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1

Note on the physical sense of quantum group particles  

NASA Astrophysics Data System (ADS)

We show that effects of retardation in processes of quasiparticle generation and destruction can be reduced to a deformation of the communication relations for the quasiparticle creation (annihilation) operators. In such an approach the deformation parameter is determined by a retardation time. Similar deformed commutation relations were proposed by Borisov, Ilinski and Uzdin [Phys. Lett. A 169 (1992) 427] when studying the classical and quantum dynamics for the particles in the quantum group representation space. Some generalizations of the deformed commutation relations are given and their physical sense is discussed. Physical problems related to such objects are described.

Ilinski, K. N.; Uzdin, V. M.

1993-03-01

2

Probing models of quantum decoherence in particle physics and cosmology  

NASA Astrophysics Data System (ADS)

In this review we discuss the string theoretical motivations for induced decoherence and deviations from ordinary quantum-mechanical behaviour; this leads to intrinsic CPT violation in the context of an extended class of quantum-gravity models. We proceed to a description of precision tests of CPT symmetry and quantum mechanics using mainly neutral kaons and neutrinos. We emphasize the possibly unique rôle of neutral meson factories in providing tests of models where the quantum-mechanical CPT operator is not well-defined, leading to modifications of Einstein-Podolsky-Rosen particle correlators. Finally, we discuss experimental probes of decoherence in cosmology, including studies of dissipative relaxation models of dark energy in non-critical (non-equilibrium) string theory and the associated modifications of the Boltzmann equation for the evolution of species abundances.

Mavromatos and, Nikolaos E.; Sarkar, Sarben

2007-05-01

3

Concepts of particle physics  

Microsoft Academic Search

This volume elucidates basic and well-established concepts of particle physics for the autodidact who is curious about recent developments in fundamental physics. Elementary quantum mechanics is a background must. Contents, abridged: The evolution of the particle concept before the advent of quantum mechanics. Nonrelativistic quantum mechanics and atomic physics. Relativistic quantum theory. Nuclear phenomena. Subnuclear phenomena. Index.

K. Gottfried; V. F. Weisskopf

1984-01-01

4

Quantum Optics, Diffraction Theory, and Elementary Particle Physics  

ScienceCinema

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

5

Quantum Physics  

Microsoft Academic Search

In Quantum Mechanics operators must be hermitian and, in a direct product space, symmetric. These properties are saved by Lie algebra operators but not by those of quantum algebras. A possible correspondence between observables and quantum algebra operators is suggested by extending the definition of matrix el- ements of a physical observable, including the eventual projection on the appro- priate

E. Celeghini; M. A. del Olmo

1969-01-01

6

Particle Physics  

Microsoft Academic Search

A few years ago, when some of us were working to introduce particle physics into A-level courses, I exchanged letters with a professor of particle physics who expressed the view that we would not succeed in our aims, on the grounds that there were no textbooks that treated particle physics at an appropriate level. Our opinion at the time was

E Swinbank

1998-01-01

7

Quantum Concepts in Physics  

NASA Astrophysics Data System (ADS)

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

Longair, Malcolm

2013-01-01

8

Quantum Physics for Beginners.  

ERIC Educational Resources Information Center

|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)|

Strand, J.

1981-01-01

9

Research in theoretical particle physics  

SciTech Connect

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)

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

1992-05-01

10

Interpretation of Quantum Physics  

Microsoft Academic Search

ATTENTION has been directed to persistent questions of interpretation in quantum physics by the recent exchange of views1 on the subject between Dr. H. V. Stopes-Roe and Prof. A. Landé. To Prof. Landé's picture2 of the particle as permanently localized phenomenon, influenced through action-at-a-distance by the extended structure of a measuring instrument, Dr. Stopes-Roe understandably objects that a necessarily detailed

T. E. Phipps

1962-01-01

11

Review of Particle Physics  

NASA Astrophysics Data System (ADS)

This biennial Review summarizes much of particle physics. Using data from previous editions, plus 2658 new measurements from 644 papers, we list, evaluate, and average measured properties of gauge bosons, leptons, quarks, mesons, and baryons. We 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 112 reviews are many that are new or heavily revised including those on Heavy-Quark and Soft-Collinear Effective Theory, Neutrino Cross Section Measurements, Monte Carlo Event Generators, Lattice QCD, Heavy Quarkonium Spectroscopy, Top Quark, Dark Matter, Vcb & Vub, Quantum Chromodynamics, High-Energy Collider Parameters, Astrophysical Constants, Cosmological Parameters, and Dark Matter.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/.The 2012 edition of Review of Particle Physics is published for the Particle Data Group as article 010001 in volume 86 of Physical Review D.This edition should be cited as: J. Beringer et al. (Particle Data Group), Phys. Rev. D 86, 010001 (2012).

Beringer, J.; Arguin, J.-F.; Barnett, R. M.; Copic, K.; Dahl, O.; Groom, D. E.; Lin, C.-J.; Lys, J.; Murayama, H.; Wohl, C. G.; Yao, W.-M.; Zyla, P. A.; Amsler, C.; Antonelli, M.; Asner, D. M.; Baer, H.; Band, H. R.; Basaglia, T.; Bauer, C. W.; Beatty, J. J.; Belousov, V. I.; Bergren, E.; Bernardi, G.; Bertl, W.; Bethke, S.; Bichsel, H.; Biebel, O.; Blucher, E.; Blusk, S.; Brooijmans, G.; Buchmueller, O.; Cahn, R. N.; Carena, M.; Ceccucci, A.; Chakraborty, D.; Chen, M.-C.; Chivukula, R. S.; Cowan, G.; D'Ambrosio, G.; Damour, T.; de Florian, D.; de Gouvêa, A.; DeGrand, T.; de Jong, P.; Dissertori, G.; Dobrescu, B.; Doser, M.; Drees, M.; Edwards, D. A.; Eidelman, S.; Erler, J.; Ezhela, V. V.; Fetscher, W.; Fields, B. D.; Foster, B.; Gaisser, T. K.; Garren, L.; Gerber, H.-J.; Gerbier, G.; Gherghetta, T.; Golwala, S.; Goodman, M.; Grab, C.; Gritsan, A. V.; Grivaz, J.-F.; Grünewald, M.; Gurtu, A.; Gutsche, T.; Haber, H. E.; Hagiwara, K.; Hagmann, C.; Hanhart, C.; Hashimoto, S.; Hayes, K. G.; Heffner, M.; Heltsley, B.; Hernández-Rey, J. J.; Hikasa, K.; Höcker, A.; Holder, J.; Holtkamp, A.; Huston, J.; Jackson, J. D.; Johnson, K. F.; Junk, T.; Karlen, D.; Kirkby, D.; Klein, S. R.; Klempt, E.; Kowalewski, R. V.; Krauss, F.; Kreps, M.; Krusche, B.; Kuyanov, Yu. V.; Kwon, Y.; Lahav, O.; Laiho, J.; Langacker, P.; Liddle, A.; Ligeti, Z.; Liss, T. M.; Littenberg, L.; Lugovsky, K. S.; Lugovsky, S. B.; Mannel, T.; Manohar, A. V.; Marciano, W. J.; Martin, A. D.; Masoni, A.; Matthews, J.; Milstead, D.; Miquel, R.; Mönig, K.; Moortgat, F.; Nakamura, K.; Narain, M.; Nason, P.; Navas, S.; Neubert, M.; Nevski, P.; Nir, Y.; Olive, K. A.; Pape, L.; Parsons, J.; Patrignani, C.; Peacock, J. A.; Petcov, S. T.; Piepke, A.; Pomarol, A.; Punzi, G.; Quadt, A.; Raby, S.; Raffelt, G.; Ratcliff, B. N.; Richardson, P.; Roesler, S.; Rolli, S.; Romaniouk, A.; Rosenberg, L. J.; Rosner, J. L.; Sachrajda, C. T.; Sakai, Y.; Salam, G. P.; Sarkar, S.; Sauli, F.; Schneider, O.; Scholberg, K.; Scott, D.; Seligman, W. G.; Shaevitz, M. H.; Sharpe, S. R.; Silari, M.; Sjöstrand, T.; Skands, P.; Smith, J. G.; Smoot, G. F.; Spanier, S.; Spieler, H.; Stahl, A.; Stanev, T.; Stone, S. L.; Sumiyoshi, T.; Syphers, M. J.; Takahashi, F.; Tanabashi, M.; Terning, J.; Titov, M.; Tkachenko, N. P.; Törnqvist, N. A.; Tovey, D.; Valencia, G.; van Bibber, K.; Venanzoni, G.; Vincter, M. G.; Vogel, P.; Vogt, A.; Walkowiak, W.; Walter, C. W.; Ward, D. R.; Watari, T.; Weiglein, G.; Weinberg, E. J.; Wiencke, L. R.; Wolfenstein, L.; Womersley, J.; Woody, C. L.; Workman, R. L.; Yamamoto, A.; Zeller, G. P.; Zenin, O. V.; Zhang, J.; Zhu, R.-Y.; Harper, G.; Lugovsky, V. S.; Schaffner, P.

2012-07-01

12

Interpreting Quantum Particles as Conceptual Entities  

Microsoft Academic Search

We elaborate an interpretation of quantum physics founded on the hypothesis that quantum particles are conceptual entities\\u000a playing the role of communication vehicles between material entities composed of ordinary matter which function as memory\\u000a structures for these quantum particles. We show in which way this new interpretation gives rise to a natural explanation for\\u000a the quantum effects of interference and

Diederik Aerts

2010-01-01

13

Quantum Physics in School.  

ERIC Educational Resources Information Center

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

Lawrence, I.

1996-01-01

14

Going from classical to quantum description of bound charged particles II: Implications for the atomic physics  

NASA Astrophysics Data System (ADS)

This paper is the continuation of the analysis of bound quantum systems started in part I (A.L. Kholmetskii, T. Yarman and O.V. Missevitch, Going from classical to quantum description of bound charged particles. I: Basic concepts and assertions), which is based on a novel approach to the transition from classical to quantum description of electrically bound charges, involving the requirement of energy-momentum conservation for the bound electromagnetic (EM) field, when the EM radiation is forbidden. It has been shown that the modified expression for the energy levels of hydrogenic atoms within such a pure bound field theory (PBFT) provides the same gross and fine structure of energy levels, like in the standard theory. At the same time, at the scale of hyperfine interactions, our approach, in general, does evoke some important corrections to the energy levels. Part of such corrections, like the spin-spin splitting in the hydrogen atom, is less than the present theoretical/experimental uncertainties in the evaluation of hyperfine contributions into the atomic levels. But the most interesting result is the appearance of a number of significant corrections (the 1 S -2 S interval and 1 S spin-spin interval in positronium, 1 S and 2 S -2 P Lamb shift in light hydrogenic atoms), which improve considerably the convergence between theoretical predictions and experimental results. In particular, the corrected 1 S -2 S interval and 1 S spin-spin splitting in positronium practically eliminate the existing up-to-date discrepancy between theoretical and experimental data. The re-estimated classic 2 S -2 P Lamb shift as well as ground-state Lamb shift in the hydrogen atom lead to the proton charge radius r p = 0.841(6) fm (from 2 S -2 P Lamb shift), and r p = 0.846(22) fm (from 1 S Lamb shift), which perfectly agrees with the latest estimation of proton size via the measurement of 2 S -2 P Lamb shift in muonic hydrogen, i.e. r p = 0.84184(67) fm. Finally, we consider the decay of bound muons in meso-atoms and achieve a quantitative agreement between experimental data and the results obtained through our approach.

Kholmetskii, A. L.; Yarman, T.; Missevitch, O. V.

2011-04-01

15

The Birth of Elementary-Particle Physics.  

ERIC Educational Resources Information Center

|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)|

Brown, Laurie M.; Hoddeson, Lillian

1982-01-01

16

Correlations in Quantum Physics  

NASA Astrophysics Data System (ADS)

We provide a historical perspective of how the notion of correlations has evolved within quantum physics. We begin by reviewing Shannon's information theory and its first application in quantum physics, due to Everett, in explaining the information conveyed during a quantum measurement. This naturally leads us to Lindblad's information theoretic analysis of quantum measurements and his emphasis of the difference between the classical and quantum mutual information. After briefly summarizing the quantification of entanglement using these ideas, we arrive at the concept of quantum discord, which naturally captures the boundary between entanglement and classical correlations. Finally we discuss possible links between discord, which the generation of correlations in thermodynamic transformations of coupled harmonic oscillators.

Dorner, Ross; Vedral, Vlatko

2013-01-01

17

Physicalism Versus Quantum Mechanics  

Microsoft Academic Search

The widely held philosophical position called “physicalism” has been described and defended in a recent book by Jaegwon Kim.\\u000a The physicalist position claims that the world is basically purely physical. However, “physical” is interpreted in a way predicated,\\u000a in effect, upon certain properties of classical physics that are contradicted by the precepts of orthodox quantum physics.\\u000a Kim’s arguments reveal two

Henry P. Stapp

18

Quantum Physics: Introduction  

NSDL National Science Digital Library

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.

Stern, David

2005-11-09

19

Insights into students' understanding of quantum physics: visualizing quantum entities  

NASA Astrophysics Data System (ADS)

Ninety years after the genesis of quantum physics significant research on students' understanding of such revolutionary phenomena is beginning to emerge. What are photons really like? Are they like particles or waves? Are they like both particles and waves, or like neither? The implications of quantum theory for the commonsense notion of an object illustrate the difficulties in using ordinary experience to make sense of the subatomic world. Part of the findings of a series of studies investigating students' understanding of quantum physics is presented, describing students' visualizations of quantum entities (i.e. electrons and photons).

Mashhadi, Azam; Woolnough, Brian

1999-11-01

20

Review of Particle Physics  

Microsoft Academic Search

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

C. Amsler; M. Doser; M. Antonelli; D. M. Asner; K. S. Babu; H. Baer; H. R. Band; R. M. Barnett; E. Bergren; J. Beringer; G. Bernardi; W. Bertl; H. Bichsel; O. Biebel; P. Bloch; E. Blucher; S. Blusk; R. N. Cahn; M. Carena; C. Caso; A. Ceccucci; D. Chakraborty; M.-C. Chen; R. S. Chivukula; G. Cowan; O. Dahl; G. D'Ambrosio; T. Damour; A. de Gouvêa; T. DeGrand; B. Dobrescu; M. Drees; D. A. Edwards; S. Eidelman; V. D. Elvira; J. Erler; V. V. Ezhela; J. L. Feng; W. Fetscher; B. D. Fields; B. Foster; T. K. Gaisser; L. Garren; H.-J. Gerber; G. Gerbier; T. Gherghetta; G. F. Giudice; M. Goodman; C. Grab; A. V. Gritsan; J.-F. Grivaz; D. E. Groom; M. Grünewald; A. Gurtu; T. Gutsche; H. E. Haber; K. Hagiwara; C. Hagmann; K. G. Hayes; J. J. Hernández-Rey; K. Hikasa; I. Hinchliffe; A. Höcker; J. Huston; P. Igo-Kemenes; J. D. Jackson; K. F. Johnson; T. Junk; D. Karlen; B. Kayser; D. Kirkby; S. R. Klein; I. G. Knowles; C. Kolda; R. V. Kowalewski; P. Kreitz; B. Krusche; Yu. V. Kuyanov; Y. Kwon; O. Lahav; P. Langacker; A. Liddle; Z. Ligeti; C.-J. Lin; T. M. Liss; L. Littenberg; J. C. Liu; K. S. Lugovsky; H. Mahlke; M. L. Mangano; T. Mannel; A. V. Manohar; W. J. Marciano; A. D. Martin; A. Masoni; D. Milstead; R. Miquel; K. Mönig; H. Murayama; K. Nakamura; M. Narain; P. Nason; S. Navas; P. Nevski; Y. Nir; K. A. Olive; L. Pape; C. Patrignani; J. A. Peacock; G. Punzi; A. Quadt; S. Raby; G. Raffelt; B. N. Ratcliff; B. Renk; P. Richardson; S. Roesler; A. Romaniouk; L. J. Rosenberg; C. T. Sachrajda; Y. Sakai; S. Sarkar; F. Sauli; O. Schneider; D. Scott; W. G. Seligman; M. H. Shaevitz; T. Sjöstrand; J. G. Smith; S. Spanier; H. Spieler; A. Stahl; T. Stanev; S. L. Stone; T. Sumiyoshi; M. Tanabashi; J. Terning; M. Titov; N. P. Tkachenko; N. A. Törnqvist; D. Tovey; G. H. Trilling; T. G. Trippe; G. Valencia; K. van Bibber; M. G. Vincter; P. Vogel; D. R. Ward; T. Watari; B. R. Webber; G. Weiglein; J. D. Wells; M. Whalley; A. Wheeler; C. G. Wohl; L. Wolfenstein; J. Womersley; C. L. Woody; R. L. Workman; A. Yamamoto; W.-M. Yao; O. V. Zenin; J. Zhang; R.-Y. Zhu; P. A. Zyla; G. Harper; V. S. Lugovsky; P. Schaffner

2008-01-01

21

Finite groups and quantum physics  

NASA Astrophysics Data System (ADS)

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

Kornyak, V. V.

2013-02-01

22

Quantum Physical Symbol Systems  

Microsoft Academic Search

Today's theories of computing and machine learning developed within a nineteenth-century mechanistic mindset. Although digital computers would be impossible without quantum physics, their physical and logical architecture is based on the view of a computer as an automaton executing pre-programmed sequences of operations exactly as instructed. Recent innovations in representations and algorithms suggest that a shift in viewpoint may be

Kathryn Blackmond Laskey

2006-01-01

23

Quantum Properties of Fluids and Solids, Physics and Interacting Particles and Fields.  

National Technical Information Service (NTIS)

The report provides a summary of the research progress and activities for the period from 1 June 1971 to 30 June 1973. Research was carried out in the following areas: Intermediate Energy Physics - Semi-leptonic weak and electromagnetic interactions with ...

A. L. Fetter J. D. Walecka

1973-01-01

24

Quantum entanglement and entropy in particle creation  

SciTech Connect

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

Lin, S.-Y. [Department of Physics, National Cheng Kung University and Physics Division, National Center for Theoretical Sciences (South), Tainan 70101, Taiwan (China); Department of Physics, National Changhua University of Education, Changhua 50007, Taiwan (China); Chou, C.-H. [Department of Physics, National Cheng Kung University and Physics Division, National Center for Theoretical Sciences (South), Tainan 70101, Taiwan (China); Hu, B. L. [Joint Quantum Institute and Maryland Center for Fundamental Physics, University of Maryland, College Park, Maryland 20742-4111 (United States)

2010-04-15

25

Foundations of quantum physics  

Microsoft Academic Search

An enquiry is made on a more fundamental level about the origin of the superposition principle and thus to justify the use of Hilbert space without appeal at the outset to the notion of probability. In doing so there was also a search made for a more general formulation of quantum physics to avoid the apparent paradox of the usual

C. Piron

1976-01-01

26

Quantum physics meets biology  

Microsoft Academic Search

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,

Markus Arndt; Thomas Juffmann; Vlatko Vedral

2009-01-01

27

Buddhism and Quantum Physics  

Microsoft Academic Search

Rudyard Kipling, the famous English author of The Jungle Book, born in India, wrote one day these words: ‘Oh, East is East and West is West, and never the twain shall meet’. In my paper I show that Kipling was not completely right. I try to show the common ground between Buddhist philosophy and quantum physics. There is a surprising

Christian Thomas Kohl

2007-01-01

28

Quantum aspects of beam physics  

Microsoft Academic Search

The continued demand for higher beam energies, luminosities, and brightness, induces increasing number of beam phenomena that involve quantum effects. In this paper we review the various quantum aspects of beam physics, with emphasis on their recent advances. These include quantum effects in beam dynamics, electron-photon interaction, beam phenomena under strong fields, fundamental physics under violent acceleration, and quantum methodology

Pisin Chent

1999-01-01

29

Consciousness, Causality, and Quantum Physics  

Microsoft Academic Search

Quantum theory is open to different interpretations, and this paper reviews some of the points of contention. The standard interpretation of quantum physics assumes that the quantum world is characterized by ab- solute indeterminism and that quantum systems exist objectively only when they are being measured or observed. David Bohm's ontological interpreta- tion of quantum theory rejects both these assumptions.

DAVID PRATT

1997-01-01

30

PARTICLE PHYSICS THEORY GROUP  

Microsoft Academic Search

Particle Physics seeks to identify the elementary consti- tuents of nature and to discover the fundamental forces acting between these constituents. Ordinary matter and non-gra- vitational interactions are described by the Standard Model which comprises two kinds of matter particles (quarks and leptons), three fundamental forces (the strong, electromag- netic and weak interactions) and the Higgs sector as the ori-

H. Pichl; R. Rosenfelder; M. Spira; R. Unterdorfer; J. Urban; M. Walser; L. Wieders; M. Weber

31

Quantum Physics and Reality  

Microsoft Academic Search

Contrary to classical physics, which was strongly objective i.e. could be interpreted as a description of mind-independent\\u000a reality, standard quantum mechanics (SQM) is only weakly objective, that is to say, its statements, though intersubjectively\\u000a valid, still merely refer to operations of the mind. Essentially, in fact, they are predictive of observations. On the view\\u000a that SQM is universal conventional realism

Bernard d’Espagnat

32

Cosmology and Particle Physics  

NASA Astrophysics Data System (ADS)

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

Steigman, G.

1982-01-01

33

Quantum statistics of composite particles  

Microsoft Academic Search

Elementary particles are defined such that (a) elementary particles are indistinguishable (indistinguishability) and (b) particles can combine, in arbitrary number, to form a composite. The resulting composite must be either a boson or a fermion (elementarity). The quantum statistics of a composite particle will be studied by looking at the center-of-mass motion. We postulate that the center-of-mass moves following general

David Louis Morabito

1998-01-01

34

Detecting the relative localisation of quantum particles  

NASA Astrophysics Data System (ADS)

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

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

2013-06-01

35

Physical Constructivism and Quantum Probability  

NASA Astrophysics Data System (ADS)

I describe the main ideas of constructive physics and its role for the probability interpretation of quantum theory. It is shown how the explicit probability space for quantum systems gives the formal representation of entanglement and decoherence.

Ozhigov, Yu. I.

2009-03-01

36

Spin in Particle Physics  

NASA Astrophysics Data System (ADS)

Preface; 1. Spin and helicity; 2. The effect of Lorentz and discrete transformations on helicity states, fields and wave-functions; 3. The spin density matrix; 4. Transition amplitudes; 5. The observables of a reaction; 6. The production of polarized hadrons; 7. The production of polarized e±; 8. Analysis of polarized states: polarimetry; 9. Electroweak interactions; 10. Quantum chromodynamics: spin in the world of massless partons; 11. The spin of the nucleon: polarized deep inelastic scattering; 12. Two-spin and parity-violating single spin asymmetries at large scale; 13. One particle inclusive transverse single-spin asymmetries; 14. Elastic scattering at high energies; Appendices.

