater
Elaine K. Baker; Peter T. Harris; Brett Kensett-Smith; David F. Bagster; Dennis M. Nobbs
1995-01-01
Samples of primary-treated effluent were examined by laser particle sizer, photographic image-analysis and in settling\\/rinsing experiments in order to determine particle sizes and falling\\/rising speeds through sea-water. Using a 1.7 m column and 24 h experiments, it was found that approximately 22% of the particles settle out of suspension, 3% rise to the surface and 75% remain in suspension. Between
Physics of particles in the rotating tube
Miroslav Pardy
2011-09-08
The classical and the quantum motion of a massive body in the rotating tube is considered. Photon is included. The spin motion described by the Bargmann-Michel-Telegdi equation is considered in the rotation tube and rotating system.
Applied Physics Graduate Program The Rice Quantum Institute
Richards-Kortum, Rebecca
1 Applied Physics Graduate Program The Rice Quantum Institute Participating Faculty This program and the engineering divisions at Rice and overseen by the Rice Quantum Institute (RQI), the Applied Physics Program is open to faculty from physics and astronomy, chemistry, mechanical engineering and materials science
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…
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…
Accelerators | Photon Science | Particle Physics Deutsches Elektronen-Synchrotron
physics as well as accelerator physics. DESY's optical laser group is responsible for research in high-power, high-repetition rate or fiber laser development be- neficial · Basic knowledgeAccelerators | Photon Science | Particle Physics Deutsches Elektronen-Synchrotron A Research Centre
A quantum solution to Gibbs paradox with few particles
NASA Astrophysics Data System (ADS)
Dong, Hui; Cai, ChengYun; Sun, ChangPu
2012-10-01
We present a fully quantum solution to the Gibbs paradox (GP) with an illustration based on a gedanken experiment with two particles trapped in an infinite potential well. The well is divided into two cells by a solid wall, which could be removed for mixing the particles. For the initial thermal state with correct two-particle wavefunction according to their quantum statistics, the exact calculations show the entropy changes are the same for boson, fermion and non-identical particles. With the observation that the initial unmixed state of identical particles in the conventional presentations actually is not of a thermal equilibrium, our analysis reveals the quantum origin of the paradox, and confirms Jaynes' observation that entropy increase in Gibbs mixing is only due to the including more observables. To further show up the subtle role of the quantum mechanism in the GP, we study the different finite size effect on the entropy change and show the work performed in the mixing process is different for various types of particles.
Group action in topos quantum physics
Flori, C. [Perimeter Institute for Theoretical Physics, 31 Caroline Street N, Waterloo, Ontario N2L 2Y5 (Canada)] [Perimeter Institute for Theoretical Physics, 31 Caroline Street N, Waterloo, Ontario N2L 2Y5 (Canada)
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.
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.
On the Physical Hilbert Space of Loop Quantum Cosmology
Karim Noui; Alejandro Perez; Kevin Vandersloot
2004-11-09
In this paper we present a model of Riemannian loop quantum cosmology with a self-adjoint quantum scalar constraint. The physical Hilbert space is constructed using refined algebraic quantization. When matter is included in the form of a cosmological constant, the model is exactly solvable and we show explicitly that the physical Hilbert space is separable consisting of a single physical state. We extend the model to the Lorentzian sector and discuss important implications for standard loop quantum cosmology.
Concrete Foundations for Categorical Quantum Physics
Lehmann, Daniel
2010-01-01
An original presentation of Categorical Quantum Physics, in the line of Abramsky and Coecke, tries to introduce only objects and assumptions that are clearly relevant to Physics and does not assume compact closure. Adjoint arrows, tensor products and biproducts are the ingredients of this presentation. Tensor products are defined, up to a unitary arrow, by a universal property related to transformations of composite systems, not by assuming a monoidal structure. Entangled states of a tensor product define mixed states on the components of the tensor product. Coproducts that fit the adjoint structure are shown to be defined up to a unitary arrow and to provide biproducts. An abstract no-cloning result is proved.
Concrete Foundations for Categorical Quantum Physics
Daniel Lehmann
2010-12-29
An original presentation of Categorical Quantum Physics, in the line of Abramsky and Coecke, tries to introduce only objects and assumptions that are clearly relevant to Physics and does not assume compact closure. Adjoint arrows, tensor products and biproducts are the ingredients of this presentation. Tensor products are defined, up to a unitary arrow, by a universal property related to transformations of composite systems, not by assuming a monoidal structure. Entangled states of a tensor product define mixed states on the components of the tensor product. Coproducts that fit the adjoint structure are shown to be defined up to a unitary arrow and to provide biproducts. An abstract no-cloning result is proved.
Quantum interference of particles and resonances
Ya. Azimov
2010-02-09
Though the phenomenon of quantum-mechanical interference has been known for many years, it still has many open questions. The present review discusses specifically how the interference of resonances may and does work. We collect data on the search for rare decay modes of well-known resonances that demonstrate a wide variety of possible different manifestations of interference. Some special kinds of resonance interference, not yet sufficiently studied and understood, are also briefly considered. The interference may give useful experimental procedures to search for new resonances with arbitrary quantum numbers, even with exotic ones, and to investigate their properties.
Many-particle quantum graphs and Bose-Einstein condensation
NASA Astrophysics Data System (ADS)
Bolte, Jens; Kerner, Joachim
2014-06-01
In this paper, we propose quantum graphs as one-dimensional models with a complex topology to study Bose-Einstein condensation and phase transitions in a rigorous way. We first investigate non-interacting many-particle systems on quantum graphs and provide a complete classification of systems that exhibit Bose-Einstein condensation. We then consider models of interacting particles that can be regarded as a generalisation of the well-known Tonks-Girardeau gas. Here, our principal result is that no phase transitions occur in bosonic systems with repulsive hardcore interactions, indicating an absence of Bose-Einstein condensation.
Quantum interference effects in particle transport through square lattices.
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
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.
MEASUREMENTS OF BLACK CARBON PARTICLES CHEMICAL, PHYSICAL, AND OPTICAL PROPERTIES
Onasch, T.B.; Sedlacek, A.; Cross, E. S.; Davidovits, P.; Worsnop, D. R.; Ahern, A.; Lack, D. A.; Cappa, C. D.; Trimborn, A.; Freedman, A.; Olfert, J. S.; Jayne, J. T.; Massoli, P.; Williams, L. R.; Mazzoleni, C.; Schwarz, J. P.; Thornhill, D. A.; Slowik, J. G.; Kok, G. L.; Brem, B. T.; Subramanian, R.; Spackman, J. R.; Freitag, S.; and Dubey, M. K.
2009-12-14
Accurate measurements of the chemical, physical, and optical properties of aerosol particles containing black carbon are necessary to improve current estimates of the radiative forcing in the atmosphere. A collaborative research effort between Aerodyne Research, Inc. and Boston College has focused on conducting field and laboratory experiments on carbonaceous particles and the development and characterization of new particulate instrumentation. This presentation will focus on the chemical, physical, and optical properties of black carbon particles measured in the laboratory in order to understand the effects of atmospheric processing on black carbon particles. Results from a three-week study during July 2008 of mass- and optical-based black carbon measurements will be presented. The project utilized the Boston College laboratory flame apparatus and aerosol conditioning and characterization equipment. A pre-mixed flat flame burner operating at controlled fuel-to-air ratios produced stable and reproducible concentrations of soot particles with known sizes, morphologies, and chemical compositions. In addition, other black carbon particle types, including fullerene soot, glassy carbon spheres, oxidized flame soot, Regal black, and Aquadag, were also atomized, size selected, and sampled. The study covered an experimental matrix that systematically selected particle mobility size (30 to 300 nm) and black carbon particle mass, particle number concentration, particle shape (dynamic shape factor and fractal dimension), and particle chemistry and density (changed via coatings). Particles were coated with a measured thickness (few nm to {approx}150 nm) of sulfuric acid or bis (2-ethylhexyl) sebacate and passed through a thermal denuder to remove the coatings. Highlights of the study to be presented include: (1) Characterization of the chemical and physical properties of various types of black carbon particles, (2) Mass specific absorption measurements as a function of fuel-to-air ratio and carbon particle type, (3) Optical absorption nhancement measurements as a function of coatings, and (4) Particle shape determination as a function of fuel-to-air ratio and collapse observed due to coatings.
Interactions.org: Particle Physics News and Resources
NSDL National Science Digital Library
The Interactions.org website serves as a hub for news, information, images, and links for particle physicists. Educators and students can find a sizeable image collection and short videos and animations describing the research and history of key physics institutions. Researchers can discover a global data grid and a database of talks in cosmic physics, linear collider, ethics and science, and other particle physics topics. The website offers links to various physics glossaries, universities, and societies. Individuals can learn about education and funding opportunities.
Bringing Bell's theorem back to the domain of Particle Physics & Cosmology
Beatrix C. Hiesmayr
2015-02-13
John St. Bell was a physicist working most of his time at CERN and contributing intensively and sustainably to the development of Particle Physics and Collider Physics. As a hobby he worked on so-called "foundations of quantum theory", that was that time very unpopular, even considered to be scientifically taboo. His 1964-theorem, showing that predictions of local realistic theories are different to those of quantum theory, initiated a new field in quantum physics: quantum information theory. The violation of Bell's theorem, for instance, is a necessary and sufficient criterion for generating a secure key for cryptography at two distant locations. This contribution shows how Bell's theorem can be brought to the realm of high energy physics and presents the first conclusive experimental feasible test for weakly decaying neutral mesons on the market. Strong experimental and theoretical limitations make a Bell test in weakly decaying systems such as mesons and hyperons very challenging, however, these systems show an unexpected and puzzling relation to another big open question: why is our Universe dominated by matter, why did the antimatter slip off the map? This long outstanding problem becomes a new perspective via the very idea behind quantum information.
Relativistic Quantum Physics at Your Pencil Tips: Dirac Fermion in Graphitic Carbon
Philip Kim
2007-01-01
The massless Dirac particle moving at the speed of light has been a fascinating subject in relativistic quantum physics. Graphene, an isolated single atomic layer of graphite, now provides us an opportunity to investigate such exotic effect in low-energy condensed matter systems. The unique electronic band structure of graphene lattice provides a linear dispersion relation where the Fermi velocity replaces
Quantum Field Theories on a Noncommutative Euclidean Space: Overview of New Physics
Yong-Shi Wu
2003-06-05
In this talk I briefly review recent developments in quantum field theories on a noncommutative Euclidean space, with Heisenberg-like commutation relations between coordinates. I will be concentrated on new physics learned from this simplest class of non-local field theories, which has applications to both string theory and condensed matter systems, and possibly to particle phenomenology.
Unified statistical distribution of quantum particles and Symmetry
Ahmad Adel Abutaleb
2014-06-10
In this paper we propose a unified statistics of Bose-Einstein and Fermi-Dirac statistics by suggesting that every particle can be associated with matter or fundamental forces with certain probability. The main Justification for this proposal is the possibility of extension of the spin-statistics theory to include a hypothesis quantum particles have fractional spin. The concept of Supersymmetry can be related to this unified statistics.
Quantum-Behaved Particle Swarm Optimization Algorithm with Controlled Diversity
Jun Sun; Wenbo Xu; Wei Fang
2006-01-01
\\u000a Premature convergence, the major problem that confronts evolutionary algorithms, is also encountered with the Particle Swarm\\u000a Optimization (PSO) algorithm. In the previous work [11], [12], [13], the Quantum-behaved Particle Swarm (QPSO) is proposed.\\u000a This novel algorithm is a global-convergence-guaranteed and has a better search ability than the original PSO. But like other\\u000a evolutionary optimization technique, premature in the QPSO is
Cognitive Mapping of Advanced Level Physics Students' Conceptions of Quantum Physics.
ERIC Educational Resources Information Center
Mashhadi, Azam; Woolnough, Brian
This paper presents findings from a study that investigated students' understanding of quantum phenomena and focused on how students incorporate the ideas of quantum physics into their overall cognitive framework. The heuristic metaphor of the map is used to construct graphic representations of students' understanding of quantum physics. The…
Quarks and Leptones: An Introductory Course in Modern Particle Physics
Francis Halzen; Alan D. Martin
1984-01-01
This self-contained text describes breakthroughs in our understanding of the structure and interactions of elementary particles. It provides students of theoretical or experimental physics with the background material to grasp the significance of these developments.
Astro particle physics with AMS on the International Space Station
R. Battiston
2003-01-01
We review how AMS will study open issues on astro particle physics operating for three years on the International Space Station, complementary to searches done at underground and accelerator facilities.
Strictly contractive quantum channels and physically realizable quantum computers Maxim Raginsky*
Raginsky, Maxim
Strictly contractive quantum channels and physically realizable quantum computers Maxim Raginsky study the robustness of quantum computers under the influence of errors modeled by strictly contractive channels render the states of the computer less distinguishable in the sense of quantum detection theory
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.
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.
Lindblad- and non-Lindblad-type dynamics of a quantum Brownian particle
Maniscalco, S. [School of Pure and Applied Physics, University of KwaZulu-Natal, Durban 4041 (South Africa); INFM, MIUR and Dipartimento di Scienze Fisiche ed Astronomiche dell'Universita di Palermo, via Archirafi 36, 90123 Palermo (Italy); Piilo, J. [School of Pure and Applied Physics, University of KwaZulu-Natal, Durban 4041 (South Africa); Department of Physics, University of Turku, FIN-20014 Turun yliopisto (Finland); Helsinki Institute of Physics, PL 64, FIN-00014 Helsingin yliopisto (Finland); Intravaia, F. [Laboratoire Kastler Brossel, Ecole Normale Superieure, Centre National de la Recherche Scientifique, Universite Pierre et Marie Curie, Case 74, 4 place Jussieu, F-75252 Paris (France); Petruccione, F. [School of Pure and Applied Physics, University of KwaZulu-Natal, Durban 4041 (South Africa); Messina, A. [INFM, MIUR and Dipartimento di Scienze Fisiche ed Astronomiche dell'Universita di Palermo, via Archirafi 36, 90123 Palermo (Italy)
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.
Localised particles and fuzzy horizons: A tool for probing Quantum Black Holes
Casadio, R
2013-01-01
The horizon is a classical concept that arises in general relativity, and is therefore not clearly defined when the source cannot be reliably described by classical physics. To any (sufficiently) localised quantum mechanical wave-function, one can associate a horizon wave-function which yields the probability of finding a horizon of given radius centred around the source. We can then associate to each quantum particle a probability that it is a black hole, and the existence of a minimum black hole mass follows naturally, which agrees with the one obtained from the hoop conjecture and the Heisenberg uncertainty principle.
Localised particles and fuzzy horizons: A tool for probing Quantum Black Holes
R. Casadio
2013-05-14
The horizon is a classical concept that arises in general relativity, and is therefore not clearly defined when the source cannot be reliably described by classical physics. To any (sufficiently) localised quantum mechanical wave-function, one can associate a horizon wave-function which yields the probability of finding a horizon of given radius centred around the source. We can then associate to each quantum particle a probability that it is a black hole, and the existence of a minimum black hole mass follows naturally, which agrees with the one obtained from the hoop conjecture and the Heisenberg uncertainty principle.
Photonic dark matter portal and quantum physics
S. A. Alavi; F. S. Kazemian
2015-06-14
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. We also calculate the contribution from the hidden photonic portal to the anomalous magnetic moment of the muon, which provides an important probe of physics beyond the standard model.
Energetic particle physics with applications in fusion and space plasmas
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.
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…
Particle Physics: Hot Topics Recreating the Big Bang
Particle Physics: Hot Topics Recreating the Big Bang The Large Hadron Collider will allow the beginning of time (the Big Bang). By colliding beams of energetic particles and studying the debris about 14 billion years ago in the Big Bang. This was an `explosion' of energy and matter, particularly
Entanglement of indistinguishable particles in condensed-matter physics
Mark R. Dowling; Andrew C. Doherty; Howard M. Wiseman
2006-01-01
The concept of entanglement in systems where the particles are\\u000aindistinguishable has been the subject of much recent interest and controversy.\\u000aIn this paper we study the notion of entanglement of particles introduced by\\u000aWiseman and Vaccaro [Phys. Rev. Lett. 91, 097902 (2003)] in several specific\\u000aphysical systems, including some that occur in condensed matter physics. The\\u000aentanglement of particles
No Labeling Quantum Mechanics of Indiscernible Particles
NASA Astrophysics Data System (ADS)
Domenech, G.; Holik, F.; Kniznik, L.; Krause, D.
2010-12-01
Our aim in this paper is to show an example of the formalism we have developed to avoid the label-tensor-product-vector-space-formalism of quantum mechanics when dealing with indistinguishable quanta. States in this new vector space, that we call the Q-space, refer only to occupation numbers and permutation operators act as the identity operator on them, reflecting in the formalism the unobservability of permutations, a goal of quasi-set theory.
ADVANCES IN IMAGING AND ELECTRON PHYSICS, VOL. 128 Quantum Tomography
D'Ariano, Giacomo Mauro
ADVANCES IN IMAGING AND ELECTRON PHYSICS, VOL. 128 Quantum Tomography G. MAURO D'ARIANO, MATTEO G. A. PARIS, and MASSIMILIANO F. SACCHI Quantum Optics and Information Group, Istituto Nazionale per la ............................. 223 B. Conventional Tomographic Imaging ...................... 224 1. Extension to the Quantum Domain
Harvard University Physics 143b: Quantum Mechanics II
Harvard University Physics 143b: Quantum Mechanics II Instructor : Subir Sachdev, Lyman 343@fas.harvard.edu This is the second half of an introductory course on quantum mechanics. The course will complete the text book: the photon 5. Relativistic quantum mechanics: the Dirac equation 6. Einstein-Podolsky-Rosen "paradox", Bell
Introduction to Quantum Algorithms for Physics and Chemistry
Man-Hong Yung; James D. Whitfield; Sergio Boixo; David G. Tempel; Alán Aspuru-Guzik
2012-03-06
In this introductory review, we focus on applications of quantum computation to problems of interest in physics and chemistry. We describe quantum simulation algorithms that have been developed for electronic-structure problems, thermal-state preparation, simulation of time dynamics, adiabatic quantum simulation, and density functional theory.
Gauge Theories & Particle Physics Physics 539 Spring Semester 1997 Chris *
Quigg, Chris
. Rees, "The Stanford Linear Collider," Sci. Am. 261, (October, 1989),* * p. 58. S. Myers and E for both orbital and radial excitations, construct a schemati* *c mass spectrum of (b~b) bound states a schemati* *c mass spectrum of ("b~"b) bound states. Label each state with its quantum numbers JPC
NASA Astrophysics Data System (ADS)
Wang, Bin
This thesis is composed of two parts. In the first part we summarize our study on implementation of quantum information processing (QIP) in optical cavity QED systems, while in the second part we present our numerical investigations on strongly interacting Fermi systems using a powerful numerical algorithm developed from the perspective of quantum information theory. We explore various possible applications of cavity QED in the strong coupling regime to quantum information processing tasks theoretically, including efficient preparation of Schrodinger-cat states for traveling photon pulses, robust implementation of conditional quantum gates on neutral atoms, as well as implementation of a hybrid controlled SWAP gate. We analyze the feasibility and performance of our schemes by solving corresponding physical models either numerically or analytically. We implement a novel numerical algorithm called Time Evolving Block Decimation (TEBD), which was proposed by Vidal from the perspective of quantum information science. With this algorithm, we numerically study the ground state properties of strongly interacting fermions in an anisotropic optical lattice across a wide Feshbach resonance. The interactions in this system can be described by a general Hubbard model with particle assisted tunneling. For systems with equal spin population, we find that the Luther-Emery phase, which has been known to exist only for attractive on-site interactions in the conventional Hubbard model, could also be found even in the case with repulsive on-site interactions in the general Hubbard model. Using the TEBD algorithm, we also study the effect of particle assisted tunneling in spin-polarized systems. Fermi systems with unequal spin population and attractive interaction could allow the existence of exotic superfluidity, such as the Fulde-Ferrell-Larkin-Ovchinnikov (FFLO) state. In the general Hubbard model, such exotic FFLO pairing of fermions could be suppressed by high particle assisted tunneling rates. However, at low particle assisted tunneling rates, the FFLO order could be enhanced. The effect of particle density inhomogeneity due to the presence of a harmonic trap potential is also discussed based on the local density approximation.
American particle and nuclear physics planning
Montgomery, Hugh E. [JLAB
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.
Elementary particle physics and high energy phenomena
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).
Quantum Heat Fluctuations of Single-Particle Sources
NASA Astrophysics Data System (ADS)
Battista, F.; Moskalets, M.; Albert, M.; Samuelsson, P.
2013-03-01
Optimal single electron sources emit regular streams of particles, displaying no low-frequency charge current noise. Because of the wave packet nature of the emitted particles, the energy is, however, fluctuating, giving rise to heat current noise. We investigate theoretically this quantum source of heat noise for an emitter coupled to an electronic probe in the hot-electron regime. The distribution of temperature and potential fluctuations induced in the probe is shown to provide direct information on the single-particle wave function properties and display strong nonclassical features.
Quantum Ground States as Equilibrium Particle-Vacuum Interaction States
Harold E. Puthoff
2012-03-08
A remarkable feature of atomic ground states is that they are observed to be radiationless in nature, despite (from a classical viewpoint) typically involving charged particles in accelerated motions. The simple hydrogen atom is a case in point. This universal groundstate characteristic is shown to derive from particle-vacuum interactions in which a dynamic equilibrium is established between radiation emission due to particle acceleration, and compensatory absorption from the zero-point fluctuations of the vacuum electromagnetic field. The result is a net radiationless ground state. This principle constitutes an overarching constraint that delineates an important feature of quantum ground states.
Quantum molecular dynamics and particle production in heavy ion collisions
S. W. Huang; A. Faessler; G. Q. Li; D. T. Khoa; E. Lehmann; M. A. Matin; N. Ohtsuka; R. K. Puri
1993-01-01
The production of photons, kaons, antikaons and antiprotons in heavy-ion collisions is calculated in the framework of ``quantum'' molecular dynamics (QMD). The Skyrme potentials, with parameters chosen to generate the soft and hard nuclear equations of state(EOS), are used in the propagation of nucleons within QMD. The sensitivity of the production of each type of particle to the EOS is
Colloquium: Majorana Fermions in nuclear, particle and solid-state physics
Elliott, S R
2014-01-01
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 anti-particle. 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 particles that may be truly neutral with no quantum number to distinguish them from their anti-particles. If such particles exist, they will influence many areas of nuclear and particle physics. Most notably the process of neutrinoless double beta decay can only exist if neutrinos are massive Majorana particles. Hence, many efforts to search for this proces...
FPGA-based Cherenkov Ring Recognition in Nuclear and Particle Physics Experiments
Jantsch, Axel
FPGA-based Cherenkov Ring Recognition in Nuclear and Particle Physics Experiments Ming Liu adopted to identify particles flying through the detector systems in nuclear and particle physics for particle recognition. 1 Introduction Nuclear and particle physics is a branch of physics that studies
Applied Physics Graduate Program The Rice Quantum Institute
Richards-Kortum, Rebecca
88 Applied Physics Graduate Program The Rice Quantum Institute Participating Faculty This program is open to faculty from physics and astronomy, chemistry, mechanical engineering and materials science of both the natural sciences and the engineering divisions at Rice and overseen by the Rice Quantum
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…
Pixel Detectors for Particle Physics and Imaging Applications
Wermes, N
2003-01-01
Semiconductor pixel detectors offer features for the detection of radiation which are interesting for particle physics detectors as well as for imaging e.g. in biomedical applications (radiography, autoradiography, protein crystallography) or in Xray astronomy. At the present time hybrid pixel detectors are technologically mastered to a large extent and large scale particle detectors are being built. Although the physical requirements are often quite different, imaging applications are emerging and interesting prototype results are available. Monolithic detectors, however, offer interesting features for both fields in future applications. The state of development of hybrid and monolithic pixel detectors, excluding CCDs, and their different suitability for particle detection and imaging, is reviewed.
The nilpotent Dirac equation and its applications in particle physics
Peter Rowlands
2003-01-01
The nilpotent Dirac formalism has been shown, in previous publications, to generate new physical explanations for aspects of particle physics, with the additional possibility of calculating some of the parameters involved in the Standard Model. The applications so far obtained are summarised, with an outline of some more recent developments.
The nilpotent Dirac equation and its applications in particle physics
Peter Rowlands
2003-01-15
The nilpotent Dirac formalism has been shown, in previous publications, to generate new physical explanations for aspects of particle physics, with the additional possibility of calculating some of the parameters involved in the Standard Model. The applications so far obtained are summarised, with an outline of some more recent developments.