Leader, Elliot

2001-07-01

37

Spin in Particle Physics  

NASA Astrophysics Data System (ADS)

Preface; 1. Spin and helicity; 2. The effect of Lorentz and discrete transformations on helicity states, fields and wave-functions; 3. The spin density matrix; 4. Transition amplitudes; 5. The observables of a reaction; 6. The production of polarized hadrons; 7. The production of polarized e±; 8. Analysis of polarized states: polarimetry; 9. Electroweak interactions; 10. Quantum chromodynamics: spin in the world of massless partons; 11. The spin of the nucleon: polarized deep inelastic scattering; 12. Two-spin and parity-violating single spin asymmetries at large scale; 13. One particle inclusive transverse single-spin asymmetries; 14. Elastic scattering at high energies; Appendices.

Leader, Elliot

2005-10-01

38

Physics as quantum information processing: Quantum fields as quantum automata  

NASA Astrophysics Data System (ADS)

Can we reduce Quantum Field Theory (QFT) to a quantum computation? Can physics be simulated by a quantum computer? Do we believe that a quantum field is ultimately made of a numerable set of quantum systems that are unitarily interacting? A positive answer to these questions corresponds to substituting QFT with a theory of quantum cellular automata (QCA), and the present work is examining this hypothesis. These investigations are part of a large research program on a quantum-digitalization of physics, with Quantum Theory as a special theory of information, and Physics as emergent from the same quantum-information processing. A QCA-based QFT has tremendous potential advantages compared to QFT, being quantum ab-initio and free from the problems plaguing QFT due to the continuum hypothesis. Here I will show how dynamics emerges from the quantum processing, how the QCA can reproduce the Dirac-field phenomenology at large scales, and the kind of departures from QFT that that should be expected at a Planckscale discreteness. I will introduce the notions of linear field quantum automaton and local-matrix quantum automaton, in terms of which I will provide the solution to the Feynman's problem about the possibility of simulating a Fermi field with a quantum computer.

D'Ariano, Giacomo Mauro

2012-03-01

39

Quantum Physics Online: Wave Mechanics  

NSDL National Science Digital Library

This is a set of interactive Java applets illustrating the wave nature of quantum physics. Animations are used to illustrate propagation of wave packets, and scattering from potentials. There is also a simple illustration of a scanning tunneling microscope. These applets are part of an extensive collection of animations and simulations illustrating a large range of quantum topics, and an ongoing effort for developing a fully interactive quantum-physics class. Both French and English versions are available.

Joffre, Manuel

2004-03-28

40

Elementary particle physics: Experimental  

NASA Astrophysics Data System (ADS)

A research program was performed in high energy experimental particle physics. Studies of high energy hadronic interactions and leptoproduction processes continue using several experimental techniques. Progress was made on the study of multiparticle production processes in nuclei. Ultra-high energy cosmic ray nucleus-nucleus interactions were investigated by the Japanese American Cosmic Emulsion Experiment (JACEE) using balloon-borne emulsion chamber detectors. In the area of particle astrophysics, studies of cosmic ray nuclear interactions made possible the use of the world's most accurate determination of the comparison of the cosmic rays above 10(exp 13)eV. It is the only detector that can observe interaction vertices and identify particles at energies up to 10 to 15 eV. The observations are getting close to placing limits on the acceleration mechanisms postulated for pulsars in which the spin and magnetic moment axes are at different angles. In June, 1989 approval was given by NASA for our participation in the Space Station program. The SCINATT experiment will make use of emulsion chamber detectors, similar to the planned JACEE hybrid balloon flight detectors. These detector will permit precise determination of secondary particle charges, momenta and rapidities, and the accumulation of data will be at least a factor of 10 to 100 greater than in balloon experiments. Emulsion chamber techniques are also employed in an experiment using accelerator heavy ion beams at CERN and Brookhaven National Laboratory to investigate particle production processes in central collisions of nuclei in the energy range 15 to 200A GeV. The study of hadroproduction in lepton interactions is continuing with approval of another 8 months run for deep inelastic muon scattering experiment E665 at Fermilab.

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

1989-09-01

41

Testing Quantum Mechanics in High-Energy Physics  

NASA Astrophysics Data System (ADS)

In this set of lectures we show that particle physics can also contribute to fundamental questions about quantum mechanics (QM) and even shine new light in the fine workings of quantum physics and this at scales of energies which are not available for usual quantum systems. In particular the massive meson-antimeson systems are specially suitable as they offer a unique laboratory to test various aspects of particle physics (CP violation, CPT violation, etc.) as well as to test the foundations of QM (local realistic theories versus QM, Bell inequalities, decoherence effects, quantum marking and erasure concepts, Bohr's complementary relation, etc.).

Hiesmayr, Beatrix C.

42

Teaching Quantum Physics without Paradoxes  

ERIC Educational Resources Information Center

|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…

Hobson, Art

2007-01-01

43

Operational Quantum Physics  

Microsoft Academic Search

This tome is a formal presentation of the unsharp observable approach to quantum mechanics using the positive operator valued (POV) concept of an observable. It is intended for philosophers and mathematicians as well as physicists. This is a very formalistic book. There are, however, portions that should be read by all experimentalists performing quantum mechanical studies as well as graduate

J L Safko

1996-01-01

44

Quantum physics and computers  

Microsoft Academic Search

Recent theoretical results confirm that quantum theory provides the possibility of new ways of performing efficient calculations. The most striking example is the factoring problem. It has recently been shown that computers that exploit quantum features could factor large composite integers. This task is believed to be out of reach of classical computers as soon as the number of digits

Adriano Barenco

1996-01-01

45

Particle physics---Experimental  

SciTech Connect

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

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

1991-08-21

46

Particle physics: Experimental  

NASA Astrophysics Data System (ADS)

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.

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

1991-08-01

47

Quantum Hall physics with light  

NASA Astrophysics Data System (ADS)

Quantum Hall physics provides a variety of novel phenomena in both the integer and fractional domain, with applications in metrology, technology, and quantum computation. I will discuss implementing quantum Hall physics with optical systems by means of synthetic gauge fields and photon-photon interactions. First, in the integer quantum Hall regime, I consider our theoretical and experimental efforts using established photonics technology to see expected phenomena, such as edge states of light. I will then consider the nonlinear regime, where photon-photon interactions via optical or microwave nonlinearities enable the potential realization of fractional quantum Hall states, and indicate challenges and solutions for examining pumped, non-equilibrium systems that do not admit a mean-field description. Finally, potential applications of these ideas in passive and active photonics will be examined.

Taylor, Jacob

2013-03-01

48

Research in elementary particle physics  

SciTech Connect

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

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

1992-01-01

49

Particle Physics: The first axion?  

NASA Astrophysics Data System (ADS)

For almost 30 years, the hunt has been on for a ghostly particle proposed to plug a gap in the standard model of particle physics. The detection of a tiny optical effect might be the first positive sighting.

Lamoreaux, Steve

2006-05-01

50

Particle physics and astrophysics. Current viewpoints. Proceedings.  

NASA Astrophysics Data System (ADS)

The present conference discusses particle-physics concepts bearing on spontaneous symmetry breaking and novel particles from supersymmetry and supergravity, nucleon synthesis, baryon synthesis, universe inflation, bounds on axions from stellar evolution, the physics of type II supernova explosions, the physics of stellar collapse, and basic equations for gravitational collapse. Also discussed are the evidence for black holes, principles of black hole energetics, computer simulations prompted by quantum gravity requirements, neutrino oscillations and their damping, and the possibility of phase transitions serving as the origin of large-scale structure in the universe. Eight articles on the interactions between the ideas and concepts of particle physics and those of astrophysics make up this book. Two long introductory lectures give a survey of modern concepts in particle physics and in astrophysics and cosmology, stressing features of common interest. The other contributions deal with the physics of supernova explosions, with black holes, with neutrino oscillations, with the importance of phase transitions for the large-scale structure of the universe, and with the use of the ideas of quantum gravity for computer simulations.

Mitter, H.; Widder, F.

51

Sub-shot-noise quantum metrology with entangled identical particles  

SciTech Connect

The usual notion of separability has to be reconsidered when applied to states describing identical particles. A definition of separability not related to any a priori Hilbert space tensor product structure is needed: this can be given in terms of commuting subalgebras of observables. Accordingly, the results concerning the use of the quantum Fisher information in quantum metrology are generalized and physically reinterpreted.

Benatti, F. [Dipartimento di Fisica, Universita di Trieste, 34014 Trieste (Italy); Istituto Nazionale di Fisica Nucleare, Sezione di Trieste, 34014 Trieste (Italy)], E-mail: benatti@ts.infin.it; Floreanini, R. [Istituto Nazionale di Fisica Nucleare, Sezione di Trieste, 34014 Trieste (Italy); Marzolino, U. [Dipartimento di Fisica, Universita di Trieste, 34014 Trieste (Italy); Istituto Nazionale di Fisica Nucleare, Sezione di Trieste, 34014 Trieste (Italy)

2010-04-15

52

Research in elementary particle physics  

NASA Astrophysics Data System (ADS)

This report discusses the following topics: Low-energy particle dynamics; QCD dynamics on the lattice; lattice QCD Vacuum; phenomenology & cosmology; the ZEUS Experiment at HERA; neutrino physics at LAMPF; non-accelerator physics; and SSC activity.

Chan, Lai-Him; Haymaker, R.; Imlay, R.; McNeil, R.; Metcalf, W.; Svoboda, R.

53

Quantum Mechanics and Physical Reality  

Microsoft Academic Search

IN a recent article by A. Einstein, B. Podolsky and N. Rosen, which appeared in the Physical Review of May 15, and was reviewed in NATURE of June 22, the question of the completeness of quantum mechanical description has been discussed on the basis of a ``criterion of physical reality'', which the authors formulate as follows : ``If, without in

N. Bohr

1935-01-01

54

Testing Quantum Mechanics in High-Energy Physics  

Microsoft Academic Search

In this set of lectures we show that particle physics can also contribute to fundamental questions about quantum mechanics\\u000a (QM) and even shine new light in the fine workings of quantum physics and this at scales of energies which are not available\\u000a for usual quantum systems. In particular the massive meson–antimeson systems are specially suitable as they offer a unique

Beatrix C. Hiesmayr

55

Quantum information is physical  

Microsoft Academic Search

We discuss a few current developments in the use of quantum mechanically coherent systems for information processing. In each of these developments, Rolf Landauer has played a crucial role in nudging us, and other workers in the field, into asking the right questions, some of which we have been lucky enough to answer. A general overview of the key ideas

David P. DiVincenzo; Daniel Loss

1998-01-01

56

Higher-dimensional oscillations of quantum particles  

NASA Astrophysics Data System (ADS)

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.

Hedin, Eric

2013-04-01

57

Quantum structures, separated physical entities and probability  

Microsoft Academic Search

We prove that if the physical entity S consisting of two separated physical entities S1 and S2 satisfies the axioms of orthodox quantum mechanics, then at least one of the two subentities is a classical physical entity. This theorem implies that separated quantum entities cannot be described by quantum mechanics. We formulate this theorem in an approach where physical entities

Diederik Aerts

1994-01-01

58

Quantum simulations of physics problems  

SciTech Connect

If a large Quantum Computer (QC) existed today, what type of physical problems could we efficiently simulate on it that we could not efficiently 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, and we show quantum networks useful for the efficient evaluation of some physical properties, such as correlation functions and energy spectra.

Somma, R. D. (Rolando D.); Ortiz, G. (Gerardo); Knill, E. H. (Emanuel H.); Gubernatis, J. E.

2003-01-01

59

Interpretation of Quantum Physics  

Microsoft Academic Search

MR. STOPES-ROE sees a difficulty for the pure particle theory of diffraction in the assumption of `collective action' of the reacting body as a whole, be it a crystal, or a screen with slits, or I may add any measuring instrument. But this collective action is justified, and is always taken for granted in the non-relativistic theory where communication is

Alfred Landé

1962-01-01

60

Quantum Physics in One Dimension  

Microsoft Academic Search

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

David Logan

2004-01-01

61

Machines, logic and quantum physics  

Microsoft Academic Search

Though the truths of logic and pure mathematics are objective and independent of any contingent facts or laws of nature, our knowledge of these truths depends entirely on our knowledge of the laws of physics. Recent progress in the quantum theory of computation has provided practical instances of this, and forces us to abandon the classical view that computation, and

David Deutsch; Artur Ekert; Rossella Lupacchini

2000-01-01

62

Survey of general quantum physics  

Microsoft Academic Search

The abstract description of a physical system is developed, along lines originally suggested by Birkhoff and von Neumann, in terms of the complete lattice of propositions associated with that system, and the distinction between classical and quantum systems is made precise. With the help of the notion of state, a propositional system is defined: it is remarked that every irreducible

C. Piron

1972-01-01

63

QUANTUM PHYSICS, CONSCIOUSNESS AND LIFE  

Microsoft Academic Search

The paper analyses a model, based on quantum physics and Einstein's famous relation E = mc2, which tries to explain the connection between brain functioning and the consciousness manifestation. The model predicts the presence of a new human consciousness in the mother's body from the first weeks of pregnancy. The moral implications of these results and a Christian perspective on

Iulian Rusu; Alice Rusu

64

Niels Bohr and quantum physics  

Microsoft Academic Search

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

A B Migdal

1985-01-01

65

Quantum teleportation using three-particle entanglement  

Microsoft Academic Search

We investigate the ``teleportation'' of a quantum state using three-particle entanglement to either one of two receivers in such a way that, generally, either one of the two, but only one, can fully reconstruct the quantum state conditioned on the measurement outcome of the other. We furthermore delineate the similarities between this process and a quantum nondemolition measurement.

Anders Karlsson; Mohamed Bourennane

1998-01-01

66

Particle Identification for Beauty Physics.  

National Technical Information Service (NTIS)

We look briefly at the requirements for particle identification for possible beauty experiments at the Tevatron, both in the fixed target and the collider mode. Techniques presently in use in high energy physics experiments, and under development, should ...

T. Ludlam

1987-01-01

67

A novel quantum physics course for physics teachers: theoretical background  

Microsoft Academic Search

The aim of this cooperation project between Universities of Joensuu and Helsinki is to study the learning and teaching of quantum physics and to develop a new research-based quantum physics course for physics teachers. This way the new instructional models are hopefully spreading also to the lower educational levels. As physics educators have stated, physics is not considered very attractive

Mervi Asikainen; Pekka E. Hirvonen; Matti Heikkinen; Ville Nivalainen

68

Quantum flutter of supersonic particles in one-dimensional quantum liquids  

NASA Astrophysics Data System (ADS)

Fast obstacles in a medium are responsible for striking physical phenomena, such as aerodynamic flutter, ?erenkov radiation and acoustic shock waves. In a hydrodynamic picture, quantum systems exhibit analogues of these dynamical features. Here we uncover novel quantum dynamics induced by fast particles by considering impurities injected supersonically into a one-dimensional quantum liquid. We find that the injected particle never comes to a full stop, at odds with conventional expectations of relaxation. Furthermore the system excites a new type of collective mode, manifesting itself in several observable quantities, such as long-lived oscillations in the velocity of the injected particle and simultaneous oscillations of the correlation hole formed around the impurity. These features are inherently quantum-mechanical and provide an example of a dynamically formed quantum coherent state propagating through a many-body environment while maintaining its coherence. The signatures of these effects can be probed directly with existing experimental tools.

Mathy, Charles J. M.; Zvonarev, Mikhail B.; Demler, Eugene

2012-12-01

69

Recent developments in quantum plasma physics  

Microsoft Academic Search

We present a review of recent developments in nonlinear quantum plasma physics involving quantum hydrodynamics and effective nonlinear Schrödinger equation formalisms, for describing collective phenomena in dense quantum plasmas with degenerate electrons. As examples, we discuss simulation studies of the formation and dynamics of dark solitons and quantum vortices, and of nonlinear interactions between intense circularly polarized electromagnetic (CPEM) waves

P. K. Shukla; B. Eliasson

2010-01-01

70

Quantum fingerprinting with a single particle  

SciTech Connect

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

Massar, S. [Laboratoire d'Information Quantique and Centre for Quantum Information and Communication (QUIC), Universite Libre de Bruxelles, C.P. 165/59, Avenue F.D. Roosevelt 50, 1050 Brussels (Belgium)

2005-01-01

71

Space-QUEST: quantum physics and quantum communication in space  

NASA Astrophysics Data System (ADS)

Fundamental quantum optics test as well as quantum cryptography and quantum teleportation are based on the distribution of single quantum states and quantum entanglement respectively. We will discuss recent experimental achievements in the field of long-distance quantum communication via optical fiber as well as in free-space over a record breaking distance of 144 km. The European Space Agency (ESA) has supported a range of studies in the field of quantum physics and quantuminformation science in space for several years, and consequently a mission proposal Space-QUEST Quantum Entanglement for Space Experiments was submitted to the European Life and Physical Sciences in Space Program. This proposal envisions to perform space-to-ground quantum communication tests from the International Space Station (ISS) and will presented in this article.

Ursin, Rupert; Jennewein, Thomas; Zeilinger, Anton

2009-01-01

72

Quantum counting algorithm and its application in mesoscopic physics  

SciTech Connect

We discuss a quantum counting algorithm which transforms a physical particle-number state (and superpositions thereof) into a binary number. The algorithm involves two quantum Fourier transformations. One transformation is in physical space, where a stream of nparticles is coupled to K qubits, rotating their states by prescribed angles. The second transformation is within the Hilbert space of qubits and serves to read out the particle number in a binary form. Applications include a divisibility check characterizing the size of a finite train of particles in a quantum wire and a scheme allowing one to entangle multiparticle wave functions in a Mach-Zehnder interferometer, generating Bell, Greenberger-Horne-Zeilinger, or Dicke states.

Lesovik, G. B. [L. D. Landau Institute for Theoretical Physics RAS, 117940 Moscow (Russian Federation); Theoretische Physik, ETH-Zurich, CH-8093 Zuerich (Switzerland); Suslov, M. V. [Moscow Institute of Physics and Technology, Institutskii per. 9, 141700 Dolgoprudny, Moscow District (Russian Federation); NIX Computer Company, R and D Department, Zvezdniy Boulevard 19, 129085 Moscow (Russian Federation); Blatter, G. [Theoretische Physik, ETH-Zurich, CH-8093 Zuerich (Switzerland)

2010-07-15

73

Introduction to Elementary Particle Physics  

NASA Astrophysics Data System (ADS)

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

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

2009-04-01

74

Particle identification for beauty physics  

Microsoft Academic Search

We look briefly at the requirements for particle identification for possible beauty experiments at the Tevatron, both in the fixed target and the collider mode. Techniques presently in use in high energy physics experiments, and under development, should make sensitive experiments feasible. However, in all cases the present state of the art must be advanced to meet the necessary requirements

Ludlam

1987-01-01

75

Quantum optomechanics: exploring the interface between quantum physics and gravity  

NASA Astrophysics Data System (ADS)

Massive mechanical objects are now becoming available as new systems for quantum science. Quantum optics provides a powerful toolbox to generate, manipulate and detect quantum states of motion of such mechanical systems -- from nanomechanical waveguides of some picogram to macroscopic, kilogram-weight mirrors of gravitational wave detectors. Recent experiments, including laser-cooling of massive mechanical devices into their quantum ground state of motion, and demonstrations of the strong coupling regime provide the primary building blocks for full quantum optical control of mechanics, i.e. quantum optomechanics. This has fascinating perspectives for both applications and for quantum foundations: For example, the on-chip integrability of nano- and micromechanics, together with their flexibility to couple to different physical systems, offers a novel perspective for solid-state quantum information processing architectures. At the same time, the mass and size of mechanical resonators provides access to a hitherto untested parameter regime of macroscopic quantum physics via the generation of superposition states of massive systems and of optomechanical quantum entanglement, which is at the heart of Schr"odinger's cat paradox. Finally, and somewhat surprisingly, due to the large available masses it becomes even possible to explore the fascinating interface between quantum physics and (quantum) gravity in table-top quantum optics experiments. I will discuss a few examples.

Aspelmeyer, Markus

2012-06-01

76

Critique of ``Quantum Enigma: Physics Encounters Consciousness''  

NASA Astrophysics Data System (ADS)

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.

Nauenberg, Michael

2007-11-01

77

Quantum cascade lasers in chemical physics  

Microsoft Academic Search

In the short space of 15years since their first demonstration, quantum cascade lasers have become the most useful sources of tunable mid-infrared laser radiation. This Letter describes these developments in laser technology and the burgeoning applications of quantum cascade lasers to infrared spectroscopy. We foresee the potential application of quantum cascade lasers in other areas of chemical physics such as

Robert F. Curl; Federico Capasso; Claire Gmachl; Anatoliy A. Kosterev; Barry McManus; Rafal Lewicki; Michael Pusharsky; Gerard Wysocki; Frank K. Tittel

2010-01-01

78

Cosmic Inflation Meets Particle Physics  

NASA Astrophysics Data System (ADS)

While there exists a large multitude of inflationary models, the connection of inflation to particle physics is still an unsolved puzzle. In particular, in supergravity theories, where the so-called ?-problem tends to spoil slow-roll inflation, the construction of convincing and technically natural models of inflation is challenging. We discuss some recent developments regarding the quest for particle physics models of inflation in supergravity. One such development is provided by a new class of inflationary models, referred to as "tribrid inflation", which is taylor-made for solving the ?-problem by shift symmetry or Heisenberg symmetry. Based on this approach, it has recently been shown that inflation can be consistently realised with a gauge non-singlet inflaton field (residing e.g. in a GUT representation), with, simultaneously, the ?-problem solved by a Heisenberg symmetry.

Antusch, S.; Baumann, J. P.; Dutta, K.; Kostka, P. M.

2011-03-01

79

Supersymmetry in Elementary Particle Physics  

SciTech Connect

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.

Peskin, Michael E.; /SLAC

2008-02-05

80

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

SciTech Connect

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

Not Available

1992-09-01

81

Quantum Security for the Physical Layer  

SciTech Connect

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.