Accelerators | Photon Science | Particle Physics Deutsches Elektronen-Synchrotron
, particle and astroparticle physics as well as accelerator physics. The Center for Free-Electron Laser) and its use in phase stabilized few-cycle pulse synthesizers, Free-Electron Lasers and Attosecond Science Â· Development of turn-key, burst-mode, OPCPA technology for Free- Electron Lasers, including, thermal management
Symmetry and Relativity : From Classical Mechanics to Modern Particle Physics
Paris-Sud XI, Université de
Symmetry and Relativity : From Classical Mechanics to Modern Particle Physics Z.J. Ajaltouni Symmetry in Physics and the Relativity Theory, particularly Special Relativity. After a brief historical in the clarification of many issues related to fundamental symmetries. Several examples from classical mechanics
Quantum Monte Carlo methods for nuclear physics
Carlson, Joseph A. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Gandolfi, Stefano [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Pederiva, Francesco [Univ. of Trento (Italy); Pieper, Steven C. [Argonne National Lab. (ANL), Argonne, IL (United States); Schiavilla, Rocco [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Old Dominion Univ., Norfolk, VA (United States); Schmidt, K. E, [Arizona State Univ., Tempe, AZ (United States); Wiringa, Robert B. [Argonne National Lab. (ANL), Argonne, IL (United States)
2012-01-01
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.
Quantum Monte Carlo methods for nuclear physics
J. Carlson; S. Gandolfi; F. Pederiva; Steven C. Pieper; R. Schiavilla; K. E. Schmidt; R. B. Wiringa
2015-04-29
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.
Quantum Monte Carlo methods for nuclear physics
Carlson, Joseph A.; Gandolfi, Stefano; Pederiva, Francesco; Pieper, Steven C.; Schiavilla, Rocco; Schmidt, K. E,; Wiringa, Robert B.
2012-01-01
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
Quantum Monte Carlo methods for nuclear physics
Carlson, Joseph A. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Gandolfi, Stefano [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Pederiva, Francesco [Univ. of Trento (Italy); Pieper, Steven C. [Argonne National Lab. (ANL), Argonne, IL (United States); Schiavilla, Rocco [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Old Dominion Univ., Norfolk, VA (United States); Schmidt, K. E, [Arizona State Univ., Tempe, AZ (United States); Wiringa, Robert B. [Argonne National Lab. (ANL), Argonne, IL (United States)
2012-01-01
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.
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 relaxed style with infectious enthusiasm for his subject, and readily combines formal instruction with physical insight. The result is a serious, pedagogical yet comprehensive guide to the fascinating and important field of one-dimensional quantum systems, for which many a graduate student (and not a few oldies) will be grateful. The first half of the book, chapters 1--5, is devoted to a coherent presentation of the essential concepts and theoretical methods of the field. After a basic introduction to the unique behaviour of interacting electrons in one dimension, and to early fermionic approaches to the problem, Giamarchi turns to the technique of bosonization, introducing chapter 3 with a Marxist quote: `A child of five would understand this. Send for a child of five.' This most powerful technique is presented in a step by step fashion, and serious perusal of the chapter will benefit all ages since bosonization is used extensively throughout the rest of the book. The same is true of chapter 3 where a phenomenological and physically insightful introduction is given to the Luttinger liquid---the key concept in the low-energy physics of one-dimensional systems, analogous to the Fermi liquid in higher dimensions. Chapter 4 deals with what the author calls `refinements', or complications of the sort theorists in particular welcome; such as how the Luttinger liquid description is modified by the presence of long-ranged interactions, the Mott transition (`we forgot the lattice Gromit'), and the effects of breaking spin rotational invariance on application of a magnetic field. Finally chapter 5 describes various microscopic methods for one dimension, including a brief discussion of numerical techniques but focussing primarily on the Bethe ansatz---the famous one-dimensional technique others seek to emulate but whose well known complexity necessitates a relatively brief discussion, confined in practice to the spin-1/2 Heisenberg model. In the second half of the book, chapters 6--11, a range of different physical realizations of one-dimensional quantum physics are dis
Black hole bombs and explosions: from astrophysics to particle physics
Cardoso, Vitor
2013-01-01
Black holes are the elementary particles of gravity, the final state of sufficiently massive stars and of energetic collisions. With a forty-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.
Quantum maximum entropy principle for a system of identical particles
Trovato, M. [Dipartimento di Matematica, Universita di Catania, Viale A. Doria, 95125 Catania (Italy); Reggiani, L. [Dipartimento di Ingegneria dell' Innovazione and CNISM, Universita del Salento, Via Arnesano s/n, 73100 Lecce (Italy)
2010-02-15
By introducing a functional of the reduced density matrix, we generalize the definition of a quantum entropy which incorporates the indistinguishability principle of a system of identical particles. With the present definition, the principle of quantum maximum entropy permits us to solve the closure problem for a quantum hydrodynamic set of balance equations corresponding to an arbitrary number of moments in the framework of extended thermodynamics. The determination of the reduced Wigner function for equilibrium and nonequilibrium conditions is found to become possible only by assuming that the Lagrange multipliers can be expanded in powers of (Planck constant/2pi){sup 2}. Quantum contributions are expressed in powers of (Planck constant/2pi){sup 2} while classical results are recovered in the limit (Planck constant/2pi)->0.
J-PARC Status, Nuclear and Particle Physics
Sato, Susumu [Advanced Science Research Center/J-PARC Center, Japan Atomic Energy Agency, Shirakata-shirane 2-4, Tokai, Ibaraki, 319-1195 (Japan)
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.
Department of Physics & Astronomy Experimental Particle Physics Group
Glasgow, University of
-14 26th July 2004 Wide Bandgap Semiconductor Detectors for Harsh Radiation Environments J. Grant1 , W by radiation induced damage. International Workshop on Radiation Imaging Detectors 2004 University of Glasgow and electronics. Critical systems for nuclear reactors and position sensitive detectors for particle beams
Insights and puzzles in particle physics
H. Leutwyler
2014-10-15
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.
Multiparty quantum key agreement with single particles
NASA Astrophysics Data System (ADS)
Liu, Bin; Gao, Fei; Huang, Wei; Wen, Qiao-yan
2013-04-01
Two conditions must be satisfied in a secure quantum key agreement (QKA) protocol: (1) outside eavesdroppers cannot gain the generated key without introducing any error; (2) the generated key cannot be determined by any non-trivial subset of the participants. That is, a secure QKA protocol can not only prevent the outside attackers from stealing the key, but also resist the attack from inside participants, i.e. some dishonest participants determine the key alone by illegal means. How to resist participant attack is an aporia in the design of QKA protocols, especially the multi-party ones. In this paper we present the first secure multiparty QKA protocol against both outside and participant attacks. Further more, we have proved its security in detail.
Chin-Yi. Tsai
1995-01-01
Theoretical models are presented to study the physical processes of particle dynamics and energy transfer between electrons, holes, photons, LO phonons, and acoustic phonons in high-speed semiconductor quantum well lasers. We simultaneously study the effects of spectral hole burning, carrier heating, and carrier diffusion-capture-escape on the modulation response of the quantum well laser. Our theoretical results indicate that the degradation
Research on elementary particle physics, part 2
NASA Astrophysics Data System (ADS)
Holloway, L. E.
1993-05-01
The activities of the University of Illinois Experimental High Energy Physics Group are described. 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) e(+)e(-) experiments, the Mark III and SLD at SLAC and CLEO at Cornell; (5) CP violation experiments at Fermilab; (6) the HiRes cosmic ray experiment at Dugway Proving Grounds, Utah; (7) computational facilities; and (8) electronics systems development.
Quantum dynamics as a physical resource
Michael A. Nielsen; Christopher M. Dawson; Jennifer L. Dodd; Alexei Gilchrist; Duncan Mortimer; Tobias J. Osborne; Michael J. Bremner; Aram W. Harrow; Andrew Hines
2003-01-13
How useful is a quantum dynamical operation for quantum information processing? Motivated by this question we investigate several strength measures quantifying the resources intrinsic to a quantum operation. We develop a general theory of such strength measures, based on axiomatic considerations independent of state-based resources. The power of this theory is demonstrated with applications to quantum communication complexity, quantum computational complexity, and entanglement generation by unitary operations.
Gauge Theories & Particle Physics Physics 539 Spring Semester 1997 Chris *
Quigg, Chris
. Phys* *. 56, 579 (1984). R. S. Chivukula, M. J. Dugan, M. Golden, and E. H. Simmons, Ann. Rev: On the physics of a supernova: H. A. Bethe and G. Brown, Sci. Am. 252, (Ma* *y, 1985), p. 60. On the U(1) axial anomaly: J. F. Donoghue, E. Golowich, and B. R. Holstein* *, Dynamics of the Standard Model
Department of Physics & Astronomy Experimental Particle Physics Group
Glasgow, University of
vertex trigger. Key words: LHC, Silicon Detector, Radiation Hardness, Trigger PACS: code 29.40.Gx code 29-physics experiment at the LHC, could be signi#12;cantly enhanced by the collection of increased statistics. A future upgrade to the detector is proposed that will allow the experiment to run at signi#12;cantly higher
Santa Cruz Institute for Particle Physics (SCIPP)
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.
Santa Cruz Institute for Particle Physics (SCIPP)
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.
Attention, Intention, and Will in Quantum Physics
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.
Quantum Zeno effect and quantum Zeno paradox in atomic physics
Ellen Block; P. R. Berman
1991-01-01
Itano and co-workers [Wayne M. Itano, D. J. Heinzen, J. J. Bollinger, and D. J. Wineland, Phys. Rev. A 41, 2295 (1990)] have recently reported the experimental verification of the quantum Zeno effect, which is the inhibition of a quantum transition by frequent measurements. In this article, we offer an alternative interpretation of the quantum Zeno effect. We show that
Lagrangian Description for Particle Interpretations of Quantum Mechanics: Single-Particle Case
NASA Astrophysics Data System (ADS)
Sutherland, Roderick I.
2015-06-01
A Lagrangian description is presented which can be used in conjunction with particle interpretations of quantum mechanics. A special example of such an interpretation is the well-known Bohm model. The Lagrangian density introduced here also contains a potential for guiding the particle. The advantages of this description are that the field equations and the particle equations of motion can both be deduced from a single Lagrangian density expression and that conservation of energy and momentum are assured. After being developed in a general form, this Lagrangian formulation is then applied to the special case of the Bohm model as an example. It is thereby demonstrated that such a Lagrangian description is compatible with the predictions of quantum mechanics.
Superfluid Helium 3: Link Between Condensed Matter Physics and Particle Physics
D. Vollhardt; P. Woelfle
2000-01-01
The discovery of the superfluid phases of Helium 3 in 1971 opened the door to one of the most fascinating systems known in condensed matter physics. Superfluidity of Helium 3, originating from pair condensation of Helium 3 atoms, turned out to be the ideal test ground for many fundamental concepts of modern physics, such as macroscopic quantum phenomena, (gauge-)symmetries and
A QuAntum DigitAl universe QuAntum informAtion helps founDAtions of physics
D'Ariano, Giacomo Mauro
A QuAntum DigitAl universe QuAntum informAtion helps founDAtions of physics Giacomo mauro D but to probe the limits of quantum physics, pushing its boundaries both theoretically and experimentally. vol28 scienza in primo piano 1 Introduction: the lesson of Quantum Information Within the history of quantum
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.
Free-Dirac-particle evolution as a quantum random walk
Bracken, A. J. [Centre for Mathematical Physics, Department of Mathematics, University of Queensland, Brisbane 4072 (Australia); Ellinas, D.; Smyrnakis, I. [Department of Sciences, Division of Mathematics, Technical University of Crete, GR 731 00, Chania, Crete (Greece)
2007-02-15
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.
Two-dimensional topological order of kinetically constrained quantum particles
NASA Astrophysics Data System (ADS)
Kourtis, Stefanos; Castelnovo, Claudio
2015-04-01
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 a generalization of strongly interacting particle systems in which hoppings are given by flux-lattice Hamiltonians and may be relevant to optically driven cold-atom systems. After introducing a broad class of models, we focus on particular realizations and show numerically that they exhibit topological order, as witnessed by topological ground-state degeneracies and the quantization of corresponding invariants. These results demonstrate that the correlations responsible for fractional quantum Hall states in lattices can arise in models involving terms other than density-density interactions.
PPARC: The Particle Physics and Astronomy Research Council
NSDL National Science Digital Library
The Particle Physics and Astronomy Research Council (PPARC), the United Kingdom's science investment agency, developed this extensive website to illustrate its work to promote the scientific research and public interest in astronomy, space science, and particle physics. Visitors can find out about the council's numerous projects including the e-science program and the KITE club. Students and researchers can find out about fellowships, training programs, grants, and post-doctoral careers. The website features the educational and public outreach program, Science and Society.