Humble, Travis S [ORNL

2013-01-01

82

Quantum information and physics: some future directions  

Microsoft Academic Search

I consider some promising future directions for quantum information theory that could influence the development of 21st century physics. Advances in the theory of the distinguishability of superoperators may lead to new strategies for improving the precision of quantum-limited measurements. A better grasp of the properties of multi-partite quantum entanglement may lead to deeper understanding of strongly-coupled dynamics in quantum

John Preskill

2000-01-01

83

An Inverse Problem in Quantum Statistical Physics  

Microsoft Academic Search

We address the following inverse problem in quantum statistical physics: does the quantum free energy (von Neumann entropy\\u000a + kinetic energy) admit a unique minimizer among the density operators having a given local density n(x)? We give a positive answer to that question, in dimension one. This enables to define rigourously the notion of local quantum\\u000a equilibrium, or quantum Maxwellian, which

Florian Méhats; Olivier Pinaud

2010-01-01

84

Introduction to Quantum Sensors in Cryogenic Particle Detection  

NASA Astrophysics Data System (ADS)

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

Kim, Yong-Hamb; Kim, Sun Kee

85

The Physical Implementation of Quantum Computation  

Microsoft Academic Search

After a brief introduction to the principles and promise of quantum\\u000ainformation processing, the requirements for the physical implementation of\\u000aquantum computation are discussed. These five requirements, plus two relating\\u000ato the communication of quantum information, are extensively explored and\\u000arelated to the many schemes in atomic physics, quantum optics, nuclear and\\u000aelectron magnetic resonance spectroscopy, superconducting electronics, and\\u000aquantum-dot

David P. DiVincenzo

2000-01-01

86

Teaching Elementary Particle Physics: Part I1  

NASA Astrophysics Data System (ADS)

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

Hobson, Art

2011-01-01

87

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

ERIC Educational Resources Information Center

|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.…

Pujol, O.; Perez, J. P.

2007-01-01

88

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

Microsoft Academic Search

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

O. Pujol; J. P. Pérez

2007-01-01

89

GPUs in experimental particle physics  

NASA Astrophysics Data System (ADS)

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

Berger, Niklaus

2012-03-01

90

Quantum particle production at sudden singularities  

SciTech Connect

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.

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

91

Non-accelerator particle physics  

SciTech Connect

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.

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

1991-09-01

92

Unstable particles in non-relativistic quantum mechanics?  

SciTech Connect

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

Hernandez-Coronado, H. [Instituto Mexicano del Petroleo, Eje central Lazaro Cardenas 152, 07730, Mexico D.F. (Mexico)

2011-10-14

93

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

SciTech Connect

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)

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

1992-05-01

94

Quantum Theory of Unstable Particles and Relativity.  

National Technical Information Service (NTIS)

A new phenomena on the connection between Quantum Theory of unstable elementary particles and Relativity were derived. A new form of the beta spectrum without 'end-point' in the nuclear radioactive decay was predicted, different from the usually used in t...

L. A. Khalfin

1997-01-01

95

Quantum brownian particle and memory effects.  

National Technical Information Service (NTIS)

The Quantum Brownian particle, immersed in a heat bath, is described by a statistical operator whose evolution is ruled by a Generalized Master Equation (GME). The heat bath degrees of freedom are considered to be either white noise or coloured noise corr...

J. R. Britani S. S. Mizrahi B. M. Pimentel

1991-01-01

96

Particles and Fields: Classical and Quantum  

Microsoft Academic Search

This volume contains some of the contributions to the Conference Particles and Fields: Classical and Quantum, which was held at Jaca (Spain) in September 2006 to honour George Sudarshan on his 75th birthday. Former and current students, associates and friends came to Jaca to share a few wonderful days with George and his family and to present some contributions of

M Asorey; J Clemente-Gallardo; G Marmo

2007-01-01

97

The physical renormalization of quantum field theories  

NASA Astrophysics Data System (ADS)

The profound revolutions in particle physics likely to emerge from current and future experiments motivates an improved understanding of the precise predictions of the Standard Model and new physics models. Higher order predictions in quantum field theories inevitably requires the renormalization procedure, which makes sensible predictions out of the naively divergent results of perturbation theory. Thus, a robust understanding of renormalization is crucial for identifying and interpreting the possible discovery of new physics. The results of this thesis represent a broad set of investigations into the nature of renormalization. I begin by motivating a more physical approach to renormalization based on gauge-invariant Green's functions. The resulting effective charges are first applied to gauge coupling unification. This approach provides an elegant formalism for understanding all threshold corrections, and the gauge couplings unify in a more physical manner compared to the usual methods. Next, the gauge-invariant three-gluon vertex is studied in detail, revealing an interesting and rich structure. The effective coupling for the three-gluon vertex, ak21,k2 2,k23 , depends on three momentum scales and gives rise to an effective scale Q2effk21 ,k22,k23 which governs the (sometimes surprising) behavior of the vertex. The effects of nonzero internal masses are important and have a complicated threshold and pseudo-threshold structure. The pinch-technique effective charge is also calculated to two-loops and several applications are discussed. The Higgs boson mass in Split Supersymmetry is calculated to two-loops, including all one-loop threshold effects, leading to a downward shift in the Higgs mass of a few GeV. Finally, I discuss some ideas regarding the overall structure of perturbation theory. This thesis lays the foundation for a comprehensive multi-scale analytic renormalization scheme based on gauge-invariant Green's functions, in which the scale ambiguity problem is reduced since physical kinematic invariants determine the arguments of the couplings.

Binger, Michael William

98

Quantum physics of molecular magnets  

NASA Astrophysics Data System (ADS)

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

Jaafar, Reem

99

Quantum formulation of plasma physics  

NASA Astrophysics Data System (ADS)

I formulate plasma physics according to postulates of quantum mechanics, base on electron number density. List of Plasma Quantity: n_e={dN}/{dV} electron number density. j=n_e.u electron number current density where the u denotes velocity. H_v={j^2}/{2n_e}+U_v=E_v This is Number Hamiltonian density where the U_v denotes Number potential energy density and E_v denotes Number total energy density. R_m Magnetic Reynolds Number. k_m={R_m}/{L} Magnetic reynolds wave number. ?_m magnetic wave function. ?=n_e.? dynamic magnetic diffusivity where the ? denotes magnetic diffusivity. Essential Relations: j=? .k_ m=n_e.u and then, nabla^2?_m+k_m^2?_m=0 where the nabla^2 is laplacian operator. {-?^2nabla^2?_m}/{(1+?)n_e}+U_v?_m=E_v ?_m this is my equation of plasma that appears to be an relativistic expression of schrodinger equation, where the ? denotes lorentz factor and at l! ow speeds ?+1=2 and so on...etc.

Estakhr, Ahmad Reza

2013-06-01

100

Quantum Interpretations in Modern Physics Instruction  

NSDL National Science Digital Library

Just as expert physicists vary in their personal stances on interpretation in quantum mechanics, instructors hold different views on teaching interpretations of quantum phenomena in introductory modern physics courses. There has been relatively little research in the physics education community on the variation in instructional approaches with respect to quantum interpretation, and how instructional choices impact student thinking. We compare two modern physics courses taught at the University of Colorado with similar learning environments, but where the instructors held different views on how to teach students about interpretations of quantum processes. We find significant differences in how students from these two courses responded to a survey on their beliefs about quantum mechanics; findings also suggest that instructors who choose to address student ontologies should do so across a range of topics.

Baily, Charles; Finkelstein, Noah D.

2010-01-19

101

Quantum Interpretations in Modern Physics Instruction  

NASA Astrophysics Data System (ADS)

Just as expert physicists vary in their personal stances on interpretation in quantum mechanics, instructors hold different views on teaching interpretations of quantum phenomena in introductory modern physics courses. There has been relatively little research in the physics education community on the variation in instructional approaches with respect to quantum interpretation, and how instructional choices impact student thinking. We compare two modern physics courses taught at the University of Colorado with similar learning environments, but where the instructors held different views on how to teach students about interpretations of quantum processes. We find significant differences in how students from these two courses responded to a survey on their beliefs about quantum mechanics; findings also suggest that instructors who choose to address student ontologies should do so across a range of topics.

Baily, Charles; Finkelstein, Noah D.

2009-11-01

102

On the ‘Emptiness’ of Particles in Condensed-matter Physics  

Microsoft Academic Search

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

L. Q. English

2007-01-01

103

Meaning of counterfactual statements in quantum physics  

Microsoft Academic Search

David Mermin suggests that my recent proof pertaining to quantum nonlocality is undermined by an essential ambiguity pertaining to the meaning of counterfactual statements in quantum physics. The ambiguity he cites arises from his imposition of a certain criterion for the meaningfulness of such counterfactual statements. That criterion conflates the meaning of a counterfactual statement with the details of a

Henry P. Stapp

1998-01-01

104

Experiment and the foundations of quantum physics  

Microsoft Academic Search

Instead of having to rely on gedanken (thought) experiments, it is possible to base this discussion of the foundations of quantum physics on actually performed experiments because of the enormous experimental progress in recent years. For reasons of space, the author discusses mainly experiments related to the Einstein-Podolsky-Rosen paradox and Bell's theorem, that is, to quantum entanglement. Not only have

Anton Zeilinger

1999-01-01

105

The dialogue between particle physics and cosmology  

SciTech Connect

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

Sadoulet, B.

1988-04-01

106

Particle identification for beauty physics  

SciTech Connect

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

Ludlam, T.

1987-01-01

107

Particle Physics on the Eve of Lhc  

NASA Astrophysics Data System (ADS)

Fundamentals of particle physics. The quantum number of color, colored quarks and dynamic models of Hadrons composed of quasifree quarks / V. Matveev, A. Tavkhelidze. Discovery of the color degree of freedom in particle physics: a personal perspective / O. W. Greenberg. The evolution of the concepts of energy, momentum, and mass from Newton and Lomonosov to Einstein and Feynman / L. Okun -- Physics at accelerators and studies in SM and beyond. Search for new physics at LHC (CMS) / N. Krasnikov. Measuring the Higgs Boson(s) at ATLAS / C. Kourkoumelis. Beyond the standard model physics reach of the ATLAS experiment / G. Unel. The status of the International Linear Collider / B. Foster. Review of results of the electron-proton collider HERA / V. Chekelian. Recent results from the Tevatron on CKM matrix elements from Bs oscillations and single top production, and studies of CP violation in Bs Decays / J. P. Fernández. Direct observation of the strange b Barion [symbol] / L. Vertogradov. Search for new physics in rare B Decays at LHCb / V. Egorychev. CKM angle measurements at LHCb / S. Barsuk. Collider searches for extra spatial dimensions and black holes / G. Landsberg -- Neutrino Physics. Results of the MiniBooNE neutrino oscillation experiment / Z. Djurcic. MINOS results and prospects / J. P. Ochoa-Ricoux. The new result of the neutrino magnetic moment measurement in the GEMMA experiment / A. G. Beda ... [et al.]. The Baikal neutrino experiment: status, selected physics results, and perspectives / V. Aynutdinov ... [et al.]. Neutrino telescopes in the deep sea / V. Flaminio. Double beta decay: present status / A. S. Barabash. Beta-beams / C. Volpe. T2K experiment / K. Sakashita. Non-standard neutrino physics probed by Tokai-to-Kamioka-Korea two-detector complex / N. Cipriano Ribeiro ... [et al.]. Sterile neutrinos: from cosmology to the LHC / F. Vannucci. From Cuoricino to Cuore towards the inverted hierarchy region / C. Nones. The MARE experiment: calorimetric approach to the direct measurement of the neutrino mass / E. Andreotti. Electron angular correlation in neutrinoless double beta decay and new physics / A. Ali, A. Borisov, D. Zhuridov. Neutrino energy quantization in rotating medium / A. Grigoriev, A. Studenikin. Neutrino propagation in dense magnetized matter / E. V. Arbuzova, A. E. Lobanov, E. M. Murchikova. Plasma induced neutrino spin flip via the neutrino magnetic moment / A. Kuznetsov, N. Mikheev -- Astroparticle physics and cosmology. International Russian-Italian mission "RIM-PAMELA" / A. M. Galper .. [et al.]. Dark Matter searches with AMS-02 experiment / A. Malinin. Investigating the dark halo / R. Bernabei ... [et al.]. Search for rare processes at Gran Sasso / P. Belli ... [et al.]. Anisotropy of Dark Matter annihilation and remnants of Dark Matter clumps in the galaxy / V. Berezinsky, V. Dokuchaev, Yu. Eroshenko. Current observational constraints on inflationary models / E. Mikheeva. Phase transitions in dense quark matter in a constant curvature gravitational field / D. Ebert, V. Ch. Zhukovsky, A. V. Tyukov. Construction of exact solutions in two-fields models / S. Yu. Vernov. Quantum systems bound by gravity / M. L. Fil'chenkov, S. V. Kopylov, Y. P. Laptev -- CP violation and rare decays. Some puzzles of rare B-Decays / A. B. Kaidalov. Measurements of CP violation in b decays and CKM parameters / J. Chauveau. Evidence for D[symbol] mixing at BaBar / M. V. Purohit. Search for direct CP violation in charged kaon decays from NA48/2 experiment / S. Balev. [symbol] scattering lengths from measurements of K[symbol] and K± -> [symbol] decays at NA48/2 / D. Madigozhin. Rare kaon and hyperon decays in NA48 experiment / N. Molokanova. THE K+ -> [symbol]+vv¯ experiment at CERN / Yu. Potrebenikov. Recent KLOE results / B. Di Micco.Decay constants and masses of heavy-light mesons in field correlator method / A. M. Badalian. Bilinear R-parity violation in rare meson decays / A. Ali, A. V. Borisov, M. V. Sidorova. Final state interaction in K -> 2[symbol] decay / E. Shabalin -- Hadron physi

Studenikin, Alexander I.

2009-01-01

108

Novel quantum numbers in condensed matter physics  

Microsoft Academic Search

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

J. R. Schrieffer

2004-01-01

109

Statistical problems in quantum physics  

Microsoft Academic Search

In this paper, we give a general and unified mathematical treatment for a number of statistical problems concerning optimal quantum measurements. It has at least one field of application, namely, the theory of quantum communication channels and optimal receivers of optical signals [I] . Of course, if we are concerned with the data already obtained by a given measurement, then

A. S. Holevo

110

Quantum effects in accelerator physics.  

National Technical Information Service (NTIS)

Quantum effects for electrons in a storage ring are discussed, in particular the polarization effect due to spin flip synchrotron radiation. The electrons are treated as a simple quantum mechnical two-level system coupled to the orbital motion and the rad...

J. M. Leinaas

1991-01-01

111

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

Microsoft Academic Search

A variety of physical phenomena have at their foundation the quantum tunneling of particles through potential barriers. Many of these phenomena can be associated with the tunneling of single inert particles. The tunneling of composite systems is more complex than for single particles due to the coupling of the tunneling coordinate with the internal degrees of freedom of the tunneling

A. C. Shotter; M. D. Shotter

2011-01-01

112

Some inner physical properties of material particles  

Microsoft Academic Search

It is shown that the Maxwell equations, which usually apply only outside material particles, apply also inside, giving standing or trapped wave solutions, both for electromagnetic field and for charge and current densities. The quantum mechanical function and the amplitude u-function apply inside and outside particles.

Claude Elbaz

1987-01-01

113

Research in elementary particle physics  

SciTech Connect

This paper discusses: CDF analysis; CDF system support; SSC laboratory development; solenoidal detector collaboration program; meson spectroscopy; conformal field theory; wormholes in quantum gravity; neural networks. (FI)

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

1990-01-01

114

Quantum Many Particle Systems in Ring-Shaped Optical Lattices  

SciTech Connect

In the present work we demonstrate how to realize a 1D closed optical lattice experimentally, including a tunable boundary phase twist. The latter may induce ''persistent currents,'' visible by studying the atoms' momentum distribution. We show how important phenomena in 1D physics can be studied by physical realization of systems of trapped atoms in ring-shaped optical lattices. A mixture of bosonic and/or fermionic atoms can be loaded into the lattice, realizing a generic quantum system of many interacting particles.

Amico, Luigi [CRS MATIS-INFM, via S. Sofia 64, 95125 Catania (Italy); Dipartimento di Metodologie Fisiche e Chimiche (DMFCI), Universita di Catania, viale A. Doria 6, 95125 Catania (Italy); Osterloh, Andreas [CRS MATIS-INFM, via S. Sofia 64, 95125 Catania (Italy); Institut fuer Theoretische Physik, Universitaet Hannover, 30167 Hannover (Germany); Cataliotti, Francesco [CRS MATIS-INFM, via S. Sofia 64, 95125 Catania (Italy); LNS-INFN Dipartimento di Fisica Scuola Superiore di Catania, Universita di Catania, via S. Sofia 64, 95125 Catania (Italy)

2005-08-05

115

Quantum Algorithms: Applicable Algebra and Quantum Physics  

Microsoft Academic Search

Classical computer science relies on the concept of Turing machines as a unifying model of universal computation. According\\u000a to the modern Church-Turing Thesis, this concept is interpreted in the form that every physically reasonable model of computation\\u000a can be efficiently simulated on a probabilistic Turing machine. Recently this understanding, which was taken for granted for a long time, has\\u000a required

Thomas Beth; Martin Roetteler

2001-01-01

116

Statistical particle tracking velocimetry using molecular and quantum dot tracer particles  

NASA Astrophysics Data System (ADS)

We present a statistical approach to particle tracking velocimetry developed to treat the issues associated with nanometer-sized tracer particles such as fluorescent molecules and quantum dots (QDs) along with theory and experimental results. Extremely small tracers pose problems to traditional tracking methods due to high levels of thermal motion, high levels of intensified camera noise, high drop-in/drop-out rates and, in the case of QDs, fluorescence intermittency (“blinking”). The algorithm presented here compensates for these problems in a statistical manner and determines the physical velocity distributions from measured particle displacement distributions by statistically removing randomly distributed, non-physical tracking events. The algorithm is verified with both numerically simulated particle trackings and experiments using 54 nm diameter fluorescent dextran molecules and 6 and 16 nm diameter QDs.

Guasto, Jeffrey S.; Huang, Peter; Breuer, Kenneth S.

2006-12-01

117

Addressing Student Models of Energy Loss in Quantum Physics  

NSDL National Science Digital Library

We report on a multi-year, multi-institution study to investigate students' reasoning about energy in the context of quantum tunnelling. We use ungraded surveys, graded examination questions, individual clinical interviews and multiple-choice exams to build a picture of the types of responses that students typically give. We find that two descriptions of tunnelling through a square barrier are particularly common. Students often state that tunnelling particles lose energy while tunnelling. When sketching wavefunctions, students also show a shift in the axis of oscillation, as if the height of the axis of oscillation indicated the energy of the particle. We find inconsistencies between students' conceptual, mathematical and graphical models of quantum tunnelling. As part of a curriculum in quantum physics, we have developed instructional materials designed to help students develop a more robust and less inconsistent picture of tunnelling, and present data suggesting that we have succeeded in doing so.

Wittmann, Michael C.; Morgan, Jeffrey; Bao, Lei

2013-05-28

118

Development of quantum perspectives in modern physics  

NSDL National Science Digital Library

Summary: Variations in student epistemic and ontological commitments can be characterized, and many students have preferences for realist interpretations of quantum phenomena. Abstract: 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.

Baily, Charles; Finkelstein, Noah D.

2012-01-20

119

Computer Visualization of Many-Particle Quantum Dynamics  

SciTech Connect

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

Ozhigov, A. Y. [Moscow State Institute of Electronics and Mathematics (Russian Federation)

2009-03-10

120

The Physical Renormalization of Quantum Field Theories  

SciTech Connect

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

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

2007-02-20

121

Particle Physics: From School to University.  

ERIC Educational Resources Information Center

|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)|

Barlow, Roger

1992-01-01

122

Towards Open Access Publishing in Particle Physics  

NASA Astrophysics Data System (ADS)

This paper, presented on behalf of the Sponsoring Consortium for Open Access Publishing in Particle Physics (SCOAP3) Working Party is extracted from a report available online (http://cern.ch/oa/Scoap3WPReport.pdf). It introduces the Open Access concept and presents the strategy plus timeline proposed by the Consortium in the field of particle physics.

Plaszczynski, Stéphane

123

Quarked!--Adventures in Particle Physics Education  

ERIC Educational Resources Information Center

|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…

MacDonald, Teresa; Bean, Alice

2009-01-01

124

Quantum dots: Paradigm changes in semiconductor physics  

Microsoft Academic Search

Deposition of one or a few monolayers of a semiconductor having a lattice constant largely different from the underlying substrate\\u000a leads to formation of coherent “quantum dot arrays” of densities beyond 1011 cm?2 in a matter of seconds. Self-organization effects govern their massively parallel formation. Fundamental paradigms of semiconductor\\u000a physics must be changed in describing such quantum dots or their

D. Bimberg

1999-01-01

125

Field Theoretic Investigations on Particle Physics and Cosmology. Annual Technical Progress Report.  

National Technical Information Service (NTIS)

Topics covered include topics bridging particle physics and cosmology, superconducting universe, inflationary universe, density fluctuations in the new inflationary universe, a realistic inflationary model, and the quantum mechanics of the scalar field in...

S. Y. Pi

1985-01-01

126

Topics in elementary particle physics  

NASA Astrophysics Data System (ADS)

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

Jin, Xiang

127

Quantum Physics Online: Spin 1/2  

NSDL National Science Digital Library

This is a set of interactive Java applets illustrating the properties of quantum spin. Shown is a representation of states as an arrow in the average spin direction, as well as the expansion of the states in eigenstates of Sz. Simulations show the dynamics of spin states in static, rotating, and pulsed magnetic fields. These applets are part of an extensive collection of animations and simulations illustrating a large range of quantum topics, and an ongoing effort for developing a fully interactive quantum-physics class. Both French and English versions are available.

Joffre, Manuel

2004-03-28

128

Quantum Physics Online: Quantization in one dimension  

NSDL National Science Digital Library

This is a set of interactive Java applets illustrating one-dimensional quantum states. Simulations are used to illustrate both free and bound states, and the formation of eigenstates in one-dimensional potential wells. There are also illustrations of expanding states in a basis of harmonic oscillator states. These applets are part of an extensive collection of animations and simulations illustrating a large range of quantum topics, and an ongoing effort for developing a fully interactive quantum-physics class. Both French and English versions are available.

Joffre, Manuel

2004-03-28

129

Atoms, Molecules and Photons: An Introduction to Atomic Molecular and Quantum Physics  

Microsoft Academic Search

This introduction to Atomic and Molecular Physics explains how our present model of atoms and molecules has been developed during the last two centuries by many experimental discoveries and from the theoretical side by the introduction of quantum physics to the adequate description of micro-particles. It illustrates the wave model of particles by many examples and shows the limits of

Wolfgang Demtröder

2006-01-01

130

Plato's TIMAIOsigma (TIMAEUS) and Modern Particle Physics  

Microsoft Academic Search

It is generally known that the question, ``What are the smallest particles (elementary particles) that all matter is made from?'', was posed already in the antiquity. The Greek natural philosophers Leucippus and Democritus were the first to suggest that all matter was made from atoms. Therefore, most people perceive them as the ancient fathers of elementary particle physics. It will

Ruprecht Machleidt

2005-01-01

131

Development of quantum perspectives in modern physics  

NASA Astrophysics Data System (ADS)

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.

Baily, Charles; Finkelstein, Noah D.

2009-06-01

132

Differential evolution for many-particle adaptive quantum metrology.  

PubMed

We devise powerful algorithms based on differential evolution for adaptive many-particle quantum metrology. Our new approach delivers adaptive quantum metrology policies for feedback control that are orders-of-magnitude more efficient and surpass the few-dozen-particle limitation arising in methods based on particle-swarm optimization. We apply our method to the binary-decision-tree model for quantum-enhanced phase estimation as well as to a new problem: a decision tree for adaptive estimation of the unknown bias of a quantum coin in a quantum walk and show how this latter case can be realized experimentally. PMID:23767703

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

2013-05-28

133

Differential Evolution for Many-Particle Adaptive Quantum Metrology  

NASA Astrophysics Data System (ADS)

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

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

2013-05-01

134

Thermal equilibrium of two quantum Brownian particles  

SciTech Connect

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.

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

135

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

ERIC Educational Resources Information Center

|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.…

Ellison, Mark D.

2008-01-01

136

Recent developments in quantum plasma physics  

NASA Astrophysics Data System (ADS)

We present a review of recent developments in nonlinear quantum plasma physics involving quantum hydrodynamics and effective nonlinear Schrödinger equation formalisms, for describing collective phenomena in dense quantum plasmas with degenerate electrons. As examples, we discuss simulation studies of the formation and dynamics of dark solitons and quantum vortices, and of nonlinear interactions between intense circularly polarized electromagnetic (CPEM) waves and electron plasma oscillations (EPOs) in dense quantum-electron plasmas with immobile ions. The electron dynamics of dark solitons and quantum vortices is governed by a pair of equations comprising the nonlinear Schrödinger and Poisson system of equations. Both dark solitons and singly charged electron vortices are robust, and the latter tend to form pairs of oppositely charged vortices. The two-dimensional quantum-electron vortex pairs survive during collisions under the change of partners. The dynamics of the CPEM waves is governed by a nonlinear Schrödinger equation, which is nonlinearly coupled with the Schrödinger equation of the EPOs via the relativistic ponderomotive force, the relativistic electron mass increase in the CPEM field, and the electron density fluctuations. The present governing equations in one-spatial dimension admit stationary solutions in the form of dark solitons. The nonlinear equations also depict trapping of localized CPEM wave envelopes in the electron density holes that are associated with a positive potential profile.

Shukla, P. K.; Eliasson, B.

2010-12-01

137

Frontiers of particle beam physics.  

National Technical Information Service (NTIS)

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 ...

A. M. Sessler

1989-01-01

138

Finite quantum physics and noncommutative geometry  

Microsoft Academic Search

Conventional discrete approximations of a manifold do not preserve its\\u000anontrivial topological features. In this article we describe an approximation\\u000ascheme due to Sorkin which reproduces physically important aspects of manifold\\u000atopology with striking fidelity. The approximating topological spaces in this\\u000ascheme are partially ordered sets (posets). Now, in ordinary quantum physics on\\u000aa manifold $M$, continuous probability densities generate

A. P. Balachandran; G. Bimonte; E. Ercolessi; G. Landi; F. Lizzi; G. Sparano; P. Teotoniosobrinho

1995-01-01

139

BOOK REVIEW: Quantum Physics in One Dimension  

Microsoft Academic Search

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

T. Giamarchi

2004-01-01

140

Quantum Field Theory in Condensed Matter Physics  

Microsoft Academic Search

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

Alexei M. Tsvelik

2003-01-01

141

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

Microsoft Academic Search

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

Hiroomi Umezawa

1984-01-01

142

Popular and unpopular ideas in particle physics  

SciTech Connect

As particle physics becomes a deeper but more difficult field, there is too much emphasis on fashionable ideas and the search for anomalies, and too little reward for improving accelerators and detectors.

Perl, M.L.

1986-12-01

143

Medium energy elementary particle physics  

SciTech Connect

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

Not Available

1991-01-01

144

Interpretation in Quantum Physics as Hidden Curriculum  

NSDL National Science Digital Library

Prior research has demonstrated how the realist perspectives of classical physics students can translate into specific beliefs about quantum phenomena when taking an introductory modern physics course. Student beliefs regarding the interpretation of quantum mechanics often vary by context, and are most often in alignment with instructional goals in topic areas where instructors are explicit in promoting a particular perspective. Moreover, students are more likely to maintain realist perspectives in topic areas where instructors are less explicit in addressing interpretive themes, thereby making such issues part of a hidden curriculum. We discuss various approaches to addressing student perspectives and interpretive themes in a modern physics course, and explore the associated impacts on student thinking.

Baily, Charles; Finkelstein, Noah D.

2011-01-01

145

Theoretical particle physics. Progress report, FY 1993  

SciTech Connect

This report discusses the following topics: Heavy Quark Physics; Chiral Perturbation Theory; Skyrmions; Large-N Limit; Weak Scale Baryogenesis; Supersymmetry; Rare Decays; Technicolor; Chiral Lattice Fermions; Pauli-Villars Regulator and the Higgs Mass Bound; Higgs and Yukawa Interactions; Gauge Fixing; and Quantum Beables.

Not Available

1993-09-30

146

Atomic physics tests of nonlinear quantum mechanics  

NASA Astrophysics Data System (ADS)

Atomic physics experiments which test a nonlinear generalization of quantum mechanics recently formulated by Weinberg are described. The experiments search for a dependence of hyperfine transition frequencies or nuclear spin precession frequencies on the relative populations of the hyperfine or nuclear spin states. The experiments set limits less than 10 ?Hz on the size of the possible nonlinear contributions to these frequencies. In some cases this can be interpreted as a limit of less than ~10-26 on the fraction of binding energy per nucleon that could be due to a nonlinear correction to a nuclear Hamiltonian. The possibility that a nonlinear addition to quantum mechanics violates causality is discussed.

Bollinger, J. J.; Heinzen, D. J.; Itano, Wayne M.; Gilbert, S. L.; Wineland, D. J.

1991-08-01

147

Dirac particle in a box, and relativistic quantum Zeno dynamics  

Microsoft Academic Search

After developing a complete set of eigenfunctions for a Dirac particle restricted to a box, the quantum Zeno dynamics of a relativistic system is considered. The evolution of a continuously observed quantum mechanical system is governed by the theorem put forth by Misra and Sudarshan. One of the conditions for quantum Zeno dynamics to be manifest is that the Hamiltonian

Govind Menon; Sergey Belyi

2004-01-01

148

Nuclear physics with strange particles  

SciTech Connect

Recent progress in the understanding of strange particle interactions with nuclear systems is reviewed. We discuss the relative merits of various reactions such as (K/sup -/, ..pi../sup +-/), (..pi../sup +/, K/sup +/), or (..gamma.., K/sup +/) for hypernuclear production. The structure of /sub ..lambda..//sup 13/C is analyzed in some detail, in order to illustrate the role of the ..lambda..N residual interaction and approximate dynamical symmetries in hypernuclear structure. Recent results on the single particle states of a ..lambda.. in heavy systems, as revealed by (..pi../sup +/, K/sup +/) reaction studies, are used to extract information on the density dependence and effective mass which characterize the ..lambda..-nucleus mean field. Finally, we develop the idea the K/sup +/-nucleus scattering at low energies is sensitive to the subtle ''swelling'' effects for nucleons bound in nuclei. 64 refs., 13 figs.

Dover, C.B.

1988-01-01

149

Quantum Particles from Classical Probabilities in Phase Space  

NASA Astrophysics Data System (ADS)

Quantum particles in a potential are described by classical statistical probabilities. We formulate a basic time evolution law for the probability distribution of classical position and momentum such that all known quantum phenomena follow, including interference or tunneling. The appropriate quantum observables for position and momentum contain a statistical part which reflects the roughness of the probability distribution. "Zwitters" realize a continuous interpolation between quantum and classical particles. Such objects may provide for an effective one-particle description of classical or quantum collective states as droplets of a liquid, macromolecules or a Bose-Einstein condensate. They may also be used for quantitative fundamental tests of quantum mechanics. We show that the ground state for zwitters has no longer a sharp energy. This feature permits to put quantitative experimental bounds on a small parameter for possible deviations from quantum mechanics.

Wetterich, C.

2012-10-01

150

Quantum particles from coarse grained classical probabilities in phase space  

SciTech Connect

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

Wetterich, C., E-mail: c.wetterich@thphys.uni-heidelberg.d [Institut fuer Theoretische Physik, Universitaet Heidelberg, Philosophenweg 16, D-69120 Heidelberg (Germany)

2010-07-15

151

A quantum particle in a box with moving walls  

NASA Astrophysics Data System (ADS)

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

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

2013-09-01

152

Light particles A window to fundamental physics  

SciTech Connect

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.

Jaeckel, Joerg [Institute for Particle Physics Phenomenology, Durham University, Durham DH1 3LE (United Kingdom)

2010-08-30

153

PREFACE: Particles and Fields: Classical and Quantum  

NASA Astrophysics Data System (ADS)

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

International Advisory Committee

A. Ashtekhar (Pennsylvania State University, USA)
L. J. Boya (Universidad de Zaragoza, Spain)
I. Cirac (Max Planck Institute, Garching, Germany)
G. F. Dell Antonio (Universitá di Roma La Sapienza, Italy)
A. Galindo (Universidad Complutense de Madrid, Spain)
S. L. Glashow (Boston University, USA)
A. M. Gleeson (University of Texas, Austin, USA)
C. R. Hagen (Rochester University, NY, USA)
J. Klauder (University of Florida, Gainesville, USA)
A. Kossakowski (University of Torun, Poland)
V.I. Manko (Lebedev Physical Institute, Moscow, Russia)
G. Marmo (Universitá Federico II di Napoli e INFN Sezione di Napoli, Italy)
N. Mukunda (Indian Institute of Science, Bangalore, India)
J. V. Narlikar (Inter-University Centre for Astronomy and Astrophysics, Pune, India)
J. Nilsson (University of Goteborg, Sweden)
S. Okubo (Rochester University, NY, USA)
T. Regge (Politecnico di Torino, Italy)
W. Schleich (University of Ulm, Germany)
M. Scully (Texas A& M University, USA)
S. Weinberg (University of Texas, Austin, USA)

Local Organizing Committee

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

2007-07-01

154

Master Equation for a Quantum Particle in a Gas  

SciTech Connect

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.

Hornberger, Klaus [Arnold Sommerfeld Center for Theoretical Physics, Ludwig-Maximilians-Universitaet Muenchen, Theresienstrasse 37, 80333 Munich (Germany)

2006-08-11

155

Compact Stars. Nuclear Physics, Particle Physics and General Relativity.  

NASA Astrophysics Data System (ADS)

Neutron stars are the smallest denses stars known, with densities some 1014 times that of the Earth. They rotate with periods of fractions of a second, and their magnetic fields drive intense interstellar dynamos, lighting up entire nebulae. This text discusses the physics of these extreme objects. It includes the needed background in classical general relativity in nuclear and particle physics.

Glendenning, Norman

156

Elementary particle physics at the University of Florida  

SciTech Connect

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

Not Available

1991-12-01

157

Research on elementary particle physics  

SciTech Connect

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

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

1992-05-01

158

Meaning of counterfactual statements in quantum physics  

SciTech Connect

David Mermin suggests that my recent proof pertaining to quantum nonlocality is undermined by an essential ambiguity pertaining to the meaning of counterfactual statements in quantum physics. The ambiguity he cites arises from his imposition of a certain criterion for the meaningfulness of such counterfactual statements. That criterion conflates the meaning of a counterfactual statement with the details of a proof of its validity in such a way as to make the meaning of such a statement dependent upon the context in which it occurs. That dependence violates the normal demand in logic that the meaning of a statement be defined by the words in the statement itself, not by the context in which the statement occurs. My proof conforms to that normal requirement. I describe the context-independent meaning within my proof of the counterfactual statements in question. {copyright} {ital 1998 American Association of Physics Teachers.}

Stapp, H.P. [Lawrence Berkeley National Laboratory, University of California, Berkeley, California 94720 (United States)

1998-10-01

159

Field Theory of Yang-Mills Quantum Mechanics for D Particles  

NASA Astrophysics Data System (ADS)

We propose a new field-theoretic framework for formulating the non-relativistic quantum mechanics of D particles (D0 branes) in a Fock space of U(N) Yang-Mills theories with all different N simultaneously. D-particle field operators, which create and annihilate a D particle and hence change the value of N by one, are defined. The base space of these D-particle fields is a (complex) vector space of infinite dimension. The gauge invariance of Yang-Mills quantum mechanics is reinterpreted as a quantum-statistical symmetry, which is taken into account by setting up a novel algebraic and projective structure in the formalism. Ordinary physical observables of Yang-Mills theory, obeying the standard algebra, are expressed as bilinear forms of the D-particle fields. Together with the open-closed string duality, our new formulation suggests a trinity of three different but dual viewpoints of string theory.

Yoneya, T.

2007-08-01

160

On the Quantum Thinking of Physics Undergraduates  

Microsoft Academic Search

Using a questionnaire for data collection and two multivariate techniques for analysis, this paper reports on the concepts\\u000a undergraduate physics students in England hold regarding quantum phenomena. The analysis is by Cluster Analysis to find underlying\\u000a groups of concepts and Multidimensional Scaling to map the concepts onto a two-dimensional epistemological space. A sample\\u000a of 338 first and second year undergraduates,

Gren Ireson

161

Plato's TIMAIO? (TIMAEUS) and Modern Particle Physics  

NASA Astrophysics Data System (ADS)

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

Machleidt, Ruprecht

2005-04-01

162

Space-QUEST: quantum physics and quantum communication in space  

Microsoft Academic Search

Fundamental quantum optics test as well as quantum cryptography and quantum teleportation are based on the distribution of single quantum states and quantum entanglement respectively. We will discuss recent experimental achievements in the field of long-distance quantum communication via optical fiber as well as in free-space over a record breaking distance of 144 km. The European Space Agency (ESA) has

Rupert Ursin; Thomas Jennewein; Anton Zeilinger

2009-01-01

163

Quarked! - Adventures in Particle Physics Education  

NASA Astrophysics Data System (ADS)

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.

MacDonald, Teresa; Bean, Alice

2009-01-01

164

Two-particle quantum walks: Entanglement and graph isomorphism testing  

SciTech Connect

We study discrete-time quantum walks on the line and on general undirected graphs with two interacting or noninteracting particles. We introduce two simple interaction schemes and show that they both lead to a diverse range of probability distributions that depend on the correlations and relative phases between the initial coin states of the two particles. We investigate the characteristics of these quantum walks and the time evolution of the entanglement between the two particles from both separable and entangled initial states. We also test the capability of two-particle discrete-time quantum walks to distinguish nonisomorphic graphs. For strongly regular graphs, we show that noninteracting discrete-time quantum walks can distinguish some but not all nonisomorphic graphs with the same family parameters. By incorporating an interaction between the two particles, all nonisomorphic strongly regular graphs tested are successfully distinguished.

Berry, Scott D.; Wang, Jingbo B.

2011-04-15

165

The Coming Revolutions in Particle Physics  

NASA Astrophysics Data System (ADS)

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

Quigg, Chris

2006-12-01

166

Particle Physics Outreach to Secondary Education  

NASA Astrophysics Data System (ADS)

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.

Erik Johansson, K.; Jean Young, M.

2011-11-01

167

Quantum Groups in Two-Dimensional Physics  

NASA Astrophysics Data System (ADS)

This book is an introduction to integrability and conformal field theory in two dimensions using quantum groups. The book begins with a brief introduction to S-matrices, spin chains and vertex models as a prelude to the study of Yang-Baxter algebras and the Bethe ansatz. The authors then introduce the basic ideas of integrable systems, giving particular emphasis to vertex and face models. They give special attention to the underlying mathematical tools, including braid groups, knot invariants, and towers of algebras. The authors then go on to give a detailed introduction to quantum groups before addressing integrable models, two-dimensional conformal field theories, and superconformal field theories. The book contains many diagrams and exercises to illustrate key points in the text and will be appropriate for researchers and graduate students in theoretical physics and mathematics.

Gómez, Cisar; Ruiz-Altaba, Martín; Sierra, German

1996-04-01

168

Moore's law: new playground for quantum physics  

NASA Astrophysics Data System (ADS)

CMOS technology has been proven as one of the most important achievements in modern engineering history. In less than 30 years, it has become the primary engine driving the world economy. Device scaling makes this possible. For decades, progress in device scaling has followed an exponential curve: this has come to be known as Moore's law. Downscaling such devices like MOSFETs to their limiting sizes is a key challenge of the semiconductor industry now. Therefore device simulation requires new theory and modeling techniques, what helps to improve the understanding of device physics and design, for structures at the sub-100 nm scale, and complements experimental work in addressing this challenge. We present a new approach, which allows us to make predictions about performance of future MOSFETs. The quantum-mechanical features of the electron transport are extracted from the numerical solution of the quantum Liouville equation in the Wigner function representation.

van Rossum, M.; Schoenmaker, W.; Magnus, W.; de Meyer, K.; Croitoru, M. D.; Gladilin, V. N.; Fomin, V. M.; Devreese, J. T.

2003-05-01

169

Quantum Dots: An Experiment for Physical or Materials Chemistry  

ERIC Educational Resources Information Center

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

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

2005-01-01

170

Quantum backreaction through the Bohmian particle.  

PubMed

A novel solution to the quantum backreaction problem in a mixed quantum-classical simulation is provided using the Bohmian interpretation of quantum mechanics. The Bohmian backreaction is unique, computationally simple, features reaction channel branching, and easily gives the full classical limit. The Bohmian quantum-classical method is illustrated by application to a model of O2 interacting with a Pt surface. PMID:11327935

Prezhdo, O V; Brooksby, C

2001-04-01

171

Strange particle nuclear physics: Workshop summary  

SciTech Connect

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.

Dover, C.B.

1993-03-01

172

Strange particle nuclear physics: Workshop summary  

SciTech Connect

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.

Dover, C.B.

1993-03-01

173

Is Particle Physics Ready for the LHC?  

SciTech Connect

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

Lykken, Joseph

2006-04-05

174

Topics in Cosmology and Particle Physics.  

National Technical Information Service (NTIS)

In these three lectures, some of the major topics are reviewed which concern both particle physics and cosmology. In the first lecture, a general overview of the standard cosmological Big Bang model is given, and Big Bang nucleosynthesis is briefly gone o...

K. A. Olive

1985-01-01

175

Visions: The coming revolutions in particle physics  

SciTech Connect

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

Chris Quigg

2002-04-11

176

Particle decay in de sitter spacetime via quantum tunneling  

Microsoft Academic Search

The quantum tunneling process of decay of the composite particle in the de Sitter vacuum looks as thermal radiation with the\\u000a effective temperature twice larger than the Hawking temperature associated with the cosmological horizon.

G. E. Volovik

2009-01-01

177

Particles, Waves, and the Interpretation of Quantum Mechanics  

ERIC Educational Resources Information Center

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)

Christoudouleas, N. D.

1975-01-01

178

Efimov States in Nuclear and Particle Physics  

NASA Astrophysics Data System (ADS)

Particles with resonant short-range interactions have universal properties that do not depend on the details of their structure or their interactions at short distances. In the three-body system, these properties include the existence of a geometric spectrum of three-body Efimov states and a discrete scaling symmetry, which leads to log-periodic dependence of observables on the scattering length. Similar universal properties appear in the four-body system and possibly higher-body systems as well. For example, universal four-body states have recently been predicted and observed in experiments. These phenomena are often referred to as Efimov physics. We review their theoretical description and discuss applications in different areas of physics with a special emphasis on nuclear and particle physics.

Hammer, Hans-Werner; Platter, Lucas

2010-11-01

179

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

ERIC Educational Resources Information Center

|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…

Anderson, Bruce D.

2012-01-01

180

Quantum phase and quantum phase operators: some physics and some history  

Microsoft Academic Search

After reviewing the role of phase in quantum mechanics, I discuss, with the aid of a number of unpublished documents, the development of quantum phase operators in the 1960's. Interwoven in the discussion are the critical physics questions of the field: are there (unique) quantum phase operators and are there quantum systems which can determine their nature? I conclude with

Michael Martin Nieto

1993-01-01

181

Refined Characterization of Student Perspectives on Quantum Physics  

ERIC Educational Resources Information Center

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…

Baily, Charles; Finkelstein, Noah D.

2010-01-01

182

Refined Characterization of Student Perspectives on Quantum Physics  

ERIC Educational Resources Information Center

|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…

Baily, Charles; Finkelstein, Noah D.

2010-01-01

183

Designing Learning Environments to Teach Interactive Quantum Physics  

ERIC Educational Resources Information Center

|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…

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

2012-01-01

184

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

SciTech Connect

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.

Nedeljkovic, J.M.; Patel, R.C.; Kaufman, P.; Joyce-Pruden, C.; O'Leary, N. (Clarkson Univ., Potsdam, NY (United States))

1993-04-01

185

Sub-shot-noise quantum metrology with entangled identical particles  

Microsoft Academic Search

The usual notion of separability has to be reconsidered when applied to states describing identical particles. A definition of separability not related to any a priori Hilbert space tensor product structure is needed: this can be given in terms of commuting subalgebras of observables. Accordingly, the results concerning the use of the quantum Fisher information in quantum metrology are generalized

F. Benatti; R. Floreanini; U. Marzolino

2010-01-01

186

Entanglement and squeezing with identical particles: ultracold atom quantum metrology  

Microsoft Academic Search

In quantum metrological applications based on ultracold atom systems, entangled initial states are thought necessary to achieve sub-shot-noise accuracies. This conclusion, although strictly true for systems of distinguishable particles, does no longer hold for systems of identical particles. Indeed, while quantum non-locality is necessary, it can be encoded into the interferometric apparatus and not into the initial states. In particular,

F. Benatti; R. Floreanini; U. Marzolino

2011-01-01

187

On the Quantum Mechanical Scattering Statistics of Many Particles  

NASA Astrophysics Data System (ADS)

The probability of a quantum particle being detected in a given solid angle is determined by the S-matrix. The explanation of this fact in time-dependent scattering theory is often linked to the quantum flux, since the quantum flux integrated against a (detector-) surface and over a time interval can be viewed as the probability that the particle crosses this surface within the given time interval. Regarding many particle scattering, however, this argument is no longer valid, as each particle arrives at the detector at its own random time. While various treatments of this problem can be envisaged, here we present a straightforward Bohmian analysis of many particle potential scattering from which the S-matrix probability emerges in the limit of large distances.