UK Particle Physics, Astronomy, and Space Science (PPARC): Frontiers
NSDL National Science Digital Library
The Frontiers publication offers the latest news and activities of the Research Council's funded projects and the UK Particle Physics, Astronomy, and Space Science's (PPARC) funded scientists. Produced three times a year, each issue is easy to navigate with quick links to the space science and particle physics articles on the Contents page as well as a keyword search. The website offers archives of the publication since 1997. Each issue contains five sections: the Contents, Editorial, Update, Features, and News. While the other sections contain brief synopses, the Features section offers comprehensive descriptions of stimulating endeavors.
Dynamical probability, particle trajectories and completion of traditional quantum mechanics
Tulsi Dass
2005-05-25
Maintaining the position that the wave function $\\psi$ provides a complete description of state, the traditional formalism of quantum mechanics is augmented by introducing continuous trajectories for particles which are sample paths of a stochastic process determined (including the underlying probability space) by $\\psi$. In the resulting formalism, problems relating to measurements and objective reality are solved as in Bohmian mechanics (without sharing its weak points). The pitfalls of Nelson's stochastic mechanics are also avoided.
Quantum, cyclic, and particle-exchange heat engines
NASA Astrophysics Data System (ADS)
Humphrey, T. E.; Linke, H.
2005-10-01
Differences between the thermodynamic behavior of the three-level amplifier (a quantum heat engine based on a thermally pumped laser) and the classical Carnot cycle are usually attributed to the essentially quantum or discrete nature of the former. Here we provide examples of a number of classical and semiclassical heat engines, such as thermionic, thermoelectric and photovoltaic devices, which all utilize the same thermodynamic mechanism for achieving reversibility as the three-level amplifier, namely isentropic (but non-isothermal) particle transfer between hot and cold reservoirs. This mechanism is distinct from the isothermal heat transfer required to achieve reversibility in cyclic engines such as the Carnot, Otto or Brayton cycles. We point out that some of the qualitative differences previously uncovered between the three-level amplifier and the Carnot cycle may be attributed to the fact that they are not the same ‘type’ of heat engine, rather than to the quantum nature of the three-level amplifier per se.
Exotic Statistics for Ordinary Particles in Quantum Gravity
John Swain
2008-05-15
Objects exhibiting statistics other than the familiar Bose and Fermi ones are natural in theories with topologically nontrivial objects including geons, strings, and black holes. It is argued here from several viewpoints that the statistics of ordinary particles with which we are already familiar are likely to be modified due to quantum gravity effects. In particular, such modifications are argued to be present in loop quantum gravity and in any theory which represents spacetime in a fundamentally piecewise-linear fashion. The appearance of unusual statistics may be a generic feature (such as the deformed position-momentum uncertainty relations and the appearance of a fundamental length scale) which are to be expected in any theory of quantum gravity, and which could be testable.
Research program in particle physics. Progress report, January 1, 1992--December 1992
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.
A model of a quantum particle in a quantum environment: a numerical study
R. Carlone; R. Figari; C. Negulescu
2014-07-16
We define and investigate, via numerical analysis, a one dimensional toy-model of a cloud chamber. An energetic quantum particle, whose initial state is a superposition of two identical wave packets with opposite average momentum, interacts during its evolution and exchanges (small amounts of) energy with an array of localized spins. Triggered by the interaction with the environment, the initial superposition state turns into an incoherent sum of two states describing the following situation: or the particle is going to the left and a large number of spins on the left side changed their states, or the same is happening on the right side. This evolution is reminiscent of what happens in a cloud chamber where a quantum particle, emitted as a spherical wave by a radioactive source, marks its passage inside a supersaturated vapour-chamber in the form of a sequence of small liquid bubbles arranging themselves around a possible classical trajectory of the particle.
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.
Detectors for probing relativistic quantum physics beyond perturbation theory
Eric G. Brown; Eduardo Martin-Martinez; Nicolas C. Menicucci; Robert B. Mann
2013-04-30
We develop a general formalism for a non-perturbative treatment of harmonic-oscillator particle detectors in relativistic quantum field theory using continuous-variables techniques. By means of this we forgo perturbation theory altogether and reduce the complete dynamics to a readily solvable set of first-order, linear differential equations. The formalism applies unchanged to a wide variety of physical setups, including arbitrary detector trajectories, any number of detectors, arbitrary time-dependent quadratic couplings, arbitrary Gaussian initial states, and a variety of background spacetimes. As a first set of concrete results, we prove non-perturbatively--and without invoking Bogoliubov transformations--that an accelerated detector in a cavity evolves to a state that is very nearly thermal with a temperature proportional to its acceleration, allowing us to discuss the universality of the Unruh effect. Additionally we quantitatively analyze the problems of considering single-mode approximations in cavity field theory and show the emergence of causal behaviour when we include a sufficiently large number of field modes in the analysis. Finally, we analyze how the harmonic particle detector can harvest entanglement from the vacuum. We also study the effect of noise in time dependent problems introduced by suddenly switching on the interaction versus ramping it up slowly (adiabatic activation).
Wang, Hong-Fu; Zhu, Ai-Dong; Zhang, Shou
2013-05-20
We propose an efficient protocol for optimizing the physical implementation of three-qubit quantum error correction with spatially separated quantum dot spins via virtual-photon-induced process. In the protocol, each quantum dot is trapped in an individual cavity and each two cavities are connected by an optical fiber. We propose the optimal quantum circuits and describe the physical implementation for correcting both the bit flip and phase flip errors by applying a series of one-bit unitary rotation gates and two-bit quantum iSWAP gates that are produced by the long-range interaction between two distributed quantum dot spins mediated by the vacuum fields of the fiber and cavity. The protocol opens promising perspectives for long distance quantum communication and distributed quantum computation networks. PMID:23736467
Linking Quantum Mechanics to Freshman Physics
NASA Astrophysics Data System (ADS)
Vandegrift, Guy
1998-10-01
First-year quantum mechanics can be linked to introductory physics. One example is the Mossbauer effect, which is explained using a simple solution to Schrodinger's equation involving the Dirac delta function. Generalization to N coupled harmonic oscillators shows that the equality of the forces exerted by winner and loser in the game of "tug-of-war" is only an approximation because Newton's third law of motion is not valid (unless phonon momentum is considered). Another example is a treatment of the Gaussian wavepacket which involves less algebra than found in standard textbooks, yet shows that the peak moves according to the familiar equation of motion x = vt + (1/2)at^2 when the applied force is uniform. Finally, a rendition of "Turkey in the Straw" on the viola illustrates Heisenberg's uncertainty principle, which can be written in the less mysterious form, f=(N+-.1)/T , where N cycles are counted in T seconds. Students experience this uncertainty as they try to measure the frequency of a stretched slinky.
Encoded Universality in Physical Implementations of a Quantum Computer
D. Bacon; J. Kempe; D. P. DiVincenzo; D. A. Lidar; K. B. Whaley
2001-04-13
We revisit the question of universality in quantum computing and propose a new paradigm. Instead of forcing a physical system to enact a predetermined set of universal gates (e.g., single-qubit operations and CNOT), we focus on the intrinsic ability of a system to act as a universal quantum computer using only its naturally available interactions. A key element of this approach is the realization that the fungible nature of quantum information allows for universal manipulations using quantum information encoded in a subspace of the full system Hilbert space, as an alternative to using physical qubits directly. Starting with the interactions intrinsic to the physical system, we show how to determine the possible universality resulting from these interactions over an encoded subspace. We outline a general Lie-algebraic framework which can be used to find the encoding for universality and give several examples relevant to solid-state quantum computing.
Time and a physical Hamiltonian for quantum gravity.
Husain, Viqar; Paw?owski, 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
Geometry and Topology of Relativistic Two-Particle Quantum Mixtures
S. Hunzinger; M. Mattes; M. Sorg
2003-01-25
Within the framework of Relativistic Schroedinger Theory (an alternative form of quantum mechanics for relativistic many-particle systems) it is shown that a general N-particle system must occur in one of two forms: either as a ``positive'' or as a ``negative'' mixture, in analogy to the fermion-boson dichotomy of matter in the conventional theory. The pure states represent a limiting case between the two types of mixtures which themselves are considered as the RST counterparts of the entangled (fermionic or bosonic) states of the conventional quantum theory. Both kinds of mixtures are kept separated from dynamical as well as from topological reasons. The 2-particle configurations (N=2) are studied in great detail with respect to their geometric and topological properties which are described in terms of the Euler class of an appropriate bundle connection. If the underlying space-time manifold (as the base space of the fibre bundles applied) is parallelisable, the 2-particle configurations can be thought to be generated geometrically by an appropriate (2+2) splitting of the local tangent space.
Optical Physics of Quantum Wells David A. B. Miller
Miller, David A. B.
Optical Physics of Quantum Wells David A. B. Miller Rm. 4B-401, AT&T Bell Laboratories Holmdel, NJ07733-3030 USA 1 Introduction Quantum wells are thin layered semiconductor structures in which we can) of one semiconductor "well" material sandwiched between other semiconductor "barrier" layers. They can
Quantum Generations: A History of Physics in the Twentieth Century
H. Rechenberg
2000-01-01
The author attempts to handle the most important physics development of the twentieth century, namely that of quantum theory, in one, not too bulky, volume. This heroic task is split into 29 chapters, each treating a topic that forms a well defined subpart of the big theme embracing quantum theory itself (and also some of its companions), and the experimental
Novel Superlattice and Quantum Well Structures: Physics and Device Applications
Perng-Fei Yuh
1989-01-01
The physics and device applications of new superlattice and quantum well structures are studied in this dissertation. A formalism based on the envelope function approximations and the transfer matrix method is developed to analyze the electrical and optical properties of general quantum well structures. This formalism allows the exact and analytical formulation of the eigenenergies and wave functions for an
Quantum dot-containing polymer particles with thermosensitive fluorescence
NASA Astrophysics Data System (ADS)
Generalova, Alla N.; Oleinikov, Vladimir A.; Sukhanova, Alyona; Artemyev, Mikhail V.; Zubov, Vitaly P.; Nabiev, Igor
2012-10-01
In the past decades, increasing attention has been paid to the preparation of "smart" functionalized polymer particles reversibly responding to slight environmental changes, such as variations in temperature, pH, and ionic strength. The composite polymer particles consisting of a solid poly(acrolein-co-styrene) core and a poly(N-vinylcaprolactam) (PVCL) polymer shell doped with CdSe/ZnS semiconductor quantum dots (QDs) were prepared. The thermosensitive response of the composite particles was observed as a decrease in their hydrodynamic diameter upon heating above the lower critical solution temperature of the thermosensitive PVCL polymer used as a shell. Embedding QDs in the PVCL shell makes it possible to obtain particles whose fluorescence is sensitive to temperature changes. The temperature-dependent fluorescence of particles was determined by reversible variation of the distances between QDs in the PVCL shell as a result of temperature-driven conformational changes in this polymer. In addition, these particles can be used as carriers of biomolecule (e.g., bovine serum albumin, BSA) characterized by reversibly temperature-dependent fluorescence, which can serve as the basis for optical detection methods in bioassays, such as the measurement of local temperature in nanovolumes, biosensing, etc.
Magnetic particle motions within living cells. Physical theory and techniques.
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
Solid Polarized Targets for Nuclear and Particle Physics Experiments
D. G. Crabb; W. Meyer
1997-01-01
The development, in the early 1960s, of the dynamic nuclear polarization process in solid diamagnetic materials, doped with paramagnetic radicals, led to the use of solid polarized targets in numerous nuclear and particle physics experiments. Since then steady progress has been made in all contributing subsystems so that proton polarizations near 100% and deuteron polarizations higher than 50% have been
Benefits to Society of Particle Physics Phil Allport
Crowther, Paul
Benefits to Society of Particle Physics Phil Allport 23/11/07 · Overview PP2020 KE Panel spallation, ISIS, Oak Ridge, ESS transmutation energy amplifier sub-critical reactors industrial (Martin Wood, Clarendon, Oxford) MRI, Tesla Fusion programme: IFMIF, ITER RF High Power: (Magnetron
Energetic Particle Instrumentation for Future Space Physics Missions
C. H. Perry; D. K. Griffin; M. W. Dunlop; J. A. Davies; M. A. Hapgood
2009-01-01
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
EUROPEAN ORGANIZATION FOR NUCLEAR RESEARCH European Laboratory for Particle Physics
Paris-Sud XI, Université de
-leak by radiation is reduced by employing multilayer insulation wrapped around the cold mass and an actively cooled-leak by radiation is reduced by employing multilayer insulation wrapped around the cold mass and an actively cooledEUROPEAN ORGANIZATION FOR NUCLEAR RESEARCH European Laboratory for Particle Physics THERMAL
Facilities for spin in particle physics in Japan
NASA Astrophysics Data System (ADS)
Masaike, Akira
1989-05-01
Recent topics on the development of facilities for research on polarization phenomena in the particle physics are reported. Topics included in this report are polarized proton and deuteron targets, slow neutron spin filters, an optically pumped polarized ion source, acceleration of polarized beams at KEK-PS and Tristan, and polarized slow muon beams.