Dürr, Detlef; Kolb, Martin; Moser, Tilo; Römer, Sarah

2010-09-01

188

Quantum walk on a line with two entangled particles  

SciTech Connect

We introduce the concept of a quantum walk with two particles and study it for the case of a discrete time walk on a line. A quantum walk with more than one particle may contain entanglement, thus offering a resource unavailable in the classical scenario and which can present interesting modifications on quantum walks with single particles. In this work, we show both numerically and analytically how the entanglement and the relative phase between the states describing the coin degree of freedom of each particle will influence the evolution of the quantum walk. In particular, the probability to find at least one particle in a certain position after N steps of the walk, as well as the average distance and the squared distance between the two particles, can be larger or smaller than the case of two unentangled particles, depending on the initial conditions we choose. This resource can then be tuned according to our needs to modify the features of a quantum walk. Experimental implementations are briefly discussed.

Omar, Y.; Paunkovic, N.; Sheridan, L.; Bose, S. [SQIG, Instituto de Telecomunicacoes and CEMAPRE, ISEG, Universidade Tecnica de Lisboa, P-1200-781 Lisbon (Portugal); SQIG, Instituto de Telecomunicacoes and Instituto Superior Tecnico, P-1049-001 Lisbon (Portugal); Institute for Quantum Computing, University of Waterloo, 200 University Avenue West, Waterloo, Ontario, N2L 3G5 (Canada); Department of Physics and Astronomy, University College London, Gower Street, London WC1E 6BT (United Kingdom)

2006-10-15

189

Innovative quantum technologies for microgravity fundamental physics and biological research  

NASA Astrophysics Data System (ADS)

The many advanced technology requirements dictated by the demanding low-Earth orbit research environment can only be satisfied through the adaptation of innovative methods and technologies. The fundamental physics research program in microgravity sponsors research that explores the physics governing matter, space, and time and that seeks to discover and understand the organizing principles of nature, including the emergence of complex structures. The fundamental physics research program currently supports research in four areas: gravitational and relativistic physics, laser cooling and atomic physics, low temperature and condensed matter physics, and biological physics. The microgravity fundamental physics is one of the science disciplines within the new NASA Office of Biological and Physical Sciences Research, where quantum technology plays a major role. Quantum technology, based on controlled manipulation of fundamentally quantum processes of atoms, molecules, or soft matter, enables novel and significantly extended capabilities. This paper presents a new technology program, within the fundamental physics research program, focusing on four quantum technology areas: quantum atomics, quantum optics, space superconductivity and quantum sensor technology, and quantum fluid based sensor and modeling technology.

Kierk, I.

190

Quantum stirring of particles in closed devices  

NASA Astrophysics Data System (ADS)

We study the quantum analogue of stirring of water inside a cup using a spoon. This can be regarded as a prototype example for quantum pumping in closed devices. The current in the device is induced by translating a scatterer. Its calculation is done using the Kubo formula approach. The transported charge is expressed as a line integral that encircles chains of Dirac monopoles. For simple systems, the results turn out to be counter-intuitive, e.g. as we move a small scatterer 'forward' the current is induced 'backwards'. One should realize that the route towards quantum-classical correspondence has to do with 'quantum chaos' considerations, and hence assumes greater complexity of the device. We also point out the relation to the familiar S-matrix formalism which is used to analyse quantum pumping in open geometries.

Rosenberg, Gilad; Cohen, Doron

2006-03-01

191

Current experiments in elementary particle physics. Revision  

SciTech Connect

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.

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

192

Numerical simulation of a quantum particle in a box  

Microsoft Academic Search

It is shown how one can get numerical prediction of quantum mechanical particle behaviour without using the Schrödinger equation. The main steps of this development are the non-differentiability hypothesis, the equations of motion entailed by this hypothesis, and the numerical formulation of a simple one-dimensional problem: the particle in a box.

Raphaël P. Hermann

1997-01-01

193

Charting the Course for Elementary Particle Physics  

SciTech Connect

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

Richter, Burton

2007-02-20

194

Cognitive Mapping of Advanced Level Physics Students' Conceptions of Quantum Physics.  

ERIC Educational Resources Information Center

|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…

Mashhadi, Azam; Woolnough, Brian

195

Quantum limited particle sensing in optical tweezers  

SciTech Connect

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.

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

196

Stochastic processes for indirectly interacting particles and stochastic quantum mechanics  

SciTech Connect

This work has two objectives. The first is to begin a mathematical formalism appropriate to treating particles which only interact with each other indirectly due to hypothesized memory effects in a stochastic medium. More specifically we treat a situation in which a sequence of particles consecutively passes through a region (e.g., a measuring apparatus) in such a way that one particle leaves the region before the next one enters. We want to study a situation in which a particle may interact with other particles that previously passed through the system via disturbances made in the region by these previous particles. Second, we apply the type of stochastic process appearing in this context to the stochastic interpretation of quantum mechanics to obtain a modified version of this interpretation. This version is free of many of the criticisms made against the stochastic interpretation of quantum mechanics.

Buonomano, V.; Prado de Andrade, A.F.

1988-04-01

197

Quantum chromodynamics at high energy and statistical physics  

NASA Astrophysics Data System (ADS)

When hadrons scatter at high energies, strong color fields, whose dynamics is described by quantum chromodynamics (QCD), are generated at the interaction point. If one represents these fields in terms of partons (quarks and gluons), the average number densities of the latter saturate at ultrahigh energies. At that point, nonlinear effects become predominant in the dynamical equations. The hadronic states that one gets in this regime of QCD are generically called “color glass condensates”. Our understanding of scattering in QCD has benefited from recent progress in statistical and mathematical physics. The evolution of hadronic scattering amplitudes at fixed impact parameter in the regime where nonlinear parton saturation effects become sizable was shown to be similar to the time evolution of a system of classical particles undergoing reaction-diffusion processes. The dynamics of such a system is essentially governed by equations in the universality class of the stochastic Fisher-Kolmogorov-Petrovsky-Piscounov equation, which is a stochastic nonlinear partial differential equation. Realizations of that kind of equations (that is, “events” in a particle physics language) have the form of noisy traveling waves. Universal properties of the latter can be taken over to scattering amplitudes in QCD. This review provides an introduction to the basic methods of statistical physics useful in QCD, and summarizes the correspondence between these two fields and its theoretical and phenomenological implications.

Munier, S.

2009-04-01

198

Current experiments in particle physics - particle data group  

SciTech Connect

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.

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

199

Green luminescence from copper doped zinc sulphide quantum particles  

Microsoft Academic Search

Free-standing powder of zinc sulphide quantum particles has been synthesized using a chemical route. X-ray diffraction analysis shows that the diameter of the particles is ?21±2 A? which is smaller than the Bohr exciton diameter for zinc sulphide. UV absorption shows an excitonic peak centered at ?300 nm corresponding to an energy gap of 4.1±0.1 eV. These particles show a

Ali Azam Khosravi; Manisha Kundu; Lalita Jatwa; S. K. Deshpande; U. A. Bhagwat; Murali Sastry; S. K. Kulkarni

1995-01-01

200

Process Ontology from Whitehead to Quantum Physics  

Microsoft Academic Search

Although Alfred North Whitehead probably did not know of the new quantum theory of Heisenberg, Schrodinger and Dirac, there seem to be deep similarities between his idea of the process and the ideas of quantum theory. Both Whitehead's metaphysics and quantum theory are theories of observations: The realities which quantum theory deals with are certain observations by scientists who use

Joachim Klose

2007-01-01

201

Studies in theoretical high energy particle physics. [Dept. of Physics, Univ. of Illinois at Chicago  

SciTech Connect

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.

Aratyn, H.; Brekke, L.; Keung, Wai-Yee; Sukhatme, U.

1993-01-01

202

Connecting nuclear physics to quantum chromodynamics  

SciTech Connect

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

Phillips, Daniel R. [Department of Physics and Astronomy, Ohio Unviersity, Athens, OH 45701 (United States)

2011-10-27

203

Teaching and Understanding of Quantum Interpretations in Modern Physics Courses  

ERIC Educational Resources Information Center

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

Baily, Charles; Finkelstein, Noah D.

2010-01-01

204

Proof-of-concept experiments for quantum physics in space  

Microsoft Academic Search

Quantum physics experiments in space using entangled photons and satellites are within reach of current technology. We propose a series of fundamental quantum physics experiments that make advantageous use of the space infrastructure with specific emphasis on the satellite-based distribution of entangled photon pairs. The experiments are feasible already today and will eventually lead to a Bell-experiment over thousands of

Rainer Kaltenbaek; Markus Aspelmeyer; Thomas Jennewein; Caslav Brukner; Anton Zeilinger; Martin Pfennigbauer; Walter R. Leeb

2004-01-01

205

Teaching and Understanding of Quantum Interpretations in Modern Physics Courses  

ERIC Educational Resources Information Center

|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

Baily, Charles; Finkelstein, Noah D.

2010-01-01

206

Tests of the particle physics-physical cosmology interface  

SciTech Connect

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.

Schramm, D.N. [Chicago Univ., IL (United States)]|[Fermi National Accelerator Lab., Batavia, IL (United States)

1993-01-01

207

Tests of the particle physics-physical cosmology interface  

SciTech Connect

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.

Schramm, D.N. (Chicago Univ., IL (United States) Fermi National Accelerator Lab., Batavia, IL (United States))

1993-01-01

208

Quantum dynamics as a physical resource  

SciTech Connect

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.

Nielsen, Michael A.; Dawson, Christopher M.; Dodd, Jennifer L.; Gilchrist, Alexei; Mortimer, Duncan; Osborne, Tobias J.; Bremner, Michael J.; Hines, Andrew [Centre for Quantum Computer Technology and Department of Physics, University of Queensland, Brisbane 4072 (Australia); Harrow, Aram W. [MIT Physics, 77 Massachusetts Avenue, Cambridge Massachusetts 02139 (United States)

2003-05-01

209

Summary of the particle physics and technology working group  

SciTech Connect

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

Stephan Lammel et al.

2002-12-10

210

Relativistic Quantum Physics at Your Pencil Tips: Dirac Fermion in Graphitic Carbon  

Microsoft Academic Search

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

Philip Kim

2007-01-01

211

The Particle Physics Data Grid. Final Report  

SciTech Connect

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

Livny, Miron

2002-08-16

212

Problems of singularity particle horizon and flatness in quantum cosmology  

SciTech Connect

Classical relativistic cosmology is known to have the space-time singularity as an inevitable feature. The standard big bang models have very small particle horizons in the early stages which make it difficult to understand the observed homogeneity in the universe. The relatively narrow range of the observed matter density in the neighbourhood of closure density requires highly fine tuning of the early universe. In this paper it is argued that these three problems can be satisfactorily resolved in quantum cosmology. It is shown that it is extremely unlikely that the universe evolved to the present state from quantum states with singulrity and particle horizon. Similarly, it is shown that of all possible states the Robertson--Walker model of flat spatial sections is the most likely state for the universe to evolve out of a quantum fluctuation. To demonstrate these results a suitable formalism for quantum cosmology is first developed.

Narlikar, J.V.; Padmanabhan, T.

1983-10-15

213

Particle Physics: A New Course for Schools and Colleges.  

ERIC Educational Resources Information Center

|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)|

Swinbank, Elizabeth

1992-01-01

214

Quantum entanglement in random physical states.  

PubMed

Most states in the Hilbert space are maximally entangled. This fact has proven useful to investigate--among other things--the foundations of statistical mechanics. Unfortunately, most states in the Hilbert space of a quantum many-body system are not physically accessible. We define physical ensembles of states acting on random factorized states by a circuit of length k of random and independent unitaries with local support. We study the typicality of entanglement by means of the purity of the reduced state. We find that for a time k=O(1), the typical purity obeys the area law. Thus, the upper bounds for area law are actually saturated, on average, with a variance that goes to zero for large systems. Similarly, we prove that by means of local evolution a subsystem of linear dimensions L is typically entangled with a volume law when the time scales with the size of the subsystem. Moreover, we show that for large values of k the reduced state becomes very close to the completely mixed state. PMID:23006070

Hamma, Alioscia; Santra, Siddhartha; Zanardi, Paolo

2012-07-26

215

Wigner crystal physics in quantum wires.  

SciTech Connect

The physics of interacting quantum wires has attracted a lot of attention recently. When the density of electrons in the wire is very low, the strong repulsion between electrons leads to the formation of a Wigner crystal. We review the rich spin and orbital properties of the Wigner crystal, in both the one-dimensional and the quasi-one-dimensional regimes. In the one-dimensional Wigner crystal the electron spins form an antiferromagnetic Heisenberg chain with exponentially small exchange coupling. In the presence of leads, the resulting inhomogeneity of the electron density causes a violation of spin-charge separation. As a consequence the spin degrees of freedom affect the conductance of the wire. Upon increasing the electron density, the Wigner crystal starts deviating from the strictly one-dimensional geometry, forming a zigzag structure instead. Spin interactions in this regime are dominated by ring exchanges, and the phase diagram of the resulting zigzag spin chain has a number of unpolarized phases as well as regions of complete and partial spin polarization. Finally we address the orbital properties in the vicinity of the transition from a one-dimensional to a quasi-one-dimensional state. Due to the locking between chains in the zigzag Wigner crystal, only one gapless mode exists. Manifestations of Wigner crystal physics at weak interactions are explored by studying the fate of the additional gapped low-energy mode as a function of interaction strength.

Meyer, J. S.; Matveev, K. A.; Materials Science Division; Ohio State Univ.

2009-01-14

216

Teaching and understanding of quantum interpretations in modern physics courses  

NSDL National Science Digital Library

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 courses recently taught at the University of Colorado, and examine associated impacts on student perspectives regarding quantum physics. We find students are more likely to prefer realist interpretations of quantum-mechanical systems when instructors are less explicit in addressing student ontologies. We also observe contextual variations in student beliefs about quantum systems, indicating that instructors who choose to address questions of ontology in quantum mechanics should do so explicitly across a range of topics.

Baily, Charles; Finkelstein, Noah D.

2010-03-11

217

Teaching and understanding of quantum interpretations in modern physics courses  

NASA Astrophysics Data System (ADS)

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 courses recently taught at the University of Colorado, and examine associated impacts on student perspectives regarding quantum physics. We find students are more likely to prefer realist interpretations of quantum-mechanical systems when instructors are less explicit in addressing student ontologies. We also observe contextual variations in student beliefs about quantum systems, indicating that instructors who choose to address questions of ontology in quantum mechanics should do so explicitly across a range of topics.

Baily, Charles; Finkelstein, Noah D.

2010-06-01

218

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

SciTech Connect

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

Shotter, A. C. [School of Physics and Astronomy, University of Edinburgh, Edinburgh, United Kingdom and TRIUMF, Vancouver (Canada); Shotter, M. D. [Department of Physics, University of Oxford, Oxford (United Kingdom)

2011-05-15

219

Eulerian and Newtonian dynamics of quantum particles  

NASA Astrophysics Data System (ADS)

We derive the classical equations of hydrodynamics (the Euler and continuity equations), from which the Schrödinger equation follows as a limit case. It is shown that the statistical ensemble corresponding to a quantum system and described by the Schrödinger equation can be considered an inviscid gas that obeys the ideal gas law with a quickly oscillating sign-alternating temperature. This statistical ensemble performs the complex movements consisting of smooth average movement and fast oscillations. It is shown that the average movements of the statistical ensemble are described by the Schrödinger equation. A model of quantum motion within the limits of classical mechanics that corresponds to the hydrodynamic system considered is suggested.

Rashkovskiy, S. A.

2013-06-01

220

The experimental foundations of particle physics  

SciTech Connect

This book describes the development of modern particle physics, emphasizing the role and significance of crucial experiments. This description is supported by a selection of reprints of notable experimental papers. Beginning at the turn of the century with the discovery of radioactivity, x-rays, and the Thomson model of the atom, the authors take the reader through the great developments of the twentieth century, culminating in a description of the electroweak theory and the discovery of the W and Z vector bosons. The bulk of this book is written in non-technical language, although more technical passages are included and extensive references to review articles and books are given.

Cahn, R.N.; Goldhaber, G.

1987-01-01

221

Quantum physics: Watching the wavefunction collapse  

NASA Astrophysics Data System (ADS)

The continuous random path of a superconducting system's quantum state has been tracked as the state changes during measurement. The results open the possibility of steering quantum systems into a desired state. See Letter p.211

Jordan, Andrew N.

2013-10-01

222

Toward unification of elementary particle physics and cosmology in 10-dimensions  

SciTech Connect

Ten-dimensions seem to be a unique setting for unifying at the classical level cosmology and elementary particle physics. Some interesting results along these lines are obtained starting with a Yang-Mills coupled to supergravity theory in 10-dimensions. However, further progress will require finding an underlying quantum theory.

Chapline, G.; Gibbons, G.

1984-06-14

223

Attention, Intention, and Will in Quantum Physics  

SciTech Connect

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.

Stapp, H.P.

1999-05-01

224

Quantum Field Theory in Condensed Matter Physics  

NASA Astrophysics Data System (ADS)

Preface; Acknowledgements; Part I. Introduction to Methods: 1. QFT: language and goals; 2. Connection between quantum and classical: path integrals; 3. Definitions of correlation functions: Wick's theorem; 4. Free bosonic field in an external field; 5. Perturbation theory: Feynman diagrams; 6. Calculation methods for diagram series: divergences and their elimination; 7. Renormalization group procedures; 8. O(N)-symmetric vector model below the transition point; 9. Nonlinear sigma models in two dimensions: renormalization group and 1/N-expansion; 10. O(3) nonlinear sigma model in the strong coupling limit; Part II. Fermions: 11. Path integral and Wick's theorem for fermions; 12. Interaction electrons: the Fermi liquid; 13. Electrodynamics in metals; 14. Relativistic fermions: aspects of quantum electrodynamics; 15. Aharonov-Bohm effect and transmutation of statistics; Part III. Strongly Fluctuating Spin Systems: Introduction; 16. Schwinger-Wigner quantization procedure: nonlinear sigma models; 17. O(3) nonlinear sigma model in (2+1) dimensions: the phase diagram; 18. Order from disorder; 19. Jordan-Wigner transformations for spin S=1/2 models in D=1, 2, 3; 20. Majorana representation for spin S=1/2 magnets: relationship to Z2 lattice gauge theories; 21. Path integral representations for a doped antiferromagnet; Part IV. Physics in the World of One Spatial Dimension: Introduction; 22. Model of the free bosonic massless scalar field; 23. Relevant and irrelevant fields; 24. Kosterlitz-Thouless transition; 25. Conformal symmetry; 26. Virasoro algebra; 27. Differential equations for the correlation functions; 28. Ising model; 29. One-dimensional spinless fermions: Tomonaga-Luttinger liquid; 30. One-dimensional fermions with spin: spin-charge separation; 31. Kac-Moody algebras: Wess-Zumino-Novikov-Witten model; 32. Wess-Zumino-Novikov-Witten model in the Lagrangian form: non-Abelian bosonization; 33. Semiclassical approach to Wess-Zumino-Novikov-Witten models; 34. Integrable models: dynamical mass generation; 35. A comparative study of dynamical mass generation in one and three dimensions; 36. One-dimensional spin liquids: spin ladder and spin S=1 Heisenberg chain; 37. Kondo chain; 38. Gauge fixing in non-Abelian theories: (1+1)-dimensional quantum chromodynamics; Select bibliography; Index.

Tsvelik, Alexei M.

2007-01-01

225

Quantum physics explains Newton's laws of motion  

Microsoft Academic Search

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

Jon Ogborn; Edwin F. Taylor

2005-01-01

226

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

SciTech Connect

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.

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

1992-09-01

227

Statistical Particle Tracking Velocimetry using Single Molecule and Quantum Dot Tracers  

NASA Astrophysics Data System (ADS)

Particle Tracking Velocimetry (PTV) with nanometer resolution is demonstrated using single molecules and quantum dots (QD) as tracer particles. Several problems are unique to this regime, including: shot noise from intensified cameras, large drop- in/drop-out (due to Brownian motion and QD blinking), sub-pixel tracer intensity profiles and lastly issues associated with tracking with high particle seeding densities. We have developed a statistical particle tracking method to successfully address these problems. The algorithm tracks all possible particles, removing non-physical matches using the global statistical properties of the system, leaving the true particle displacement distribution (and hence velocity). The algorithm is validated using FITC-Dextran molecules and QDs. Experiumental results concerning the velocity and diffusion characteristics of the nanoscale tracers are reported.

Guasto, Jeff

2005-11-01

228

Relational Particle Models as Toy Models for Quantum Gravity and Quantum Cosmology  

Microsoft Academic Search

It is argued that substantial portions of both Newtonian particle mechanics and general relativity can be viewed as relational (rather than absolute) theories. I furthermore use the relational particle models as toy models to investigate the problem of time in closed-universe canonical quantum general relativity. I consider thus in particular the internal time, semiclassical and records tentative resolutions of the

Edward Anderson

2006-01-01

229

Interpretive themes in quantum physics: Curriculum development and outcomes  

NASA Astrophysics Data System (ADS)

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 prior work has shown that student perspectives on the physical interpretation of quantum mechanics can be characterized, and are differentially influenced by the myriad ways instructors approach interpretive themes in their introductory courses. We report how a transformed modern physics curriculum (recently implemented at the University of Colorado) has positively impacted student perspectives on quantum physics, by making questions of classical and quantum reality a central theme of the course, but also by making the beliefs of students (and not just those of scientists) an explicit topic of discussion.

Baily, Charles; Finkelstein, Noah D.

2012-02-01

230

Interpretive Themes in Quantum Physics: Curriculum Development and Outcomes  

NSDL National Science Digital Library

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 prior work has shown that student perspectives on the physical interpretation of quantum mechanics can be characterized, and are differentially influenced by the myriad ways instructors approach interpretive themes in their introductory courses. We report how a transformed modern physics curriculum (recently implemented at the University of Colorado) has positively impacted student perspectives on quantum physics, by making questions of classical and quantum reality a central theme of the course, but also by making the beliefs of students (and not just those of scientists) an explicit topic of discussion.

Baily, Charles; Finkelstein, Noah D.

2012-04-24

231

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

SciTech Connect

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.