A physically-based particle model of woven cloth
David E. Breen; Donald H. House; Phillip H. Getto
1992-01-01
Every time a tablecloth is draped over a table it will fold and pleat in unique ways. We report on a physically-based model and a simulation methodology, which when used together are able to reproduce many of the attributes of this characteristic behavior of cloth. Our model utilizes a microscopic particle representation that directly treats the mechanical constraints between the
Research in elementary particle physics. [Ohio State Univ. , Columbus
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.
My 50 years of research in particle physics.
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
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.
Multiple particle production processes in the light'' of quantum optics
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.
Physics 139B Quantum Mechanics II Fall 2009 Instructor: Howard Haber
California at Santa Cruz, University of
Physics 139B Quantum Mechanics II Fall 2009 Instructor: Howard Haber Office: ISB, Room 326 Phone OUTSIDE READING: Quantum Physics, by Stephen Gasiorowicz Introduction to Quantum Mechanics, by David J to Quantum Mechanics, by John S. Townsend PREREQUISITES: Physics 116C and Physics 139A. It is assumed
Physics 139B Quantum Mechanics II Fall 2009 Instructor: Howard Haber
California at Santa Cruz, University of
Physics 139B Quantum Mechanics II Fall 2009 Instructor: Howard Haber O#ce: ISB, Room 326 Phone OUTSIDE READING: Quantum Physics, by Stephen Gasiorowicz Introduction to Quantum Mechanics, by David J to Quantum Mechanics, by John S. Townsend PREREQUISITES: Physics 116C and Physics 139A. It is assumed
Quantum cryptography using single-particle entanglement Jae-Weon Lee and Eok Kyun Lee
Lee, EokKyun
Quantum cryptography using single-particle entanglement Jae-Weon Lee and Eok Kyun Lee Department; published 23 July 2003 A quantum cryptography scheme based on entanglement between a single-particle state,2 and quan- tum cryptography 3 . Discussion on the nonlocal nature en- tanglement of quantum systems
Catarina Bastos; Alex E. Bernardini; Jonas F. G. Santos
2014-11-12
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.
Strings as multi-particle states of quantum sigma-models
NASA Astrophysics Data System (ADS)
Gromov, Nikolay; Kazakov, Vladimir; Sakai, Kazuhiro; Vieira, Pedro
2007-02-01
We study the quantum Bethe ansatz equations in the O(2n) sigma-model for physical particles on a circle, with the interaction given by the Zamolodchikovs' S-matrix, in view of its application to quantization of the string on the S×R space. For a finite number of particles, the system looks like an inhomogeneous integrable O(2n) spin chain. Similarly to OSp(2m+n|2m) conformal sigma-model considered by Mann and Polchinski, we reproduce in the limit of large density of particles the finite gap Kazakov-Marshakov-Minahan-Zarembo solution for the classical string and its generalization to the S×R sector of the Green-Schwarz-Metsaev-Tseytlin superstring. We also reproduce some quantum effects: the BMN limit and the quantum homogeneous spin chain similar to the one describing the bosonic sector of the one-loop N=4 super-Yang-Mills theory. We discuss the prospects of generalization of these Bethe equations to the full superstring sigma-model.
Inverse Problems in Classical and Quantum Physics
NASA Astrophysics Data System (ADS)
Almasy, Andrea A.
2009-12-01
The subject of this thesis is in the area of Applied Mathematics known as Inverse Problems. Inverse problems are those where a set of measured data is analysed in order to get as much information as possible on a model which is assumed to represent a system in the real world. We study two inverse problems in the fields of classical and quantum physics: QCD condensates from tau-decay data and the inverse conductivity problem. We use a functional method which allows us to extract within rather general assumptions phenomenological parameters of QCD (the condensates) from a comparison of the time-like experimental data with asymptotic space-like results from theory. The price to be paid for the generality of assumptions is relatively large errors in the values of the extracted parameters. Although we do not claim that our method is superior to other approaches, we hope that our results lend additional confidence to the numerical results obtained with the help of methods based on QCD sum rules. In this thesis, also two approaches of EIT image reconstruction are proposed. The first is based on reformulating the inverse problem in terms of integral equations. This method uses only a single set of measurements for the reconstruction. The second approach is an algorithm based on linearisation which uses more then one set of measurements. A promising result is that one can qualitatively reconstruct the conductivity inside the cross-section of a human chest. Even though the human volunteer is neither two-dimensional nor circular, such reconstructions can be useful in medical applications: monitoring for lung problems such as accumulating fluid or a collapsed lung and noninvasive monitoring of heart function and blood flow.
Janne Mikael Karimäki
2012-06-07
An interpretation of non-relativistic quantum mechanics is presented in the spirit of Erwin Madelung's hydrodynamic formulation of QM and Louis de Broglie's and David Bohm's pilot wave models. The aims of the approach are as follows: 1) to have a clear ontology for QM, 2) to describe QM in a causal way, 3) to get rid of the wave-particle dualism in pilot wave theories, 4) to provide a theoretical framework for describing creation and annihilation of particles, and 5) to provide a possible connection between particle QM and virtual particles in QFT. These goals are achieved, if the wave function is replaced by a fluid of so called virtual particles. It is also assumed that in this fluid of virtual particles exist a few real particles and that only these real particles can be directly observed. This has relevance for the measurement problem in QM and it is found that quantum probabilities arise in a very natural way from the structure of the theory. The model presented here is very similar to a recent computational model of quantum physics and recent Bohmian models of QFT.
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.
Quantum Chaos in Physical Systems: from Super Conductors to Quarks
Elmar Bittner; Harald Markum; Rainer Pullirsch
2001-10-31
This article is the written version of a talk delivered at the Bexbach Colloquium of Science 2000 and starts with an introduction into quantum chaos and its relationship to classical chaos. The Bohigas-Giannoni-Schmit conjecture is formulated and evaluated within random-matrix theory. Several examples of physical systems exhibiting quantum chaos ranging from nuclear to solid state physics are presented. The presentation concludes with recent research work on quantum chromodynamics and the quark-gluon plasma. In the case of a chemical potential the eigenvalue spectrum becomes complex and one has to deal with non-Hermitian random-matrix theory.
An improved quantum-behaved particle swarm optimization algorithm with weighted mean best position
Maolong Xi; Jun Sun; Wenbo Xu
2008-01-01
Quantum-behaved particle swarm optimization (QPSO) algorithm is a global convergence guaranteed algorithms, which outperforms original PSO in search ability but has fewer parameters to control. In this paper, we propose an improved quantum-behaved particle swarm optimization with weighted mean best position according to fitness values of the particles. It is shown that the improved QPSO has faster local convergence speed,
Review for Contemporary Physics Quantum Dialogue
Cheng, Eugenia
of the quantum formalism, especially his own matrix mechanics; and she traces how the conflict between, depending on how one counts). Namely, the idea that the two rival formulations of the new quantum theory--matrix respectively). First, the matrix mechanics school (based in Copenhagen and GÂ¨ottingen) were im- pressed, even
Detection and Survival of a Quantum Particle on a Lattice
Shrabanti Dhar; Subinay Dasgupta; Abhishek Dhar; Diptiman Sen
2014-10-31
We consider a quantum particle, moving on a lattice with a tight-binding Hamiltonian, which is subjected to measurements to detect it's arrival at a particular chosen set of sites. The projective measurements are made at regular time intervals $\\tau$, and we consider the evolution of the wave function till the time a detection occurs. We study the probabilities of its first detection at some time and conversely the probability of it not being detected (i.e., surviving) up to that time. We propose a general perturbative approach for understanding the dynamics which maps the evolution operator, consisting of unitary transformations followed by projections, to one described by a non-Hermitian Hamiltonian. For some examples, of a particle moving on one and two-dimensional lattices with one or more detection sites, we use this approach to find exact expressions for the survival probability and find excellent agreement with exact numerical results. A mean field model with hopping between all pairs of sites and detection at one site is solved exactly. For the one- and two-dimensional systems, the survival probability is shown to have a power-law decay with time, where the power depends on the initial position of the particle. Finally, we show an interesting and non-trivial connection between the dynamics of the particle in our model and the evolution of a particle under a non-Hermitian Hamiltonian with a large absorbing potential at some sites.
The bondons: the quantum particles of the chemical bond.
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 B? characterized by its mass (m(B?)), velocity (v(B?)), charge (e(B?)), and life-time (t(B?)). This is quantized either in ground or excited states of the chemical bond in terms of reduced Planck constant ?, the bond energy E(bond) and length X(bond), 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 B? particle may be observed. Finally, its role in establishing the virtual states in Raman scattering was also established. PMID:21151435
Twenty-Five Centuries of Quantum Physics: From Pythagoras to Us, and from Subjectivism to Realism
NASA Astrophysics Data System (ADS)
Bunge, Mario
Three main theses are proposed. The first is that the idea of a quantum or minimal unit is not peculiar to quantum theory, since it already occurs in the classical theories of elasticity and electrolysis. Second, the peculiarities of the objects described by quantum theory are the following: their basic laws are probabilistic; some of their properties, such as position and energy, are blunt rather than sharp; two particles that were once together continue to be associated even after becoming spatially separated; and the vacuum has physical properties, so that it is a kind of matter. Third, the orthodox or Copenhagen interpretation of the theory is false, and may conveniently be replaced with a realist (though not classicist) interpretation. Heisenberg's inequality, Schrödinger's cat and Zeno's quantum paradox are discussed in the light of the two rival interpretations. It is also shown that the experiments that falsified Bell's inequality do not refute realism but the classicism inherent in hidden variables theories.
Common physical mechanism for integer and fractional quantum Hall effects
Jianhua wang; Kang Li; Shuming Long; Yi Yuan
2012-01-24
Integer and fractional quantum Hall effects were studied with different physics models and explained by different physical mechanisms. In this paper, the common physical mechanism for integer and fractional quantum Hall effects is studied, where a new unified formulation of integer and fractional quantum Hall effect is presented. Firstly, we introduce a 2-dimensional ideal electron gas model in the presence of strong magnetic field with symmetry gauge, and the transverse electric filed $\\varepsilon_2$ is also introduced to balance Lorentz force. Secondly, the Pauli equation is solved where the wave function and energy levels is given explicitly. Thirdly, after the calculation of the degeneracy density for 2-dimensional ideal electron gas system, the Hall resistance of the system is obtained, where the quantum Hall number $\
Studies in theoretical high energy particle physics. Technical progress report, [1991--1992
Aratyn, H.; Brekke, L.; Keung, Wai-Yee; Sukhatme, U.
1993-01-01
Theoretical work on the following topics is briefly summarized: symmetry structure of conformal affine Toda model and KP hierarchy; solitons in the affine Toda and conformal affine Toda models; classical r-matrices and Poisson bracket structures on infinite-dimensional groups; R-matrix formulation of KP hierarchies and their gauge equivalence; statistics of particles and solitons; charge quantization in the presence of an Alice string; knotting and linking of nonabelian flux; electric dipole moments; neutrino physics in gauge theories; CP violation in the high energy colliders; supersymmetric quantum mechanics; parton structure functions in nuclei; dual parton model. 38 refs.
Particle detectors and the zero mode of a quantum field
Eduardo Martin-Martinez; Jorma Louko
2014-07-10
We study the impact of the zero-mode of a quantum field on the evolution of a particle detector. For a massless scalar field in a periodic cavity, we show that the impact of the zero mode on the Unruh-DeWitt detector and its derivative-coupling generalisation is necessarily nonvanishing but can be made negligible in some limits, including those commonly occurring in non-relativistic quantum optics. For the derivative-coupling detector this can be accomplished by just tuning the zero mode's initial state, but the standard Unruh-DeWitt detector requires a more subtle and careful tuning. Applications include an inertial detector with arbitrary velocity, where we demonstrate the regularity of the ultrarelativistic limit, and a detector with uniform acceleration.