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

232

Decoherence of quantum kinematical correlations: Elastic scattering of identical particles  

NASA Astrophysics Data System (ADS)

We include the dynamics of the angular straggling process in the angular distributions of Mott scattering of heavy ions. We model the passage of an incoming nucleus through a target as a diffusion process. It is then possible to derive a simple and physically transparent expression for the angular dispersion due to the straggling. The angular dispersion should be folded with the theoretical Mott cross section to see its effect on the amplitude of the Mott oscillations. Our results agree very well with data of 208Pb + 208Pb scattering. We define the “classical” limit as the limit when the angular dispersion due to straggling becomes comparable with the Mott oscillation period and get the disappearance of quantum interference occurring at the limit 0.050?(Z4)/(E3/2)?1, where ? stands for the target thickness, Z is the system's charge, and E is the center-of-mass energy. The experiments on lead are very close to this limit. We show that the kinematical correlations due to the identity of the particles is maintained, as it should be, and the action of the environment is to reduce the fringe visibility.

Morais, M. C.; Nemes, M. C.; Lichtenthäler, R.; Lépine-Szily, A.

2012-11-01

233

Generation of quantum logic operations from physical Hamiltonians  

Microsoft Academic Search

We provide a systematic analysis of the physical generation of single- and two-qubit quantum operations from Hamiltonians available in various quantum systems for scalable quantum information processing. We show that generation of single-qubit operations can be transformed into a steering problem on the Bloch sphere, which represents all Rz -equivalence classes of single-qubit operations, whereas the two-qubit problem can be

Jun Zhang; K. Birgitta Whaley

2005-01-01

234

Puzzles in Hadronic Physics and Novel Quantum Chromodynamics Phenomenology  

NASA Astrophysics Data System (ADS)

We review some outstanding puzzles and experimental anomalies in hadron physics that appear to challenge conventional wisdom and, in some cases, the foundations of quantum chromodynamics (QCD). We also discuss possible solutions and propose new tests and experiments that could illuminate the underlying physics and novel phenomenological features of QCD. In some cases, new perspectives for QCD physics have emerged.

Brodsky, Stanley J.; de Téramond, Guy; Karliner, Marek

2012-11-01

235

Are Classical Tachyons Slower-Than-Light Quantum Particles.  

National Technical Information Service (NTIS)

After having studied the shape that a tachyon T (e.g., intrinsecally spherical) would take up, it is shown in an explicit example that the characteristic of classical tachyons are similar to those of the ordinary (slower-than-light) quantum particles. In ...

E. Recami G. D. Maccarrone

1983-01-01

236

Phase diagram of the dissipative quantum particle in a box  

Microsoft Academic Search

We analyze the phase diagram of a quantum particle confined to a finite chain and subjected to a dissipative environment described by an ohmic spectral function. Analytical and numerical techniques are employed to explore both the perturbative and nonperturbative regimes of the model. For small dissipation of the coupling to the environment leads to a narrowing of the density distribution

J. Sabio; L. Borda; F. Guinea; F. Sols

2008-01-01

237

Quantum Hall Physics in String Theory  

Microsoft Academic Search

In certain backgrounds string theory exhibits quantum Hall-like behavior. These backgrounds provide an explicit realization of the effective non-commutative gauge theory description of the fractional quantum Hall effect (FQHE), and of the corresponding large N matrix model. I review results on the string theory realization of the two-dimensional fractional quantum Hall fluid (FQHF), and describe new results on the stringy

Oren Bergman

2004-01-01

238

Particle in a Box: Software for computer-assisted learning in introductory quantum mechanics courses  

Microsoft Academic Search

Particle in a Box is a non-commercial program which was devised to help students to become familiar with typical quantum phenomena when they are introduced for the first time in a physical-chemistry course. Its name comes from the simple and well-known theoretical model on which it is based. The user can select three distinct potential wells, namely the one dimensional

A L Magalhães; V P S Vasconcelos

2006-01-01

239

The Second Law and Quantum Physics  

NASA Astrophysics Data System (ADS)

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

Bennett, Charles H.

2008-08-01

240

The evolution of nanoscale quantum effects in semiconductor physics  

Microsoft Academic Search

In the early twentieth century, encounters with physical phenomena which require detailed analyses in nanoscale, such as electron motion, prompted the advent of quantum mechanics, since Newtonian mechanics could not possibly provide an adequate explanation for them. Electron tunneling through nanoscale barriers is the most direct consequence of the law of quantum mechanics, for which the Esaki tunnel diode gave

Leo Esaki

1999-01-01

241

Unitary quantum physics with time-space noncommutativity  

Microsoft Academic Search

In this work quantum physics in noncommutative spacetime is developed. It is based on the work of Doplicher et al. which allows for time-space noncommutativity. The Moyal plane is treated in detail. In the context of noncommutative quantum mechanics, some important points are explored, such as the formal construction of the theory, symmetries, causality, simultaneity and observables. The dynamics generated

Aiyalam P. Balachandran; Thupil R. Govindarajan; Carlos Molina Mendes; Paulo Teotonio-Sobrinho

2004-01-01

242

Unitary quantum physics with time-space non-commutativity  

Microsoft Academic Search

In these lectures4 quantum physics in noncommutative spacetime is developed. It is based on the work of Doplicher et al. which allows for time-space noncommutativity. In the context of noncommutative quantum mechanics, some important points are explored, such as the formal construction of the theory, symmetries, causality, simultaneity and observables. The dynamics generated by a noncommutative Schrödinger equation is studied.

A. P. Balachandran; T. R. Govindarajan; A. G. Martins; C. Molina; P. Teotonio-Sobrinho

2005-01-01

243

Quantum maximum entropy principle for a system of identical particles  

SciTech Connect

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.

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

244

Entanglement of indistinguishable particles in condensed-matter physics  

Microsoft Academic Search

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

Mark R. Dowling; Andrew C. Doherty; Howard M. Wiseman

2006-01-01

245

Energy related applications of elementary particle physics  

SciTech Connect

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

Rafelski, J.

1991-08-31

246

Particle physics confronts the solar neutrino problem  

SciTech Connect

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.

Pal, P.B.

1991-06-01

247

Some calculator programs for particle physics  

NASA Astrophysics Data System (ADS)

Seven calculator programs that do simple chores that arise in elementary particle physics are given. LEGENDRE evaluates the Legendre polynomial series. ASSOCIATED LEGENDRE evaluates the first associated Legendre polynomial series. CONFIDENCE calculates confidence levels for chi(2), Gaussian, or Poisson probability distributions. TWO BODY calculates the c.m. energy, the initial and final state c.m. momenta, and the extreme values of t and u for a two body reaction. ELLIPSE calculates coordinates of points for drawing an ellipse plot showing the kinematics of a two body reaction or decay. DALITZ RECTANGULAR calculates coordinates of points on the boundary of a rectangular Dalitz plot. DALITZ TRIANGULAR calculates coordinates of points on the boundary of a triangular Dalitz plot. There are short versions of CONFIDENCE (EVEN N and POISSON) that calculate confidence levels for the even degree of freedom chi(2) and the Poisson cases. The programs are written for the HP-97 calculator.

Whol, C. G.

1982-01-01

248

A New Model Course in Applied Quantum Physics: Examination Questions  

NSDL National Science Digital Library

These examination questions measure the learner's comprehension of key concepts in an introductory applied quantum mechanics course. Each set of questions is accompanied by pertinent results from physics education research. The questions require a password, which is available by email.

Redish, Edward F.; Steinberg, Richard N.; Wittmann, Michael C.

2005-07-26

249

Relativistic, quantum theory of spinor particles in a gravitational field  

SciTech Connect

A relativistic quantum theory of spinor particles in a gravitational field is constructed on the basis of Minkowski space and a gravitational field in the spirit of Faraday and Maxwell. Relativistic equations describing the change in the generalized 4-momentum of a particle and its intrinsic angular momentum in a gravitational field are obtained in the semiclassical approximation. It is shown that that all the well-known gravitational effects can be explained by the constructed theory and that the theoretical results agree with the experimental results. It follows naturally from the theory that the vacuum is unstable and that particles are produced in a gravitational field.

Logunov, A.A.; Loskutov, Yu.M.

1986-10-01

250

Quantum Particles Passing Through a Matter-Wave Aperture  

NASA Astrophysics Data System (ADS)

In this paper, we investigate theoretically a dilute stream of free quantum particles passing through a macroscopic circular aperture of matter-waves and then moving in a space at a finite temperature, taking into account the dissipative coupling with the environment. The portion of particles captured by the detection screen is studied by varying the distance between the aperture and the screen. Depending on the wavelength, the temperature, and the dimension of the aperture, an unusual local valley-peak structure is found in increasing the distance, in contrast to traditional thinking that it decreases monotonically. The underlying mechanism is the nonlocality in the process of decoherence for an individual particle.

Peng, Jian-Ping

2013-10-01

251

Particle physics---Experimental. Annual progress report  

SciTech Connect

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

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

1991-08-21

252

Matter and Interactions: A Particle Physics Perspective  

ERIC Educational Resources Information Center

|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…

Organtini, Giovanni

2011-01-01

253

Quantum statistical correlations and single-particle distributions for slowly expanding systems with temperature profile  

SciTech Connect

Competition among particle evaporation, temperature gradient, and flow is investigated in a phenomenological manner, based on a simultaneous analysis of quantum statistical correlations and momentum distributions for a nonrelativistic, spherically symmetric, three-dimensionally expanding, finite source. The parameters of the model emission function are constrained by fits to neutron and proton momentum distributions and correlation functions in intermediate-energy heavy-ion collisions. The temperature gradient is related to the momentum dependence of the radius parameters of the two-particle correlation function, as well as to the momentum-dependent temperature parameter of the single particle spectrum, while a long duration of particle evaporation is found to be responsible for the low relative momentum behavior of the two-particle correlations. {copyright} {ital 1997} {ital The American Physical Society}

Helgesson, J. [ECT, European Centre for Studies in Theoretical Nuclear Physics and Related Areas, Villa Tambosi, Strada delle Tarabelle 286, I-38050 Villazzano (Trento) (Italy)] Csoumlrgodblac, T. [MTA KFKI RMKI, H--1525 Budapest 114, P.O. Box 49 (Hungary)] Csoumlrgodblac, T. [Department of Physics, Columbia University, 538 W 120th Street, New York, New York 10027 (United States)] Asakawa, M. [Department of Physics, School of Science, Nagoya University, Nagoya, 464-01 (Japan)] Loumlrstad, B. [Department of Physics, University of Lund, Box 118, S-221 00 Lund (Sweden)

1997-11-01

254

Localization and Pattern Formation in Quantum Physics  

Microsoft Academic Search

ABSTRACT In this second part we present a set of methods, analytical and numerical, which can describe behaviour in (non) equilibrium ensembles, both classical and quantum, especially in the complex systems, where the standard approaches cannot be applied. The key points demonstrating advantages of this approach are: (i) eects of localization of possible quantum states; (ii) eects of non-perturbative multiscales

Antonina N. Fedorova; Michael G. Zeitlin

255

Detectors for probing relativistic quantum physics beyond perturbation theory  

NASA Astrophysics Data System (ADS)

We develop a general formalism for a nonperturbative treatment of harmonic-oscillator particle detectors in relativistic quantum field theory using continuous-variable 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 nonperturbatively—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 behavior 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).

Brown, Eric G.; Martín-Martínez, Eduardo; Menicucci, Nicolas C.; Mann, Robert B.

2013-04-01

256

Particle Physics in a Season of Change  

SciTech Connect

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.

Quigg, Chris

2012-02-01

257

Multiparty quantum key agreement with single particles  

NASA Astrophysics Data System (ADS)

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.

Liu, Bin; Gao, Fei; Huang, Wei; Wen, Qiao-yan

2013-04-01

258

GENERAL: Efficient Quantum Secure Communication Protocol by Rearranging Particle Orders  

NASA Astrophysics Data System (ADS)

We propose a quantum secure communication protocol by using three-particle GHZ states. In this protocol, we utilize the ideas of the rearranging orders and the sequence transmission. The sender of messages, Alice, first disturbs the particle orders in an initial sequence, and then sends the sequence of the disturbed orders to the receiver of messages, Bob. Under Alice's introduction, Bob rearranges the sequence back to the initial sequence. By making a GHZ state measurement on each of the three particles in turn, Bob can attain Alice's secret messages. In addition, we still calculate the efficiency of our three-particle GHZ protocol and generalize it to the case using multi-particle GHZ state.

Gao, Gan

2009-11-01

259

Long-time behavior of many-particle quantum decay  

SciTech Connect

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

Campo, A. del [Institut fuer Theoretische Physik, Leibniz Universitaet Hannover, Appelstrasse 2, D-30167 Hannover (Germany)

2011-07-15

260

Classical diffusion of a quantum particle in a noisy environment.  

PubMed

We study the spreading of a quantum-mechanical wave packet in a tight-binding model with a noisy potential and analyze the emergence of classical diffusion from the quantum dynamics due to decoherence. We consider a finite correlation time of the noisy environment and treat the system by utilizing the separation of fast (dephasing) and slow (diffusion) processes. We show that classical diffusive behavior emerges at long times and we calculate analytically the dependence of the classical diffusion coefficient on the noise magnitude and correlation time. This method provides a general solution to this problem for arbitrary conditions of the noisy environment. The calculation can be done in any dimension, but we demonstrate it in one dimension for clarity of representation. The results are relevant to a large variety of physical systems, from electronic transport in solid-state physics to light transmission in optical devices, diffusion of excitons, and quantum computation. PMID:19518400

Amir, Ariel; Lahini, Yoav; Perets, Hagai B

2009-05-22

261

Classical diffusion of a quantum particle in a noisy environment  

NASA Astrophysics Data System (ADS)

We study the spreading of a quantum-mechanical wave packet in a tight-binding model with a noisy potential and analyze the emergence of classical diffusion from the quantum dynamics due to decoherence. We consider a finite correlation time of the noisy environment and treat the system by utilizing the separation of fast (dephasing) and slow (diffusion) processes. We show that classical diffusive behavior emerges at long times and we calculate analytically the dependence of the classical diffusion coefficient on the noise magnitude and correlation time. This method provides a general solution to this problem for arbitrary conditions of the noisy environment. The calculation can be done in any dimension, but we demonstrate it in one dimension for clarity of representation. The results are relevant to a large variety of physical systems, from electronic transport in solid-state physics to light transmission in optical devices, diffusion of excitons, and quantum computation.

Amir, Ariel; Lahini, Yoav; Perets, Hagai B.

2009-05-01

262

Quantum Ground State and Minimum Emittance of a Fermionic Particle Beam in a Circular Accelerator  

NASA Astrophysics Data System (ADS)

In the usual parameter regime of accelerator physics, particle ensembles can be treated as classical. If we approach a regime where epsilon _x epsilon _y epsilon _s approx N_{particles} ? _{Compton}^3, however, the granular structure of quantum-mechanical phase space becomes a concern. In particular, we have to consider the Pauli exclusion principle, which will limit the minimum achievable emittance for a beam of fermions. We calculate these lowest emittances for the cases of bunched and coasting beams at zero temperature and their first-order change rate at finite temperature.

Kabel, Andreas C.

2002-04-01

263

Quantum equivalence principle and finite particle creation in expanding universes  

SciTech Connect

A formulation of the equivalence principle in quantum field theory is introduced. The quantum equivalence principle yields implementable Bogolyubov transformations. In this way we find a theory for a scalar field in curved space--time where particle creation is finite for every value of the coupling constant. In the particular case of conformal coupling the initial conditions of positive and negative frequency wave functions coincide with the ones of a first order WKB approximation. The coefficients of the Bogolyubov transformations are exactly computed and the created energy density is also finite.

Castagnino, M.; Weder, R.

1981-01-01

264

Spacetime alternatives in the quantum mechanics of a relativistic particle  

SciTech Connect

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

Whelan, J.T. (Department of Physics, University of California, Santa Barbara, California 93106-9530 (United States) Isaac Newton Institute for Mathematical Sciences, 20 Clarkson Road, Cambridge, CB3 0EH (United Kingdom))

1994-11-15

265

Refined characterization of student perspectives on quantum physics  

NSDL National Science Digital Library

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 physics concepts, and to inform how we might teach traditional content. Our previous investigations of student perspectives on quantum physics have indicated they can be highly nuanced, and may vary both within and across contexts. In order to better understand the contextual and often seemingly contradictory stances of students on matters of interpretation, we interviewed 19 students from four introductory modern physics courses taught at the University of Colorado. We find that students have attitudes and opinions that often parallel the stances of expert physicists when arguing for their favored interpretations of quantum mechanics, allowing for more nuanced characterizations of student perspectives in terms of three key interpretive themes. We present a framework for characterizing student perspectives on quantum mechanics, and demonstrate its utility in interpreting the sometimes contradictory nature of student responses to previous surveys. We further find that students most often vacillate in their responses when what makes intuitive sense to them is not in agreement with what they consider to be a correct response, underscoring the need to distinguish between the personal and the public perspectives of introductory modern physics students.

Baily, Charles; Finkelstein, Noah D.

2012-01-20

266

Scheduling physical operations in a quantum information processor  

NASA Astrophysics Data System (ADS)

Irrespective of the underlying technology used to implement a large-scale quantum architecture system, one of the central challenges of accurately modeling the architecture is the ability to map and schedule a quantum application onto a physical grid while taking into account the cost of communication, the classical resources, and the maximum exploitable parallelism. In this paper we introduce and evaluate a physical operations scheduler for arbitrary quantum circuits. Our scheduler accepts a description of a circuit together with a description of a specific physical layout and outputs a sequence of operations that expose the required communication and available parallelism in the circuit. The output of the scheduler is a quantum assembly language file that can directly be simulated on a set of available tools.

Metodi, Tzvetan S.; Thaker, Darshan D.; Cross, Andrew W.; Chong, Frederic T.; Chuang, Isaac L.

2006-06-01

267

The Physical Principles of Particle Detectors.  

ERIC Educational Resources Information Center

|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)|

Jones, Goronwy Tudor

1991-01-01

268

The Physical Principles of Particle Detectors.  

ERIC Educational Resources Information Center

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)

Jones, Goronwy Tudor

1991-01-01

269

Quantum physics: Qubits ride the photon bus  

Microsoft Academic Search

Quantum mechanics using whole electrical circuits might seem a far-fetched idea. But make the circuits superconducting, and they can be used to send and collect single photons, rather like atoms do --- only better.

Antti O. Niskanen; Yasunobu Nakamura

2007-01-01

270

Attention, Intention, and Will in Quantum Physics  

Microsoft Academic Search

The need for a self-observing quantum system to pose questions leads to a\\u000atripartite quantum process involving a Schroedinger process that is local\\u000adeterministic, a Heisenberg process that poses the question, and a Dirac\\u000aprocess that picks the answer. In the classical limit where Planck's constant\\u000ais set to zero these three processes reduce to one single deterministic\\u000aclassical process:

Henry P. Stapp

1999-01-01

271

Quantum Speed Limit for Physical Processes  

NASA Astrophysics Data System (ADS)

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.

Taddei, M. M.; Escher, B. M.; Davidovich, L.; de Matos Filho, R. L.

2013-02-01

272

Let's call it Nonlocal Quantum Physics  

Microsoft Academic Search

In the following we undertake to derive quantum theory as a stochastic low-energy and coarse-grained theory from a more primordial discrete and basically geometric theory living on the Planck scale and which (as we argue) possibly underlies also \\\\tit{string theory}. We isolate the so-called \\\\tit{ideal elements} which represent at the same time the cornerstones of the framework of ordinary quantum

Manfred Requardt

2000-01-01

273

Wave-particle duality and uncertainty principle: Phenomenographic categories of description of tertiary physics studentsâ depictions  

NSDL National Science Digital Library

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

Ayene, Mengesha; Kriek, Jeanne; Damtie, Baylie

2012-05-21

274

Quantum physics with non-Hermitian operators Quantum physics with non-Hermitian operators  

NASA Astrophysics Data System (ADS)

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

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

2012-11-01

275

Quantum, cyclic, and particle-exchange heat engines  

NASA Astrophysics Data System (ADS)

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.

Humphrey, T. E.; Linke, H.

2005-10-01

276

Making the Transition from Classical to Quantum Physics  

ERIC Educational Resources Information Center

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…

Dutt, Amit

2011-01-01

277

Open Source Physics Curricular Material for Quantum Mechanics  

NSDL National Science Digital Library

The Open Source Physics Curricular Material paper describes the interactive curricular material created as part of the Open Source Physics project for the teaching and learning of quantum mechanics. Here we focus on the measurement and time evolution of two-state superpositions in the context of bound states and spin.

Belloni, Mario; Christian, Wolfgang; Brown, Douglas

2008-05-30

278

Pre-Service Physics Teachers' Comprehension of Quantum Mechanical Concepts  

ERIC Educational Resources Information Center

|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…

Didis, Nilufer; Eryilmaz, Ali; Erkoc, Sakir

2010-01-01

279

Making the Transition from Classical to Quantum Physics  

ERIC Educational Resources Information Center

|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…

Dutt, Amit

2011-01-01

280

Nanoscale Quantum Devices from an Atomic Physics Perspective  

Microsoft Academic Search

Nanometer-scale semiconductor devices are often hailed as ``artificial atoms,'' whose quantum mechanical properties can be tailor-made to fit any desired application. Here I take the artificial atom concept seriously, bringing the methods of theoretical atomic physics to bear on calculations of nanostructure physics. Electron transport through such a device can be modelled as a scattering process, in which the complicated

John L. Bohn

1996-01-01

281

Topics in quantum physics with origins in astronomy: Two examples  

NASA Astrophysics Data System (ADS)

Astronomy has provided the inspiration for several investigations in quantum physics. These topics can serve as pedagogical vehicles for undergraduate courses in physics and astronomy. Two examples are considered, atoms in strong magnetic fields and the negative ion of hydrogen. Both are fundamental problems of quantum physics which involve basic principles and techniques and are of practical interest and historically important. They also provide, in a form accessible to undergraduates, analogs of exotic topics such as the stability at a saddle of a potential surface, supersymmetry, dimensional reduction, and models for fundamental constants.

Rau, A. R. P.

2012-05-01

282

Early history of cosmic particle physics  

NASA Astrophysics Data System (ADS)

The discovery of cosmic rays is a standard example of `one man's noise is another man's signal'. From the apparently minor leakages of electricity from well-insulated detectors came a subject of great importance for modern science: the detection of a so-called `radiation' coming from not just beyond the Earth's atmosphere but from deep cosmic space. Furthermore, a radiation of energy density rivalling that of starlight. Our goal is to examine the history of the subject from the period of `pre-discovery' in the years from 1900 to 1912, through the discovery itself up to the 1940's when particle physics was continued with accelerators. The crucial role of `new techniques', principally the Wulf electrometer and the Wilson cloud chamber and their use in precission studies by Hess, Kolhörster, Anderson and Blackett are described. The arguments about the veracity of Hess's claim for an extra-terrestrial origin are included, as well as the developments leading to the inspired discovery of the positron and the muon. The question of `origin' is also examined, from the contention by Hess that the Sun was not responsible, to the idea - still held - that supernovae are involved.

Walter, M.; Wolfendale, A. W.

2012-08-01

283

A general scheme for multiparty controlled quantum teleportation of an arbitrary N-particle state  

Microsoft Academic Search

There is much interest in the multiparty quantum communications where quantum teleportation using high dimensional entangled quantum channel is one of the promising tools. In this paper, we propose a more general scheme for M-party controlled teleportation of an arbitrary N-particle quantum state using N-1 identical Einstein-Podolsky-Rosen pairs and one (M+2)-particle Greenberger-Horne-Zeilinger state together as quantum channel. Based on which

Ye Jun; Yue Li; Yu Liu; Sha Hua

2008-01-01

284

Particle Physics Aspects of Antihydrogen Studies with ALPHA at CERN  

Microsoft Academic Search

We discuss aspects of antihydrogen studies, that relate to particle physics ideas and techniques, within the context of the ALPHA experiment at CERN's Antiproton Decelerator facility. We review the fundamental physics motivations for antihydrogen studies, and their potential physics reach. We argue that initial spectroscopy measurements, once antihydrogen is trapped, could provide competitive tests of CPT, possibly probing physics at

M. C. Fujiwara; G. B. Andresen; W. Bertsche; P. D. Bowe; C. C. Bray; E. Butler; C. L. Cesar; S. Chapman; M. Charlton; J. Fajans; R. Funakoshi; D. R. Gill; J. S. Hangst; W. N. Hardy; R. S. Hayano; M. E. Hayden; A. J. Humphries; R. Hydomako; M. J. Jenkins; L. V. Jørgensen; L. Kurchaninov; W. Lai; R. Lambo; N. Madsen; P. Nolan; K. Olchanski; A. Olin; A. Povilus; P. Pusa; F. Robicheaux; E. Sarid; S. Seif El Nasr; D. M. Silveira; J. W. Storey; R. I. Thompson; D. P. van der Werf; L. Wasilenko; J. S. Wurtele; Y. Yamazaki

2008-01-01

285

Particle Physics Aspects of Antihydrogen Studies with ALPHA at CERN  

Microsoft Academic Search

We discuss aspects of antihydrogen studies, that relate to particle physics ideas and techniques, within the context of the ALPHA experiment at CERN's Antiproton Decelerator facility. We review the fundamental physics motivations for antihydrogen studies, and their potential physics reach. We argue that initial spectroscopy measurements, once antihydrogen is trapped, could provide competitive tests of CPT, possibly probing physics at

M. C. Fujiwara; G. B. Andresen; W. Bertsche; P. D. Bowe; C. C. Bray; E. Butler; C. L. Cesar; S. Chapman; M. Charlton; J. Fajans; R. Funakoshi; D. R. Gill; J. S. Hangst; W. N. Hardy; R. S. Hayano; A. J. Humphries; R. Hydomako; M. J. Jenkins; L. V. Jørgensen; L. Kurchaninov; W. Lai; R. Lambo; N. Madsen; P. Nolan; K. Olchanski; A. Olin; A. Povilus; P. Pusa; F. Robicheaux; E. Sarid; S. Seif; D. M. Silveira; J. W. Storey; R. I. Thompson; D. P. van der Werf; L. Wasilenko; J. S. Wurtele; Y. Yamazaki

2009-01-01

286

Bethe Ansatz Cluster Expansion Method for Quantum Integrable Particle Systems  

NASA Astrophysics Data System (ADS)

Presented is a method, which we call Bethe ansatz cluster expansion (BACE) method, to investigate statistical mechanics of quantum integrable systems. By use of only the Bethe ansatz equation, n-particle partition functions are exactly calculated. From the expression for the partition function, the n-particle cluster integrals are derived. The results completely agree with those of the thermal Bethe ansatz (TBA) by Yang and Yang. Thus, the BACE method directly proves the validity of the TBA. Partition theory and graphical representation are used to make the presentation simple and transparent.

Kato, Go; Wadati, Miki

2004-05-01

287

Lyapunov control of a quantum particle in a decaying potential  

Microsoft Academic Search

A Lyapunov-based approach for the trajectory generation of an N-dimensional Schrödinger equation in whole RN is proposed. For the case of a quantum particle in an N-dimensional decaying potential the convergence is precisely analyzed. The free system admitting a mixed spectrum, the dispersion through the absolutely continuous part is the main obstacle to ensure such a stabilization result. Whenever, the

Mazyar Mirrahimi

2009-01-01

288

Quantum molecular dynamics and particle production in heavy ion collisions  

NASA Astrophysics Data System (ADS)

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 discussed. The mechanisms of production processes are studied. The theoretical results are compared with the available experimental data.

Huang, S. W.; Faessler, A.; Li, G. Q.; Khoa, D. T.; Lehmann, E.; Matin, M. A.; Ohtsuka, N.; Puri, R. K.

289

Entropic Lower Bound for the Quantum Scattering of Spinless Particles  

Microsoft Academic Search

In this paper the angle-angular momentum entropic lower bound is proved by using Tsallis-like entropies and Riesz theorem for the quantum scattering of the spinless particles. Numerical estimations of the scattering entropies, as well as an experimental test of the state-independent entropic lower bound, are obtained by using the amplitude reconstruction from the available phase shift analyses for the pion-nucleus

D. B. Ion; M. L. D. Ion

1998-01-01

290

Physical model for the generation of ideal resources in multipartite quantum networking  

SciTech Connect

We propose a physical model for generating multipartite entangled states of spin-s particles that have important applications in distributed quantum information processing. Our protocol is based on a process where mobile spins induce the interaction among remote scattering centers. As such, a major advantage lies in the management of stationary and well-separated spins. Among the generable states, there is a class of N-qubit singlets allowing for optimal quantum telecloning in a scalable and controllable way. We also show how to prepare Aharonov, W, and Greenberger-Horne-Zeilinger states.

Ciccarello, F.; Zarcone, M. [CNISM and Dipartimento di Fisica e Tecnologie Relative, Universita degli Studi di Palermo, Viale delle Scienze, Edificio 18, I-90128 Palermo (Italy); Paternostro, M. [School of Mathematics and Physics, Queen's University, Belfast BT7 1NN (United Kingdom); Bose, S.; Browne, D. E. [Department of Physics and Astronomy, University College London, Gower Street, London WC1E 6BT (United Kingdom); Palma, G. M. [NANO-Istituto Nanoscienze-CNR and Dipartimento di Scienze Fisiche ed Astronomiche, Universita degli Studi di Palermo, Via Archirafi 36, I-90123 Palermo (Italy)

2010-09-15

291

Teaching Elementary Particle Physics, Part II  

ERIC Educational Resources Information Center

|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…

Hobson, Art

2011-01-01

292

One hundred years of quantum physics.  

PubMed

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

Kleppner, D; Jackiw, R

2000-08-11

293

Alpha Particle Physics Experiments in the Tokamak Fusion Test Reactor  

SciTech Connect

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

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

1998-12-14

294

Generation of quantum logic operations from physical Hamiltonians  

SciTech Connect

We provide a systematic analysis of the physical generation of single- and two-qubit quantum operations from Hamiltonians available in various quantum systems for scalable quantum information processing. We show that generation of single-qubit operations can be transformed into a steering problem on the Bloch sphere, which represents all R{sub z}-equivalence classes of single-qubit operations, whereas the two-qubit problem can be generally transformed into a steering problem in a tetrahedron representing all the local-equivalence classes of two-qubit operations (the Weyl chamber). We use this approach to investigate several physical examples for the generation of two-qubit operations. The steering approach provides useful guidance for the realization of various quantum computation schemes.

Zhang Jun [Department of Chemistry and Pitzer Center for Theoretical Chemistry, University of California, Berkeley, California 94720 (United States); Department of Electrical Engineering and Computer Sciences, University of California, Berkeley, California 94720 (United States); Whaley, K. Birgitta [Department of Chemistry and Pitzer Center for Theoretical Chemistry, University of California, Berkeley, California 94720 (United States)

2005-05-15

295

The Oxford Questions on the foundations of quantum physics  

PubMed Central

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.

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

2013-01-01

296

Heuristic classification of physical theories based on quantum correlations  

NASA Astrophysics Data System (ADS)

Taking quantum formalism as a point of reference and connection, we explore the various possibilities that arise in the construction of physical theories. Analyzing the distinct physical phenomena that each of them may describe, we introduce the different types of theories that correspond to these physical phenomena. A hierarchical classification of the offered theories, based on the degree of correlation between dichotomic observables in bipartite systems, as quantified by a Bell-type inequality, is finally proposed as a conclusion.

Ferrero, M.; Sánchez-Gómez, J. L.

2013-06-01

297

The Quark Machines: How Europe Fought the Particle Physics War  

Microsoft Academic Search

Gordon Fraser's agressive subtitle How Europe Fought the Particle Physics War suggests a battle for domination. In fact, his book provides a carefully researched and accurate account of the development of particle physics and its associated accelerators on both sides of the Atlantic, though with rather less attention to the role of the former Soviet Union. In terms of discoveries,

J D Dowell

1998-01-01

298

Quantum Hall physics with photons and its application  

NASA Astrophysics Data System (ADS)

Phenomena associated with the topological properties of physical systems can be naturally robust against perturbations. This robustness is exemplified by quantized conductance and edge state transport in the quantum Hall and quantum spin Hall effects. Here we demonstrate how quantum spin Hall Hamiltonians can be simulated with linear optical elements using a network of coupled resonator optical waveguides (CROW) in two dimensions. Key features of quantum Hall systems, including the characteristic Hofstadter butterfly and robust edge state transport, can be obtained in such systems. As a specific application, we show that topological protection can be used to improve the performance of optical delay lines and to overcome some limitations related to disorder in photonic technologies. Furthermore, the addition of an optical non-linearity to our proposed system leads to the possibility of implementing a fractional quantum Hall state of photons, where phenomenon such as fractional statistics may be observable.

Hafezi, Mohammad

2012-02-01

299

The Quantum Boltzmann Equation in Semiconductor Physics  

Microsoft Academic Search

The quantum Boltzmann equation, or Fokker-Planck equation, has been used to\\u000asuccessfully explain a number of experiments in semiconductor optics in the\\u000apast two decades. This paper reviews some of the developments of this work,\\u000aincluding models of excitons in bulk materials, electron-hole plasmas, and\\u000apolariton gases.

D. W. Snoke

2010-01-01

300

Quantum physics of simple optical instruments  

Microsoft Academic Search

Simple optical instruments are linear optical networks where the incident light modes are turned into equal numbers of outgoing modes by linear transformations. For example, such instruments are beam splitters, multiports, interferometers, fibre couplers, polarizers, gravitational lenses, parametric amplifiers, phase-conjugating mirrors and also black holes. The paper develops the quantum theory of simple optical instruments and applies the theory to

Ulf Leonhardt

2003-01-01

301

Precision observables for particle physics experiments  

NASA Astrophysics Data System (ADS)

The objective of this thesis is to develop tools for interpretation of the upcoming particle physics experiments. We implement and test Optimal Jet Finder (OJF), a jet finding algorithm that is based on the global energy flow in the event. OJF is infrared and collinear safe and resolves overlapping jets dynamically. The shapes of jets are determined dynamically and are not geometrical cones. However, they are more regular than those resulting from k?, which should facilitate detector calibration of OJF. We compare the statistical uncertainties of the W-boson mass when using three different jet finding algorithms: k? . JADE, and OJF. We find that OJF gives the same accuracy as k ? but is faster than k? if a large number of calorimeter cells is analyzed. We present the details of FORTRAN 77 and object-oriented C++ implementations of OJF. We calculate the rate of the lepton flavour violating mu ? e + gamma decay in a particular Grand Unification SO(10) model by Albright and Barr. We assume the Constrained Minimal Supersymmetric Standard Model framework. We interpret the results in view of the recent cosmological observations from Wilkinson Microwave Anisotropy Probe. We find that the SO(10) model is consistent with the experimental limits on the mu ? e + gamma branching ratio over a large volume of the supersymmetric parameter space. However, if the branching ratio is further constrained by the MEG experiment, carried out in the Paul Scherrer Institute, below 10 -13, the available volume of the parameter space will be significantly reduced. We calculate the QED suppression of the rate of the lepton flavour violating mu ? e + gamma decay. The result, does not depend on the details of the mechanism that, is responsible for the lepton flavour violation, except for the mass scale that enters the final expression. If this mass scale is between 100 and 1000 GeV, the numerical value of the decrease in the decay rate is between 12% and 17%. If the rare muon decay is observed in the MEG experiment, our result will enhance the precision with which the parameters of the new physics models responsible for this decay can be extracted.

Jankowski, Ernest

302

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

Microsoft Academic Search

In standard physics quantum field theory is based on a flat vacuum space-time. This quantum field theory predicts a nonzero cosmological constant. Hence the gravitational field equations do not admit a flat vacuum space-time. This dilemma is resolved using the units covariant gravitational field equations. This paper shows that the field equations admit a flat vacuum space-time with nonzero cosmological

Peter J. Adams

1983-01-01

303

Quantum Physics made Relatively Simple: Three Lectures by Hans Bethe  

NSDL National Science Digital Library

The site contains three lectures of Professor Hans Bethe. The lecture topics concern the development of quantum theory; relations between the exciting theoretical/experimental breakthrough; and how quantum theory forced discussion of issues such as determinism, physical observables, and action-at-a-distance. Professor Hans delivered these three lectures in 1999 to his neighbors at the Kendal of Ithaca retirement community (near Cornell University in Ithaca, NY).

Bethe, Hans

2006-07-22

304

Introduction and Survey I - Concepts from particle physics  

NASA Astrophysics Data System (ADS)

An account is given of those concepts from elementary particle physics which play a role in astrophysics. These concepts encompass spontaneous symmetry breaking, such topologically stable 'defect' field configurations as solitons and instantons, the transitions between different ground states, and the restoration of spontaneously brokem symmetries at finite temperatures. Attention is given to grand unified theories, such dark-matter candidates from particle physics as neutrinos with nonvanishing mass, and novel particles suggested by the development of concepts in string theory.

Breitenlohner, Peter

1989-06-01

305

Quantum nanoelectromechanics with electrons, quasi-particles and Cooper pairs: effective bath descriptions and strong feedback effects  

Microsoft Academic Search

Using a quantum-noise approach, we discuss the physics of both normal metal and superconducting single-electron transistors (SSETs) coupled to mechanical resonators. Particular attention is paid to the regime where transport occurs via incoherent Cooper-pair tunnelling (either via the Josephson quasi-particle (JQP) or double JQP (DJQP) process). We show that, surprisingly, the back-action of tunnelling Cooper pairs (or superconducting quasi-particles) can

Aashish A. Clerk; Steven Bennett

2005-01-01

306

Two decades of Mexican particle physics at Fermilab  

SciTech Connect

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

Roy Rubinstein

2002-12-03

307

Quantum Hall Physics Equals Noncommutative Field Theory  

Microsoft Academic Search

In this note, we study a matrix-regularized version of non-commutative U(1) Chern- Simons theory proposed recently by Polychronakos. We determine a complete minimal basis of exact wavefunctions for the theory at arbitrary level k and rank N and show that these are in one-to-one correspondence with Laughlin-type wavefunctions describing excitations of a quantum Hall droplet composed of N electrons at

Simeon Hellerman; Mark Van Raamsdonk

308

Quantum Shuttle: Physics of a Numerical Challenge  

Microsoft Academic Search

Shuttle devices are a class of nanoelectromechanical systems generically described as movable single electron transistors.\\u000a They exhibit an electromechanical instability from the standard tunnelling regime to the shuttling regime in which the quantum\\u000a dot oscillates and transfer one electron per cycle. I present a theory for the device in which both the electrical and mechanical\\u000a degrees of freedom are quantized.

Andrea Donarini

309

Synthesis of quantum chromodynamics and nuclear physics  

SciTech Connect

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.

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

1980-08-01

310

Progress Report 1985/86 of the Institute for Theoretical Physics, Technical University of Vienna, Austria.  

National Technical Information Service (NTIS)

Short descriptions of projects in the fields: 1) theoretical solid state physics, 2) statistical physics, 3) mathematical physics, 4) quantum mechanics, 5) quantum optics, 6) elementary particles physics, 7) quantum field theory and gauge theory and a lis...

J. Hafner

1986-01-01

311

PARTICLE PHYSICS: CERN Collider Glimpses Supersymmetry--Maybe.  

PubMed

Last week, particle physicists at the CERN laboratory in Switzerland announced that by smashing together matter and antimatter in four experiments, they detected an unexpected effect in the sprays of particles that ensued. The anomaly is subtle, and physicists caution that it might still be a statistical fluke. If confirmed, however, it could mark the long-sought discovery of a whole zoo of new particles--and the end of a long-standing model of particle physics. PMID:17750395

Seife, C

2000-07-14

312

Quantum Mechanics for Beginning Physics Students  

ERIC Educational Resources Information Center

|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…

Schneider, Mark B.

2010-01-01

313

High-P Physics with Identified Particles  

NASA Astrophysics Data System (ADS)

The suppression of high-P particles in heavy ion collisions was one of the key discoveries at the Relativistic Heavy Ion Collider. This is usually parameterized by the average rate of momentum-transfer squared to this particle, q?. Here we argue that measurements of identified particles at high P can lead to complementary information about the medium. The leading particle of a jet can change its identity through interactions with the medium. Tracing such flavor conversions could allow us to constrain the mean free path. Here we review the basic concepts of flavor conversions and discuss applications to particle ratios and elliptic flow. We make a prediction that strangeness is enhanced at high P at RHIC energies while its elliptic flow is suppressed.

Fries, Rainer J.; Liu, Wei

2009-11-01

314

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

ERIC Educational Resources Information Center

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

Henry, Richard C.

1982-01-01

315

Particle physics meets cosmology - The search for decaying neutrinos  

NASA Astrophysics Data System (ADS)

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.

Henry, R. C.

1982-11-01

316

WHAT ARE THE HIDDEN QUANTUM PROCESSES BEHIND NEWTON'S LAWS? EMQG, CA Theory, Quantum Inertia, and Newtonian Physics  

Microsoft Academic Search

We investigate the hidden quantum processes that are responsible for Newton's laws of motion and Newton's universal law of gravity. We apply Electro-Magnetic Quantum Gravity or EMQG (ref. 1) to investigate Newtonian classical physics. EQMG is a quantum gravity theory that is manifestly compatible with Cellular Automata (CA) theory, a new paradigm for physical reality. EMQG is also based on

Tom Ostoma; Mike Trushyk

317

Particle Swarm Optimization with Quantum Infusion for the design of digital filters  

Microsoft Academic Search

In this paper, particle swarm optimization with quantum infusion (PSO-QI) has been applied for the design of digital filters. In PSO-QI, Global best (gbest) particle (in PSO star topology) obtained from particle swarm optimization is enhanced by doing a tournament with an offspring produced by quantum behaved PSO, and selecting the winner as the new gbest. Filters are designed based

Bipul Luitel; Ganesh Kumar Venayagamoorthy

2008-01-01

318

Quantum Field Theory of Particles with Both Electric and Magnetic Charges  

Microsoft Academic Search

The quantum field theory of particles with both electric and magnetic charges is developed as an obvious extension of Schwinger's quantum field theory of particles with either electric or magnetic charge. Two new results immediately follow. The first is the chiral equivalence theorem which states the unitary equivalence of the Hamiltonians describing the system of particles with electric and magnetic

Daniel Zwanziger

1968-01-01

319

The geometric phase in quantum physics  

SciTech Connect

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

Bohm, A.

1993-03-01

320

The bondons: the quantum particles of the chemical bond.  

PubMed

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

Putz, Mihai V

2010-10-28

321

Quantum Processes and Dynamic Networks in Physical and Biological Systems.  

NASA Astrophysics Data System (ADS)

Quantum theory since its earliest formulations in the Copenhagen Interpretation has been difficult to integrate with general relativity and with classical Newtonian physics. There has been traditionally a regard for quantum phenomena as being a limiting case for a natural order that is fundamentally classical except for microscopic extrema where quantum mechanics must be applied, more as a mathematical reconciliation rather than as a description and explanation. Macroscopic sciences including the study of biological neural networks, cellular energy transports and the broad field of non-linear and chaotic systems point to a quantum dimension extending across all scales of measurement and encompassing all of Nature as a fundamentally quantum universe. Theory and observation lead to a number of hypotheses all of which point to dynamic, evolving networks of fundamental or elementary processes as the underlying logico-physical structure (manifestation) in Nature and a strongly quantized dimension to macroscalar processes such as are found in biological, ecological and social systems. The fundamental thesis advanced and presented herein is that quantum phenomena may be the direct consequence of a universe built not from objects and substance but from interacting, interdependent processes collectively operating as sets and networks, giving rise to systems that on microcosmic or macroscopic scales function wholistically and organically, exhibiting non-locality and other non -classical phenomena. The argument is made that such effects as non-locality are not aberrations or departures from the norm but ordinary consequences of the process-network dynamics of Nature. Quantum processes are taken to be the fundamental action-events within Nature; rather than being the exception quantum theory is the rule. The argument is also presented that the study of quantum physics could benefit from the study of selective higher-scale complex systems, such as neural processes in the brain, by virtue of mathematical and computational models that may be transferred from the macroscopic domain to the microscopic. A consequence of this multi-faceted thesis is that there may be mature analytical tools and techniques that have heretofore not been adequately recognized for their value to quantum physics. These may include adaptations of neural networks, cellular automata, chaotic attractors, and parallel processing systems. Conceptual and practical architectures are presented for the development of software and hardware environments to employ massively parallel computing for the modeling of large populations of dynamic processes.

Dudziak, Martin Joseph

322

Cosmology and particle physics - a general review  

SciTech Connect

The various stages in the evolution of the universe from approximately 0.0001 sec to approximately more than 100,000 years are discussed. The use of quantum gravity, the Kaluza (1921) and Klein (1926) theories, and supersymmetry to study the gravitational interactions during the Planck epoch is examined. Examples of the effect of exponential expansion due to a supercooled phase transition (inflation) are presented. The big bang baryosynthesis and nucleosynthesis hypotheses are reviewed. 86 references.

Olive, K.A.

1986-01-01

323

Relativistic models in nuclear and particle physics  

SciTech Connect

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

Coester, F.