Particle physics it matters A forward look at UK research into the building blocks
Crowther, Paul
Particle physics it matters A forward look at UK research into the building blocks physics benefits society Particle physics and healthcare Communications Manufacturing and business Global challenges Helping industry Underpinning the knowledge-based economy Particle physics in the UK Further
why we need it Particle physics is the study of the smallest
Crowther, Paul
why we need it Particle physics is the study of the smallest and most fundamental constituents that occurred fractions of a second after the Big Bang that created our universe. Particle physics and cosmology by increasing the number of children interested in physics. PRodUcing tRained PeoPle Particle physics, astronomy
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…
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…
Proposal for truth particle observable definitions in physics measurements
The ATLAS collaboration
2015-01-01
Measurements and theory predictions at the proton-proton collider LHC become increasingly precise. This makes it necessary to use definitions in the physics measurements that allow for a meaningful comparison of theory and experiment. Moreover, measurements should be defined such that they have a minimal model dependence and that future Monte Carlo simulation can be used for data comparisons. A suitable measurement definition can be based on the stable particles entering the detector. In this note a proposal for the definition of truth particles in the Monte Carlo simulation and observables derived from them is discussed.
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-Fermions. Applications close to experimental realization are proposed in optics, including short light pulse models, waveguides and laser systems, and also in electronics. We hope that this issue will become a valuable reference and inspiration for the broader scientific community working in mathematical and theoretical physics. References [1] Fring A, Jones H F and Znojil M (ed) 2008 J. Phys. A: Math. Theor. 41 240301 [2] Geyer H, Heiss D and Znojil M (ed) 2006 J. Phys. A: Math. Gen. 39 9963
Variance of the quantum dwell time for a nonrelativistic particle
Hahne, G. E. [NASA/Ames Research Center, M. S. 258-6, Moffett Field, California 94035 (United States)] [NASA/Ames Research Center, M. S. 258-6, Moffett Field, California 94035 (United States)
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.
Approximating the physical inner product of Loop Quantum Cosmology
Benjamin Bahr; Thomas Thiemann
2006-07-19
In this article, we investigate the possibility of approximating the physical inner product of constrained quantum theories. In particular, we calculate the physical inner product of a simple cosmological model in two ways: Firstly, we compute it analytically via a trick, secondly, we use the complexifier coherent states to approximate the physical inner product defined by the master constraint of the system. We will find that the approximation is able to recover the analytic solution of the problem, which solidifies hopes that coherent states will help to approximate solutions of more complicated theories, like loop quantum gravity.
Non-Extensive Quantum Statistics with Particle - Hole Symmetry
Biro, T S; Zhang, B W
2015-01-01
Based on Tsallis entropy and the corresponding deformed exponential function, generalized distribution functions for bosons and fermions have been used since a while. However, aiming at a non-extensive quantum statistics further requirements arise from the symmetric handling of particles and holes (excitations above and below the Fermi level). Naive replacements of the exponential function or cut and paste solutions fail to satisfy this symmetry and to be smooth at the Fermi level at the same time. We solve this problem by a general ansatz dividing the deformed exponential to odd and even terms and demonstrate that how earlier suggestions, like the kappa- and q-exponential behave in this respect.
Reflection of a Particle from a Quantum Measurement
Mackrory, Jonathan B; Steck, Daniel A
2010-01-01
We present a generalization of continuous position measurements that accounts for a spatially inhomogeneous measurement strength. This describes many real measurement scenarios, in which the rate at which information is extracted about position has itself a spatial profile, and includes measurements that detect if a particle has crossed from one region into another. We show that such measurements can be described, in their averaged behavior, as stochastically fluctuating potentials of vanishing time average. Reasonable constraints restrict the form of the measurement to have degenerate outcomes, which tend to drive the system to spatial superposition states. We present the results of quantum-trajectory simulations for measurements with a step-function profile (a "which-way" measurement) and a Gaussian profile. We find that the particle can coherently reflect from the measurement region in both cases, despite the stochastic nature of the measurement back-action. In addition, we explore the connection to the qu...
Quantum-like Probabilistic Models outside Physics
Andrei Khrennikov
2007-06-05
We present a quantum-like (QL) model in that contexts (complexes of e.g. mental, social, biological, economic or even political conditions) are represented by complex probability amplitudes. This approach gives the possibility to apply the mathematical quantum formalism to probabilities induced in any domain of science. In our model quantum randomness appears not as irreducible randomness (as it is commonly accepted in conventional quantum mechanics, e.g., by von Neumann and Dirac), but as a consequence of obtaining incomplete information about a system. We pay main attention to the QL description of processing of incomplete information. Our QL model can be useful in cognitive, social and political sciences as well as economics and artificial intelligence. In this paper we consider in a more detail one special application -- QL modeling of brain's functioning. The brain is modeled as a QL-computer.
2T Physics and Quantum Mechanics
W. Chagas-Filho
2008-02-20
We use a local scale invariance of a classical Hamiltonian and describe how to construct six different formulations of quantum mechanics in spaces with two time-like dimensions. All these six formulations have the same classical limit described by the same Hamiltonian. One of these formulations is used as a basis for a complementation of the usual quantum mechanics when in the presence of gravity.
Dick Dalitz:. Examples of His Contributions to Particle Physics
NASA Astrophysics Data System (ADS)
Goldstein, Gary R.
2008-07-01
Dick Dalitz produced lasting contributions to particle physics for 50 years. Along with Dalitz pairs, Dalitz plots and CDD poles, he did major work in parity violation, hyperon resonance identification, the quark model, and hypernuclei. These topics will be summarized, with some emphasis on the author's collaboration with Dalitz on quark spin and fragmentation correlations, and, particularly, the work on the identification of the top quark and its mass. Short biographical information is interspersed. This paper is based on a presentation at the International School of Subnuclear Physics, Erice 2006.
Dick Dalitz: Examples of His Contributions to Particle Physics
Gary R. Goldstein
2007-04-30
Dick Dalitz produced lasting contributions to particle physics for 50 years. Along with Dalitz pairs, Dalitz plots and CDD poles, he did major work in parity violation, hyperon resonance identification, the quark model, and hypernuclei. These topics will be summarized, with some emphasis on the author's collaboration with Dalitz on quark spin and fragmentation correlations, and, particularly, the work on the identification of the top quark and its mass. Short biographical information is interspersed. This paper is based on a presentation at the International School of Subnuclear Physics, Erice 2006.
Physical sputtering of metallic systems by charged-particle impact
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.
MAJOR DETECOTRS IN ELEMENTARY PARTICLE PHYSICS - May 1985 Suppl.
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.
Blasone, Massimo
Path-integral approach to 't Hooft's derivation of quantum physics from classical physics Massimo; published 27 May 2005 We present a path-integral formulation of 't Hooft's derivation of quantum physics to quantum-mechanical sys- tems was recently proposed by 't Hooft 13,14 with subse- quent applications
Particle physics catalysis of thermal Big Bang Nucleosynthesis
Maxim Pospelov
2007-03-15
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 BBN. In particular, we show that the bound states of X^- with helium, formed at temperatures of about T=10^8K, lead to the catalytic enhancement of Li6 production, which is eight orders of magnitude more efficient than the standard channel. In particle physics models where subsequent decay of X^- does not lead to large non-thermal BBN 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 n_{X^-}/s < 3\\times 10^{-17}, which is one of the most stringent probes of electroweak scale remnants known to date.
Active optical fibres in modern particle physics experiments
Carsten Patrick Achenbach
2004-01-01
In modern particle physics experiments wavelength-shifting and scintillating\\u000afibres based on plastic polymers are used for tracking and calorimetry. In this\\u000areview the role of photon trapping efficiencies, transmission functions and\\u000asignal response times for common multimode active fibres is discussed.\\u000aNumerical simulations involving three dimensional tracking of skew rays through\\u000acurved fibres demonstrate the characteristics of trapped light. Of
Jantsch, Axel
are often employed in nuclear and particle physics experimental facilities to accelerate application recognition, nuclear and particle physics ! 1 INTRODUCTION Nuclear and particle physics is a branch of physics colliders. Modern nuclear and particle physics experiments, for example HADES [1] and PANDA [2] at GSI
Theoretical and Experimental Studies of Elementary Particle Physics
Evans, Harold G [Indiana University] [Indiana University; Kostelecky, V Alan [Indiana University] [Indiana University; Musser, James A [Indiana University] [Indiana University
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.
INVESTIGATING HOW STUDENTS THINK ABOUT AND LEARN QUANTUM PHYSICS: AN EXAMPLE FROM TUNNELING
Maine, University of
INVESTIGATING HOW STUDENTS THINK ABOUT AND LEARN QUANTUM PHYSICS: AN EXAMPLE FROM TUNNELING STUDENTS THINK ABOUT AND LEARN QUANTUM PHYSICS: AN EXAMPLE FROM TUNNELING By Jeffrey T. Morgan Thesis, and quantum physics. We describe an investigation into how students reason about quantum mechanical tunneling
The neutron and its role in cosmology and particle physics
Dubbers, Dirk; Schmidt, Michael G. [Physikalisches Institut, Universitaet Heidelberg, Philosophenweg 12, D-69120 Heidelberg (Germany); Institut fuer Theoretische Physik, Universitaet Heidelberg, Philosophenweg 16, D-69120 Heidelberg (Germany)
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 ''first three minutes'' and later on in stellar nucleosynthesis.
The neutron and its role in cosmology and particle physics
NASA Astrophysics Data System (ADS)
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 “first three minutes” and later on in stellar nucleosynthesis.
S. V. Kukhlevsky
2013-06-26
A quasi-unified description of the classical and quantum fields, which defines the electromagnetic, weak and strong interactions, but does not include gravity, is currently possible only in the frame of the Standard Model of Particle Physics (SM) in terms of the gauge symmetry breaking. Part I of the present study has developed the theoretical background for unified description of the all-known classical and quantum fields in terms of the interference between particles and the respective cross-correlation energy, which do not exist from the point of view of quantum mechanics and SM. Part II uses this background for unification of the electromagnetic, weak, strong and gravitational fields and interactions. The unification is performed by generalization of the Einstein energy-mass relation for the interfering unit-fields associated with the interacting particles. The unit-fields obey properties of the point particles and waves of quantum mechanics, the point particles of SM, the strings of theories of strings and the 3-D waves of theories of classical fields.
The Oxford Questions on the foundations of quantum physics
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
The Oxford Questions on the foundations of quantum physics.
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
J. Lamers
2015-06-03
These are lecture notes of an introduction to quantum integrability given at the Tenth Modave Summer School in Mathematical Physics, 2014, aimed at PhD candidates and junior researchers in theoretical physics. We introduce spin chains and discuss the coordinate Bethe ansatz (CBA) for a representative example: the Heisenberg XXZ model. The focus lies on the structure of the CBA and on its main results, deferring a detailed treatment of the CBA for the general $M$-particle sector of the XXZ model to an appendix. Subsequently the transfer-matrix method is discussed for the six-vertex model, uncovering a relation between that model and the XXZ spin chain. Equipped with this background the quantum inverse-scattering method (QISM) and algebraic Bethe ansatz (ABA) are treated. We emphasize the use of graphical notation for algebraic quantities as well as computations. Finally we turn to quantum integrability in the context of theoretical high-energy physics. We discuss factorized scattering in two-dimensional QFT, and conclude with a qualitative introduction to one current research topic relating quantum integrability to theoretical high-energy physics: the Bethe/gauge correspondence.
Putz, Mihai V.
2010-01-01
Within the path integral Feynman formulation of quantum mechanics, the fundamental Heisenberg Uncertainty Relationship (HUR) is analyzed in terms of the quantum fluctuation influence on coordinate and momentum estimations. While introducing specific particle and wave representations, as well as their ratio, in quantifying the wave-to-particle quantum information, the basic HUR is recovered in a close analytical manner for a large range of observable particle-wave Copenhagen duality, although with the dominant wave manifestation, while registering its progressive modification with the factor 1-n2, in terms of magnitude n?[0,1]. of the quantum fluctuation, for the free quantum evolution around the exact wave-particle equivalence. The practical implications of the present particle-to-wave ratio as well as of the free-evolution quantum picture are discussed for experimental implementation, broken symmetry and the electronic localization function. PMID:21152325
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 Doetinchem, H Gast, T Kirn and S Schael Axion searches with helioscopes and astrophysical signatures for axion(-like) particles K Zioutas, M Tsagri, Y Semertzidis, T Papaevangelou, T Dafni and V Anastassopoulos The indirect search for dark matter with IceCube Francis Halzen and Dan Hooper DIRECT DARK MATTER SEARCHES:EXPERIMENTS Gaseous dark matter detectors G Sciolla and C J Martoff Search for dark matter with CRESST Rafael F Lang and Wolfgang Seidel DIRECT AND INDIRECT PARTICLE DARK MATTER SEARCHES:THEORY Dark matter annihilation around intermediate mass black holes: an update Gianfranco Bertone, Mattia Fornasa, Marco Taoso and Andrew R Zentner Update on the direct detection of dark matter in MSSM models with non-universal Higgs masses John Ellis, Keith A Olive and Pearl Sandick Dark stars: a new study of the first stars in the Universe Katherine Freese, Peter Bodenheimer, Paolo Gondolo and Douglas Spolyar Determining the mass of dark matter particles with direct detection experiments Chung-Lin Shan The detection of subsolar mass dark matter halos Savvas M Koushiappas Neutrino coherent scattering rates at direct dark matter detectors Louis E Strigari Gamma rays from dark matter annihilation in the central region of the Galaxy Pasquale Dario Serpico and Dan Hooper DARK MATTER MODELS The dark matter interpretation of the 511 keV line Céline Boehm Axions as dark matter particles Leanne D Duffy and Karl van Bibber Sterile neutrinos Alexander Kusenko Dark matter candidates Lars Bergström Minimal dark matter: model and results Marco Cirelli and Alessandro Strumia Shedding light on the dark sector with direct WIMP production Partha Konar, Kyoungchul Kong, Konstantin T Matchev and Maxim Perelstein Axinos as dark matter particles Laura Covi and Jihn E Kim
Eduardo V. Flores
2013-05-27
Here we propose a model of particles and fields based on the mathematical framework of quantum physics. Our model is an interpretation of quantum physics that treats particles and fields as physically real. We analyze four experiments on wave-particle duality that pose paradoxes. We show that within our model these paradoxes are resolved.
The Physical Principles of Quantum Mechanics. A critical review
F. Strocchi
2012-01-04
The standard presentation of the principles of quantum mechanics is critically reviewed both from the experimental/operational point and with respect to the request of mathematical consistency and logical economy. A simpler and more physically motivated formulation is discussed. The existence of non commuting observables, which characterizes quantum mechanics with respect to classical mechanics, is related to operationally testable complementarity relations, rather than to uncertainty relations. The drawbacks of Dirac argument for canonical quantization are avoided by a more geometrical approach.
Quantum speed limit for physical processes.
Taddei, M M; Escher, B M; Davidovich, L; de Matos Filho, R L
2013-02-01
The evaluation of the minimal evolution time between two distinguishable states of a system is important for assessing the maximal speed of quantum computers and communication channels. Lower bounds for this minimal time have been proposed for unitary dynamics. Here we show that it is possible to extend this concept to nonunitary processes, using an attainable lower bound that is connected to the quantum Fisher information for time estimation. This result is used to delimit the minimal evolution time for typical noisy channels. PMID:23414007
Superluminal Particles, Cosmology and Cosmic-Ray Physics
NASA Astrophysics Data System (ADS)
Gonzalez-Mestres, Luis
2003-07-01
Non-tachyonic superluminal sectors of matter (sup erbradyons), with critical speeds in vacuum much larger than the speed of light, can quite naturally exist and play an important role in both cosmic-ray physics (anomalous high-energy events) and cosmology (big-bang physics, alternatives to inflation, dark matter...). They can even be the real "elementary" particles. An up dated discussion of the sub ject is presented, in relation with recent theoretical and experimental results. Prosp ects for future searches are also reexamined. Lorentz symmetry violation (LSV) models based on mixing with superbradyons are compared with LDRK (linearly deformed relativistic kinematics) and QDRK (quadratically deformed relativistic kinematics) such as defined in our previous paper physics/0003080 .
Physics at the edge of fractional quantum Hall systems
NASA Astrophysics Data System (ADS)
Jolad, Shivakumar
When confined to low dimensions, systems of many interacting particles exhibit phenomenon vastly different from those in three dimensions. Of interest here are electrons in two dimensions placed in a strong perpendicular magnetic field, which exhibit fascinating transport phenomenon called fractional quantum Hall effect (FQHE). The FQHE has been successfully explained by Composite-Fermion (CF) theory. Electrons at the edge of a FQHE state behave as a chiral (unidirectional) one dimensional system of strongly interacting particles, and constitute an example of a class of liquids known as the Tomonaga-Luttinger liquids (TLLs). The theory of TLL is based on a bosonization formalism which exploits a bijective mapping between the fermionic and the bosonic Fock spaces in one dimension. Attempts to describe the FQHE edge through bosonization have had limited success. One such approach, pioneered by X. G. Wen in the early 1990s, predicted certain topological exponents in the electron correlation functions. However, measurement of these exponents showed significant discrepancy with theory, which has been a puzzle for the quantum Hall community for more than a decade, and has served as the motivation for the work performed in the thesis. More specifically, the following issues were investigated: (1) Role of the range of interaction: We have studied the edge excitations and certain matrix elements of electron operator, called spectral weights, for the physical Coulomb interaction as well as for a model short range interaction. We use various methods, such as quantum Monte-Carlo, exact diagonalization and the CF approach, which enables us to study large systems and obtain accurate thermodynamic limits. We find that Wen's effective field theory predictions agree with numerical results for short range interactions, but not for Coulomb interactions. (2) Validity of CF approach for the FQHE edge: We have found a close agreement between the edge spectrum predicted by the CF theory and the exact edge spectrum (as determined by diagonalization) for the nu = 1/3 FQHE state. (3) Edge reconstruction: When certain parameters of the FQHE system, such as the setback distance d between the electron sheet and the background charge, are varied, the competition between electron-electron and the electron-background interaction causes edge reconstruction. We study this physics through the use of the Composite-Fermion diagonalization (CFD) technique and find, consistent with previous numerical studies, that edge reconstruction occurs beyond a critical setback distance d > dc. To accommodate counter propagating boson modes that result from edge reconstruction, we have constructed an effective field theory model with three coupled chiral Luttinger liquids to make predictions for a reconstructed edge. (4) Nonlinearity of spectra: We obtain the thermodynamic dispersion of the edge modes from the CF theory and find that it deviates from linearity in the experimentally measurable energy range, and also exhibits an 'edge magnetoroton' structure in the dispersion relation. We have calculated a transport exponent using the calculated dispersion and find that it is surprisingly insensitive to the nonlinearity as well as to the presence of the edge roton.
Physical interactions of charged particles for radiotherapy and space applications.
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
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…
Fault-tolerant Quantum Communication with Minimal Physical Requirements
L. Childress; J. M. Taylor; A. S. Sorensen; M. D. Lukin
2005-11-11
We describe a novel protocol for a quantum repeater which enables long distance quantum communication through realistic, lossy photonic channels. Contrary to previous proposals, our protocol incorporates active purification of arbitrary errors at each step of the protocol using only two qubits at each repeater station. Because of these minimal physical requirements, the present protocol can be realized in simple physical systems such as solid-state single photon emitters. As an example, we show how nitrogen vacancy color centers in diamond can be used to implement the protocol, using the nuclear and electronic spin to form the two qubits.
Positions for PhD Students (Theoretical Particle Physics, Siegen University)
Siegen, Universität
qf ett qf e Positions for PhD Students (Theoretical Particle Physics, Siegen University" at Siegen and Dortmund Universities invites applications for PhD positions in theoretical particle physics of theoretical particle physics. The Research Unit aims at improving our understanding of fundamental flavour
Author's personal copy Progress in Particle and Nuclear Physics 62 (2009) 468472
Bauer, Wolfgang
2009-01-01
Author's personal copy Progress in Particle and Nuclear Physics 62 (2009) 468472 Contents lists available at ScienceDirect Progress in Particle and Nuclear Physics journal homepage: www.ppnp.2008.12.035 #12;Author's personal copy T. Strother, W. Bauer / Progress in Particle and Nuclear Physics
Two-particle quantum walks applied to the graph isomorphism problem
Gamble, John King; Zhou, Dong; Joynt, Robert; Coppersmith, S N
2010-01-01
We show that the quantum dynamics of interacting and noninteracting quantum particles are fundamentally different in the context of solving a particular computational problem. Specifically, we consider the graph isomorphism problem, in which one wishes to determine whether two graphs are isomorphic (related to each other by a relabeling of the graph vertices), and focus on a class of graphs with particularly high symmetry called strongly regular graphs (SRG's). We study the Green's functions that characterize the dynamical evolution single-particle and two-particle quantum walks on pairs of non-isomorphic SRG's and show that interacting particles can distinguish non-isomorphic graphs that noninteracting particles cannot. We obtain the following specific results: (1) We prove that quantum walks of two noninteracting particles, Fermions or Bosons, cannot distinguish certain pairs of non-isomorphic SRG's. (2) We demonstrate numerically that two interacting Bosons are more powerful than single particles and two n...
An elementary approach to quantum gravity based on a flux model of a physical vacuum
C. L. Herzenberg
2001-06-20
Interactions with ordinary matter of a flux of high-speed uncharged dark matter particles pervasively present in space are examined. In this model, we find that the property of matter that we designate as mass becomes a measure of the interaction cross section of ordinary matter with the flux of dark matter. From this model emerge both a flux-mediated attractive inverse-square force between particles of ordinary matter as well as a characteristic nondeterministic behavior of ordinary matter that originates from statistical variations in the flux. The occurrence of effects similar to gravitational phenomena and effects similar to quantum phenomena in this model may enable a straightforward examination of the convergence of gravitational physics and quantum mechanics.
Elementary particle physics at the University of Florida. Annual report
Field, R.D.; Ramond, P.M.; Sikivie, P. [and others
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.
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)
Path-integral approach to 't Hooft's derivation of quantum physics from classical physics
Blasone, Massimo [Dipartimento di Fisica, Universita di Salerno, Via S.Allende, 84081 Baronissi, SA (Italy); Jizba, Petr [Institute for Theoretical Physics, University of Tsukuba, Ibaraki 305-8571 (Japan) and FNSPE, Czech Technical University, Brehova 7, 115 19 Prague 1 (Czech Republic); Kleinert, Hagen [Institut fuer Theoretische Physik, Freie Universitaet Berlin, Arnimallee 14 D-14195 Berlin (Germany)
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.
Atomic and Molecular Quantum Theory Course Number: C561 3 de Broglie's wave particle duality
Iyengar, Srinivasan S.
Atomic and Molecular Quantum Theory Course Number: C561 3 de Broglie's wave particle duality 1. We, in regards to light. (Newton's corpuscles and Huygens wavefronts). It was the wave nature of particles (instructor) #12;Atomic and Molecular Quantum Theory Course Number: C561 Homework Usain Bolt is now the world
Many particle state and electron noise in quantum systems with a
Fominov, Yakov
Many particle state and electron noise in quantum systems with a localized Coulomb interaction A. V of a single-particle wave packet. Electron-hole excitations and noise #12;Motivation Quantum conductors of the further interest: Wiegner function: Electron occupation numbers: Number of excited electron-hole pairs
DiracQ: A Quantum Many-Body Physics Package
John G. Wright; B. Sriram Shastry
2013-01-20
We present a software package DiracQ, for use in quantum many-body Physics. It is designed for helping with typical algebraic manipulations that arise in quantum Condensed Matter Physics and Nuclear Physics problems, and also in some subareas of Chemistry. DiracQ is invoked within a Mathematica session, and extends the symbolic capabilities of Mathematica by building in standard commutation and anticommutation rules for several objects relevant in many-body Physics. It enables the user to carry out computations such as evaluating the commutators of arbitrary combinations of spin, Bose and Fermi operators defined on a discrete lattice, or the position and momentum operators in the continuum. Some examples from popular systems, such as the Hubbard model, are provided to illustrate the capabilities of the package.
Synthesis of quantum chromodynamics and nuclear physics
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.
"Physical quantity" and " Physical reality" in Quantum Mechanics: an epistemological path
David Vernette; Michele Caponigro
2006-12-05
We reconsider briefly the relation between "physical quantity" and "physical reality in the light of recent interpretations of Quantum Mechanics. We argue, that these interpretations are conditioned from the epistemological relation between these two fundamental concepts. In detail, the choice as ontic level of the concept affect, the relative interpretation. We note, for instance, that the informational view of quantum mechanics (primacy of the subjectivity) is due mainly to the evidence of the "random" physical quantities as ontic element. We will analyze four positions: Einstein, Rovelli, d'Espagnat and Zeilinger.
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;…
Iyengar, Srinivasan S.
Atomic and Molecular Quantum Theory Course Number: C561 25 The Independent particle approximation, Srinivasan S. Iyengar (instructor) #12;Atomic and Molecular Quantum Theory Course Number: C561 3. However, Eq c 2003, Srinivasan S. Iyengar (instructor) #12;Atomic and Molecular Quantum Theory Course Number: C
Atomic and Molecular Quantum Theory Course Number: C561 9 Particle-in-a-box (PIB)
Iyengar, Srinivasan S.
Atomic and Molecular Quantum Theory Course Number: C561 9 Particle-in-a-box (PIB) 1. Consider. Iyengar (instructor) #12;Atomic and Molecular Quantum Theory Course Number: C561 7. Once we study the PIB 2003, Srinivasan S. Iyengar (instructor) #12;Atomic and Molecular Quantum Theory Course Number: C561 10
Non-extensive quantum statistics with particle-hole symmetry
NASA Astrophysics Data System (ADS)
Biró, T. S.; Shen, K. M.; Zhang, B. W.
2015-06-01
Based on Tsallis entropy (1988) and the corresponding deformed exponential function, generalized distribution functions for bosons and fermions have been used since a while Teweldeberhan et al. (2003) and Silva et al. (2010). However, aiming at a non-extensive quantum statistics further requirements arise from the symmetric handling of particles and holes (excitations above and below the Fermi level). Naive replacements of the exponential function or "cut and paste" solutions fail to satisfy this symmetry and to be smooth at the Fermi level at the same time. We solve this problem by a general ansatz dividing the deformed exponential to odd and even terms and demonstrate that how earlier suggestions, like the ?- and q-exponential behave in this respect.
Weak measurement criteria for the past of a quantum particle
B. E. Y. Svensson
2014-08-18
Vaidman, Phys.Rev. A 87, 052104 (2013), has proposed a weak value criterion for the past of a quantum particle, and applied it to photons in a particular setup of nested Mach-Zehnder interferometers. From his analysis, he draws some astonishing conclusions regarding which arms of the setup the photons populate. I argue that the weak values Vaidman employs as weak tracers in his analysis cannot be used in this case and that, consequently, the conclusions he draws cannot be upheld. The reason is that weak values are defined as a limit which in this case turns out to be discontinuous. I propose instead a weak mean value criterion which avoids these shortcomings.
Aerts, Diederik
Published as: Aerts, D., 1994, "Quantum structures, separated physical entities and probability", Found. Phys., 24, 1227 - 1258. Quantum structures, separated physical entities and probability. Diederik is a classical physical entity. This theorem implies that separated quantum entities cannot be described
String theory and the crisis of particle physics II or the ascent of metaphoric arguments
Bert Schroer
2008-06-10
This is a completely reformulated presentation of a previous paper with the same title; this time with a much stronger emphasis on conceptual aspects of string theory and a detailed review of its already more than four decades lasting history within a broader context, including some little-known details. Although there have been several books and essays on the sociological impact and its philosophical implications, there is yet no serious attempt to scrutinize its claims about particle physics using the powerful conceptual arsenal of contemporary local quantum physics. I decided to leave the previous first version on the arXiv because it may be interesting to the reader to notice the change of viewpoint and the reason behind it. Other reasons for preventing my first version to go into print and to rewrite it in such a way that its content complies with my different actual viewpoint can be found at the end of the article. The central message, contained in sections 5 and 6, is that string theory is not what string theorists think and claim it is. The widespread acceptance of a theory whose interpretation has been obtained by metaphoric reasoning had a corroding influence on the rest of particle physics theory as will be illustrated in several concrete cases. The work is dedicated to the memory of Juergen Ehlers with whom I shared many critical ideas, but their formulation in this essay is fully within my responsibility.
Physics as quantum information processing1 Giacomo Mauro D'Ariano
D'Ariano, Giacomo Mauro
Physics as quantum information processing1 Giacomo Mauro D'Ariano QUIT Group, Dipartimento di at the foundations of Physics has been then considered, with space-time, Relativity, quantization rules and Quantum IV, Sezione di Pavia Abstract. The experience from Quantum Information has lead us to look at Quantum
Physics 4, 58 (2011) A long-distance quantum repeater gets one step closer
Shahriar, Selim
2011-01-01
Physics 4, 58 (2011) Viewpoint A long-distance quantum repeater gets one step closer Selim M laws of quantum mechanics. In a paper in Physical Review Letters, Klaus Reim and coauthors [2 a robust, high-fidelity, broadband quantum memory that could be used to realize a long-distance quantum
On the Physical Realizability of a Class of Nonlinear Quantum Systems
Aline I. Maalouf; Ian R. Petersen
2012-07-23
In this paper, the physical realizability property is investigated for a class of nonlinear quantum systems. This property determines whether a given set of nonlinear quantum stochastic differential equations corresponds to a physical nonlinear quantum system satisfying the laws of quantum mechanics.
Observation of quantum particles on a large space-time scale
L. J. Landau
1994-01-01
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 inRv 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.
Unified Theory of Wave-Particle Duality, the Schrödinger Equations, and Quantum Diffraction
Greyson Gilson
2014-09-03
Individual quantum objects display inseparable coexisting wave-like properties and particle-like properties; such inseparable coexistence can seem paradoxical and mind-boggling. The apparent paradox is resolved by the unified theory of wave-particle duality developed in this paper. Based on the unified theory of wave-particle duality, a straightforward derivation of the Schr\\"odinger equations is presented where previously no such derivation was considered to be possible. A new theory of quantum diffraction is subsequently developed.
Ph135a (2011 --2012): "Applications of Quantum Mechanics to Condensed Matter Physics"
Yeh, Nai-Chang
1 Ph135a (2011 -- 2012): "Applications of Quantum Mechanics to Condensed Matter Physics" INSTRUCTOR --------------------------------------------------------------------------------------------------------------------- I. Introduction -- Overview of condensed matter physics. II. Crystalline Structures & Phonons
Ph135a (2012 --2013): "Applications of Quantum Mechanics to Condensed Matter Physics"
Yeh, Nai-Chang
1 Ph135a (2012 -- 2013): "Applications of Quantum Mechanics to Condensed Matter Physics" INSTRUCTOR --------------------------------------------------------------------------------------------------------------------- I. Introduction -- Overview of condensed matter physics. II. Crystalline Structures & Phonons
Particle Physics Catalysis of Thermal Big Bang Nucleosynthesis
Pospelov, Maxim [Perimeter Institute for Theoretical Physics, Waterloo, Ontario N2J 2W9 (Canada); Department of Physics and Astronomy, University of Victoria, Victoria, British Columbia, V8P 1A1 (Canada)
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.
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 ?'s, ?'s, and ?'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.
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.
2010-05-01
We show that the quantum dynamics of interacting and noninteracting quantum particles are fundamentally different in the context of solving a particular computational problem. Specifically, we consider the graph isomorphism problem, in which one wishes to determine whether two graphs are isomorphic (related to each other by a relabeling of the graph vertices), and focus on a class of graphs with particularly high symmetry called strongly regular graphs (SRGs). We study the Green’s functions that characterize the dynamical evolution single-particle and two-particle quantum walks on pairs of nonisomorphic SRGs and show that interacting particles can distinguish nonisomorphic graphs that noninteracting particles cannot. We obtain the following specific results. (1) We prove that quantum walks of two noninteracting particles, fermions or bosons, cannot distinguish certain pairs of nonisomorphic SRGs. (2) We demonstrate numerically that two interacting bosons are more powerful than single particles and two noninteracting particles, in that quantum walks of interacting bosons distinguish all nonisomorphic pairs of SRGs that we examined. By utilizing high-throughput computing to perform over 500 million direct comparisons between evolution operators, we checked all tabulated pairs of nonisomorphic SRGs, including graphs with up to 64 vertices. (3) By performing a short-time expansion of the evolution operator, we derive distinguishing operators that provide analytic insight into the power of the interacting two-particle quantum walk.
Two-particle quantum walks applied to the graph isomorphism problem
Gamble, John King; Friesen, Mark; Zhou Dong; Joynt, Robert; Coppersmith, S. N. [Physics Department, University of Wisconsin--Madison, 1150 University Avenue, Madison, Wisconsin 53706 (United States)
2010-05-15
We show that the quantum dynamics of interacting and noninteracting quantum particles are fundamentally different in the context of solving a particular computational problem. Specifically, we consider the graph isomorphism problem, in which one wishes to determine whether two graphs are isomorphic (related to each other by a relabeling of the graph vertices), and focus on a class of graphs with particularly high symmetry called strongly regular graphs (SRGs). We study the Green's functions that characterize the dynamical evolution single-particle and two-particle quantum walks on pairs of nonisomorphic SRGs and show that interacting particles can distinguish nonisomorphic graphs that noninteracting particles cannot. We obtain the following specific results. (1) We prove that quantum walks of two noninteracting particles, fermions or bosons, cannot distinguish certain pairs of nonisomorphic SRGs. (2) We demonstrate numerically that two interacting bosons are more powerful than single particles and two noninteracting particles, in that quantum walks of interacting bosons distinguish all nonisomorphic pairs of SRGs that we examined. By utilizing high-throughput computing to perform over 500 million direct comparisons between evolution operators, we checked all tabulated pairs of nonisomorphic SRGs, including graphs with up to 64 vertices. (3) By performing a short-time expansion of the evolution operator, we derive distinguishing operators that provide analytic insight into the power of the interacting two-particle quantum walk.
Two-particle quantum walks applied to the graph isomorphism problem
John King Gamble; Mark Friesen; Dong Zhou; Robert Joynt; S. N. Coppersmith
2010-02-16
We show that the quantum dynamics of interacting and noninteracting quantum particles are fundamentally different in the context of solving a particular computational problem. Specifically, we consider the graph isomorphism problem, in which one wishes to determine whether two graphs are isomorphic (related to each other by a relabeling of the graph vertices), and focus on a class of graphs with particularly high symmetry called strongly regular graphs (SRG's). We study the Green's functions that characterize the dynamical evolution single-particle and two-particle quantum walks on pairs of non-isomorphic SRG's and show that interacting particles can distinguish non-isomorphic graphs that noninteracting particles cannot. We obtain the following specific results: (1) We prove that quantum walks of two noninteracting particles, Fermions or Bosons, cannot distinguish certain pairs of non-isomorphic SRG's. (2) We demonstrate numerically that two interacting Bosons are more powerful than single particles and two noninteracting particles, in that quantum walks of interacting bosons distinguish all non-isomorphic pairs of SRGs that we examined. By utilizing high-throughput computing to perform over 500 million direct comparisons between evolution operators, we checked all tabulated pairs of non-isomorphic SRGs, including graphs with up to 64 vertices. (3) By performing a short-time expansion of the evolution operator, we derive distinguishing operators that provide analytic insight into the power of the interacting two-particle quantum walk.
Teaching and understanding of quantum interpretations in modern physics courses Charles Baily1
Colorado at Boulder, University of
Teaching and understanding of quantum interpretations in modern physics courses Charles Baily1 associated impacts on student perspectives regarding quantum physics. We find students are more likely. The Quantum Physics Conceptual Survey (QPCS) [12] is the most recently developed assessment instrument
Implications of computer science principles for quantum physics
Ariel Bendersky; Gonzalo de la Torre; Gabriel Senno; Santiago Figueira; Antonio Acin
2014-07-02
The Church-Turing thesis is one of the pillars of computer science; it postulates that every classical system has equivalent computability power to the so-called Turing machine. While this thesis is crucial for our understanding of computing devices, its implications in other scientific fields have hardly been explored. Here we start this research programme in the context of quantum physics and show that computer science laws have profound implications for some of the most fundamental results of the theory. We first show how they question our knowledge on what a mixed quantum state is, as we identify situations in which ensembles of quantum states defining the same mixed state, indistinguishable according to the quantum postulates, do become distinguishable when prepared by a computer. We also show a new loophole for Bell-like experiments: if some of the parties in a Bell-like experiment use a computer to decide which measurements to make, then the computational resources of an eavesdropper have to be limited in order to have a proper observation of non-locality. Our work opens a new direction in the search for a framework unifying computer science and quantum physics.
The physical nature of very, very small particles and its impact on their behaviour
Othmar Preining
1998-01-01
This paper describes the nature of nanometer particles involving considerations of the kinetic theory of gases, quantum mechanics, and aerosol dynamics. It is shown that particles in the size range below about 5nm contain only few molecules with a high proportion at the surface. Hence, the structure of such particles cannot be regarded as a continuum and the traditional concepts