1988-01-01

324

Particle escapes in an open quantum network via multiple leads  

SciTech Connect

Quantum escape of a particle from an end of a one-dimensional finite region to N semi-infinite leads is discussed from a scattering theory approach. Depending on the potential barrier amplitude at the junction, the probability P(t) for a particle to remain in the finite region at time t shows two different decay behaviors at long times; one is proportional to N{sup 2}/t{sup 3} and another is proportional to 1/(N{sup 2}t). In addition, the velocity V(t) for a particle to leave the finite region, defined from a probability current of the particle position, decays asymptotically as a power of time {approx}1/t, independent of the number of leads and the initial wave function. For a finite time, the probability P(t) decays exponentially in time with a smaller decay rate for a greater number of leads, and the velocity V(t) shows a time oscillation whose amplitude is larger for a greater number of leads. Particle escapes from the both ends of a finite region to multiple leads are also discussed using a different boundary condition.

Taniguchi, Tooru; Sawada, Shin-ichi [School of Science and Technology, Kwansei Gakuin University, 2-1 Gakuen, Sanda City (Japan)

2011-12-15

325

Time evolution of decay of two identical quantum particles  

SciTech Connect

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

Garcia-Calderon, Gaston; Mendoza-Luna, Luis Guillermo [Instituto de Fisica, Universidad Nacional Autonoma de Mexico, Apartado Postal 20-364, Mexico 01000, Distrito Federal (Mexico)

2011-09-15

326

On the origin of the quantum rules for identical particles  

NASA Astrophysics Data System (ADS)

We present a proof of the Symmetrization Postulate for the special case of noninteracting, identical particles. The proof is given in the context of the Feynman formalism of Quantum Mechanics, and builds upon the work of Goyal, Knuth and Skilling [1], which shows how to derive Feynman's rules from operational assumptions concerning experiments. Our proof is inspired by an attempt to derive this result due to Tikochinsky [2], but substantially improves upon his argument, by clarifying the nature of the subject matter, by improving notation, and by avoiding strong, abstract assumptions such as analyticity.

Neori, Klil H.; Goyal, Philip

2013-08-01

327

Time fluctuations in isolated quantum systems of interacting particles  

NASA Astrophysics Data System (ADS)

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

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

2013-09-01

328

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

ERIC Educational Resources Information Center

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

Gerstein, Lawrence H.; Bennett, Matt

1999-01-01

329

THE CENTENARY OF NIELS BOHR: Niels Bohr and quantum physics  

Microsoft Academic Search

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

A. B. Migdal

1985-01-01

330

Open Source Physics Curricular Material for Quantum Mechanics  

Microsoft Academic Search

Much of the difficulty in learning advanced concepts in quantum mechanics comes from trying to visualize abstract problems. This article addresses the situation with interactive curricular material created as part of the open source physics project. In particular, the authors focus on the measurement and time evolution of two-state superpositions in the context of bound states and spin.

Mario Belloni; Wolfgang Christian; Douglas Brown

2007-01-01

331

Noncommutative analysis and quantum physics I. Quantities, ensembles and states  

Microsoft Academic Search

A unified conceptual foundation of classical and quantum physics is given, free of undefined terms. Ensembles are defined by extending the `probability via expectation' approach of Whittle to noncommuting quantities. This approach carries no connotations of unlimited repeatability; hence it can be applied to unique systems such as the universe. Precise concepts and traditional results about complementarity, uncertainty and nonlocality

Arnold Neumaier

2000-01-01

332

Learning Introductory Quantum Physics: Sensorimotor experiences and mental models  

Microsoft Academic Search

This paper reports a cross-sectional study of Taiwanese physics students' understanding of subatomic phenomena that are explained by quantum mechanics. The study uses students' explanations of their answers to items in a questionnaire as a proxy for students' thinking. The variation in students' explanations is discussed as is the development in the way in which students link different concepts. A

Martin Monk; Richard Duschl

2005-01-01

333

Noncommutative analysis and quantum physics I. States and ensembles  

Microsoft Academic Search

In this sequence of papers, noncommutative analysis is used to give a consistent axiomatic approach to a unified conceptual foundation of classical and quantum physics. The present Part I defines the concepts of observables, states and ensembles, clarifies the logical relations and operations for them, and shows how they give rise to dynamics and probabilities. States are identified with maximal

Arnold Neumaier

1999-01-01

334

Device physics of quantum-well heterostructure MI3SFET's  

Microsoft Academic Search

A quantum-well heterostructure FET that is undoped except for a thin layer beneath the well and is fabricated in an ion-implanted self-aligned geometry is examined in experiments and computer simulations. Key aspects of the physics of this device, which relate to channel access, charge control, and deep-level trapping, are described.

R. A. Kiehl; D. J. Frank; S. L. Wright; J. H. Magerlein

1987-01-01

335

QUANTUM-LIKE CORRECTIONS AND TOMOGRAPHY IN BEAM PHYSICS  

Microsoft Academic Search

A novel tomographic approach to charged-particle beam physics is suggested in the framework of Thermal Wave Model (TWM). It is shown that the particle beam transport in the phase-space can be described in terms of a marginal distribution which has the features of a classical proba- bility distribution, including its positive definiteness. It is shown that the above marginal distribution

R. Fedele; P. N. Lebedev

336

Quantum particle statistics on the holographic screen leads to modified Newtonian dynamics  

NASA Astrophysics Data System (ADS)

Employing a thermodynamic interpretation of gravity based on the holographic principle and assuming underlying particle statistics, fermionic or bosonic, for the excitations of the holographic screen leads to modified Newtonian dynamics (MOND). A connection between the acceleration scale a0 appearing in MOND and the Fermi energy of the holographic fermionic degrees of freedom is obtained. In this formulation the physics of MOND results from the quantum-classical crossover in the fermionic specific heat. However, due to the dimensionality of the screen, the formalism is general and applies to two-dimensional bosonic excitations as well. It is shown that replacing the assumption of the equipartition of energy on the holographic screen by a standard quantum-statistical-mechanics description wherein some of the degrees of freedom are frozen out at low temperatures is the physical basis for the MOND interpolating function ?˜. The interpolating function ?˜ is calculated within the statistical mechanical formalism and compared to the leading phenomenological interpolating functions, most commonly used. Based on the statistical mechanical view of MOND, its cosmological implications are reinterpreted: the connection between a0 and the Hubble constant is described as a quantum uncertainty relation; and the relationship between a0 and the cosmological constant is better understood physically.

Pazy, E.; Argaman, N.

2012-05-01

337

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

SciTech Connect

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.

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

338

Understanding probabilistic interpretations of physical systems: A prerequisite to learning quantum physics  

Microsoft Academic Search

Probability plays a critical role in making sense of quantum physics, but most science and engineering undergraduates have very little experience with the topic. A probabilistic interpretation of a physical system, even at a classical level, is often completely new to them, and the relevant fundamental concepts such as the probability distribution and probability density are rarely understood. To address

Lei Bao; Edward F. Redish

2002-01-01

339

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

ERIC Educational Resources Information Center

|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)|

Bao, Lei; Redish, Edward F.

2002-01-01

340

Physical properties of soft repulsive particle fluids.  

PubMed

Molecular dynamics computer simulation has been applied to inverse power or soft-sphere fluids, in which the particles interact through the soft-sphere pair potential, phi(r) = epsilon(sigma/r)(n), where n measures the steepness or stiffness of the potential, and epsilon and sigma are a characteristic energy and distance, respectively. The focus of the study is on very soft particles with n values down to 4 considered, at densities up to and along the fluid-solid co-existence density. It is shown that in the soft-particle limit the local structure is dominated by the lengthscale associated with the average nearest neighbour distance of a random structure, which is proportional, variantrho(-1/3) and increasingly only very weakly dependent on n. This scaling is also manifest in the behaviour of the average energy per particle with density. The self-diffusion coefficient and shear viscosity are computed along the fluid-solid co-existence line as a function of n, for the first time. The product Deta(s) steadily increases with softness for n < 10, whereas the modified Stokes-Einstein relationship of Zwanzig, Deta(s)/rho(1/3), where rho is the number density, is within statistics constant over the same softness range. This is consistent with our observation that the static properties are determined by a characteristic lengthscale (i.e., l) which is proportional, variantrho(-1/3) in the soft-particle limit. The high frequency elastic moduli of these fluids are examined, which reveals that the mechanical properties become more 'rubbery' as the particles get softer. PMID:17957313

Heyes, D M; Bra?ka, A C

2007-08-29

341

The role of supersymmetry phenomenology in particle physics  

SciTech Connect

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

Wells, James D.

2000-12-14

342

Elementary particle physics and the superconducting super collider.  

PubMed

The present status and future prospects of elementary particle physics are reviewed, and some of the scientific questions that motivate the construction of a major new accelerator complex in the United States are summarized. PMID:17833313

Quigg, C; Schwitters, R F

1986-03-28

343

Quarks and Leptones: An Introductory Course in Modern Particle Physics  

Microsoft Academic Search

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.

Francis Halzen; Alan D. Martin

1984-01-01

344

The Physical Principles of Quantum Gyroscopy.  

National Technical Information Service (NTIS)

The report describes some of the physical phenomena which can be used as the basis for creation of devices sensitive to ratation. In all of the cases that are analyzed, this purpose has been achieved using sets of mechanical or magnetic properties of atom...

N. M. Pomerantsev G. V. Skrotskii

1970-01-01

345

Elementary particle physics and high energy phenomena  

SciTech Connect

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).

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

346

Pixel detectors for particle physics and imaging applications  

Microsoft Academic Search

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 X-ray 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

N. Wermes

2003-01-01

347

Thermodynamic anomaly of the free damped quantum particle: the bath perspective  

NASA Astrophysics Data System (ADS)

A possible definition of the specific heat of open quantum systems is based on the reduced partition function of the system. For a free damped quantum particle, it has been found that under certain conditions, this specific heat can become negative at low temperatures. In contrast to the conventional approaches focusing on the system degree of freedom, here we concentrate on the changes induced in the environment when the system is coupled to it. Our analysis is carried out for an Ohmic environment consisting of harmonic oscillators and allows to identify the mechanism by which the specific heat becomes negative. Furthermore, the formal condition for the occurrence of a negative specific heat is given a physical interpretation in terms of the total mass of bath oscillators and the system mass.

Ingold, G.-L.

2012-01-01

348

Qps Transport and Energetic Particle Physics  

NASA Astrophysics Data System (ADS)

The transport and confinement of compact quasi-poloidal stellarators (QPS) have been evaluated using computational tools that accurately model the strong toroidal coupling characteristic of the magnetic field structure at low aspect ratios (A < 3). Core neoclassical transport issues of interest include the perpendicular fluxes of particles and energy, bootstrap current, self-consistent ambipolar states, and flow damping viscosity. These topics have been addressed using both local diffusive models (such as the DKES and NEO codes) and non-local particle-based Monte Carlo techniques. Energy lifetime estimates will be made for QPS devices and comparisons will be made between the different models. Energetic particle confinement is generally more sensitive to the structure of |B| due to the lower collisionalities. Particle based codes (DELTA5D) can follow the evolution of fast ion populations (alphas, ICRF tails) through slowing-down timescales, allowing estimates of heating efficiency. The excitation of Alfvén (AE) instabilities by antennas/fast ions in 3D systems has been addressed using a high-resolution calculation of the AE continua and mode structures.

Spong, D. A.; Berry, L. A.; Hirshman, S. P.; Lyon, J. F.; Mikkelsen, D.; Sanchez, R.

2002-11-01

349

The Knight of the Quantum: On the Contribution of D.I. Blokhintsev to Quantum Physics1  

Microsoft Academic Search

A concise survey of the contribution of D.I. Blokhintsev to the quantum physics, including solid state physics, physics of metals, surface physics, statistical physics and optics is given. These achievements have been considered in the context of modern development of these fields of physics. The name of Corresponding Member of the Academy of Sciences of the USSR D. I. Blokhintsev

A. L. Kuzemsky

350

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

ERIC Educational Resources Information Center

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

Wagoner, Robert; Goldsmith, Donald

1983-01-01

351

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

ERIC Educational Resources Information Center

|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…

Farmelo, Graham

1992-01-01

352

EDITORIAL: Focus on Dark Matter and Particle Physics  

Microsoft Academic Search

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

Elena Aprile; Stefano Profumo

2009-01-01

353

Guide to Experimental Elementary Particle Physics Literature 1994-1998.  

National Technical Information Service (NTIS)

This is an indexed guide to experimental particle physics literature forthe years 1994-1998. About 4100 papers are indexed by Beam/Target/Momentum, Reaction/Momentum/Data-Descriptor, Particle/Decay,Accelerator/ Experiment/Detector. All indices are cross-r...

A. P. Jerusalimov B. Armstrong B. B. Filimonov B. V. Polishchuk D. E. Groom E. A. Razuvaev G. A. Arutyunyants O. V. Zenin P. S. Gee R. M. Barnett S. B. Lugovsky S. I. Striganov S. M. Kiselev S. R. Slabospitsky T. G. Trippe V. Ezhela V. S. Lugovsky W. Yao Y. G. Stroganov

1999-01-01

354

Energetic particle physics with applications in fusion and space plasmas  

SciTech Connect

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.

Cheng, C.Z.

1997-05-01

355

Resource Letter HEPP-1: History of elementary-particle physics  

NASA Astrophysics Data System (ADS)

This Resource Letter provides a guide to literature on the history of modern elementary-particle physics. Histories that treat developments from the 1930s through the 1980s are focused on and a sampling is included of the historiography covering the period c. 1890-1930, the prehistory of elementary-particle physics as a discipline. Also included are collections of scientific papers, which might be especially valuable to individuals who wish to undertake historical research on particular scientists or subfields of elementary-particle physics. The introduction presents some statistical data and associated references for elementary-particle physics and surveys historiographical approaches and issues that are represented in historical accounts in the bibliography. All references are assigned a rating of E (Elementary), I (Intermediate), or A (Advanced) based on their technical or conceptual difficulty or their appropriateness for a person attempting a graduated study of the history of modern particle physics. That is, items labeled E are suitable for the layman or would be fundamental to a beginning exploration of the history of particle physics, whereas items labeled A are technically demanding (mathematically, historiographically, or philosophically) or would be most appropriate for specialized or advanced examinations of various topics.

Hovis, R. Corby; Kragh, Helge

1991-09-01

356

A derivation of quantum theory from physical requirements  

NASA Astrophysics Data System (ADS)

Quantum theory is usually formulated by postulating the mathematical structure and representation of states, transformations, and measurements. The general physical consequences that follow (like violation of Bell-type inequalities, the possibility of performing state tomography with local measurements, or factorization of integers in polynomial time) come as theorems which use the postulates as premises. In this work, this procedure is reversed: we impose five simple physical requirements, and this suffices to single out quantum theory and derive its mathematical formalism uniquely. This is more similar to the usual formulation of special relativity, where two simple physical requirements ---the principles of relativity and light speed invariance--- are used to derive the mathematical structure of Minkowski space-time and its transformations.

Mueller, Markus; Masanes, Lluis

2011-03-01

357

A derivation of quantum theory from physical requirements  

NASA Astrophysics Data System (ADS)

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

Masanes, Lluís; Müller, Markus P.

2011-06-01

358

Entanglement of indistinguishable particles in condensed-matter physics  

Microsoft Academic Search

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

Mark R. Dowling; Andrew C. Doherty; Howard M. Wiseman

2006-01-01

359

The quantum physics of chronology protection  

Microsoft Academic Search

This is a brief survey of the current status of Stephen Hawking's\\u000a``chronology protection conjecture''. That is: ``Why does nature abhor a time\\u000amachine?'' I'll discuss a few examples of spacetimes containing ``time\\u000amachines'' (closed causal curves), the sorts of peculiarities that arise, and\\u000athe reactions of the physics community. While pointing out other possibilities,\\u000athis article concentrates on the

Matt Visser

2002-01-01

360

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

PubMed Central

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.

Putz, Mihai V.

2010-01-01

361

Superfluid Helium 3: Link Between Condensed Matter Physics and Particle Physics  

Microsoft Academic Search

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

D. Vollhardt; P. Woelfle

2000-01-01

362

Structural physical approximations of unphysical maps and generalized quantum measurements  

SciTech Connect

We investigate properties of the structural physical approximation (SPA) of the partial transposition map recently introduced by Horodecki and Ekert [Phys. Rev. Lett. 89, 127902 (2002)]. We focus on the case of two-qubit states and show that in this case the map has the structure of a generalized quantum measurement followed by the preparation of a suitable output state. We also introduce SPA for a map that transforms two copies of density matrix of a single qubit onto a square of that matrix. We prove that also this map is essentially a generalized quantum measurement.

Fiurasek, Jaromir [Department of Optics, Palacky University, 17. listopadu 50, 77200 Olomouc (Czech Republic)

2002-11-01

363

Physical theories, eternal inflation, and the quantum universe  

NASA Astrophysics Data System (ADS)

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

Nomura, Yasunori

2011-11-01

364

Quantum Physics, Relativity, and Complex Spacetime: Towards a New Synthesis  

Microsoft Academic Search

The positivity of the energy in relativistic quantum mechanics implies that wave functions can be continued analytically to the forward tube T in complex spacetime. For Klein-Gordon particles, we interpret T as an extended (8D) classical phase space containing all 6D classical phase spaces as symplectic submanifolds. The evaluation maps $e_z: f\\\\to f(z)$ of wave functions on T are relativistic

Gerald Kaiser

2009-01-01

365

Efimov States in Nuclear and Particle Physics  

Microsoft Academic Search

Particles with resonant short-range interactions have universal properties that do not depend on the details of their structure or their interactions at short distances. In the three-body system, these properties include the existence of a geometric spectrum of three-body Efimov states and a discrete scaling symmetry, which leads to log-periodic dependence of observables on the scattering length. Similar universal properties

Hans-Werner Hammer; Lucas Platter

2010-01-01

366

Subbarrier Fusion Reactions and Many-Particle Quantum Tunneling  

NASA Astrophysics Data System (ADS)

Low-energy heavy-ion fusion reactions are governed by quantum tunneling through the Coulomb barrier formed by the strong cancellation of the repulsive Coulomb force with the attractive nuclear interaction between the colliding nuclei. Extensive experimental as well as theoretical studies have revealed that fusion reactions are strongly influenced by couplings of the relative motion of the colliding nuclei to several nuclear intrinsic motions. Heavy-ion subbarrier fusion reactions thus provide a good opportunity to address the general problem of quantum tunneling in the presence of couplings, which has been a popular subject in recent decades in many branches of physics and chemistry. Here, we review theoretical aspects of heavy-ion subbarrier fusion reactions from the viewpoint of quantum tunneling in systems with many degrees of freedom. Particular emphases are put on the coupled-channels approach to fusion reactions and the barrier distribution representation for multichannel penetrability. We also discuss an application of the barrier distribution method to elucidate the mechanism of the dissociative adsorption of H_2 molecules in surface science.

Hagino, K.; Takigawa, N.

2012-12-01

367

The Art and Science of Experimentation in Quantum Physics  

NASA Astrophysics Data System (ADS)

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

Plotnitsky, Arkady

2010-05-01

368

Black hole bombs and explosions: from astrophysics to particle physics  

NASA Astrophysics Data System (ADS)

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

Cardoso, Vitor

2013-11-01

369

J-PARC Status, Nuclear and Particle Physics  

SciTech Connect

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.

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

370

A graceful multiversal link of particle physics to cosmology  

Microsoft Academic Search

We work out a multiverse scenario whose physical characteristics enable us to advance the following conjecture: whereas the\\u000a physics of particles and fields is confined to live in the realm of the whole multiverse formed by finite-time single universes,\\u000a the physics of our observable universe must be confined to just one of the infinite number of universes where such a

P. F. González-Díaz; Prado Mart ´ õn Moruno; Artyom V. Yurov

2010-01-01

371

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

SciTech Connect

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

Not Available

1991-12-01

372

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

ERIC Educational Resources Information Center

|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;…

Rice, Charles V.; Giffin, Guinevere A.

2008-01-01

373

Quantum study of the halfium particle as a reference system in MQDT analysis of H2  

Microsoft Academic Search

In this paper, we introduce the halfium particle (Ha) as a new molecular reference system for the study of electronic states of molecular hydrogen. For this fictive quantum system, we solve the Schrödinger equation, calculate its Born-Oppenheimer adiabatic potential curves and define a set of Ha quantum defects. The comparison of Ha and standard H2 quantum defects, gives a new

Soumaya Bezzaouia; Mourad Telmini

2007-01-01

374

Experimental and theoretical particle physics. Final report  

SciTech Connect

A brief sketch of the accomplishments made in the past year is given for the following: {epsilon} expansion analysis of weak first-order transitions in the cubic anisotropy model; the non-Abelian Debye screening length beyond leading order; electric-magnetic duality and the heavy quark potential; ice water vapor interface; groups in cold dark matter simulations; Compton scattering on black body photons; nuclear reaction rates in a plasma; comparison of jets from electron-positron interactions and hadronic collisions; the energy-energy correlation in perturbation theory; CPT violation search in the kaon system; regularization of chiral gauge theories; dynamical supersymmetry breaking; electroweak baryogenesis; quenched chiral perturbation theory for heavy-light mesons; testing the chiral behavior of the hadron spectrum; hadron spectrum with Wilson fermions; quenched chiral perturbation theory for baryons; matrix elements of 4-fermion operators with quenched Wilson fermions; classical preheating and decoherence; reheating and thermalization in a simple scalar model; and from quantum field theory to hydrodynamics: transport coefficients and effective kinetic theory.

NONE

1996-07-09

375

Octonions, E6, and particle physics  

NASA Astrophysics Data System (ADS)

In 1934, Jordan et al. gave a necessary algebraic condition, the Jordan identity, for a sensible theory of quantum mechanics. All but one of the algebras that satisfy this condition can be described by Hermitian matrices over the complexes or quaternions. The remaining, exceptional Jordan algebra can be described by 3 × 3 Hermitian matrices over the octonions. We first review properties of the octonions and the exceptional Jordan algebra, including our previous work on the octonionic Jordan eigenvalue problem. We then examine a particular real, noncompact form of the Lie group E6, which preserves determinants in the exceptional Jordan algebra. Finally, we describe a possible symmetry-breaking scenario within E6: first choose one of the octonionic directions to be special, then choose one of the 2×2 submatrices inside the 3×3 matrices to be special. Making only these two choices, we are able to describe many properties of leptons in a natural way. We further speculate on the ways in which quarks might be similarly encoded.

Manogue, Corinne A.; Dray, Tevian

2010-11-01

376

A Pyramid Scheme for particle physics  

NASA Astrophysics Data System (ADS)

We introduce a new model, the Pyramid Scheme, of direct mediation of SUSY breaking, which is compatible with the idea of Cosmological SUSY Breaking (CSB). It uses the trinification scheme of grand unification and avoids problems with Landau poles in standard model gauge couplings. It also avoids problems, which have recently come to light [6], associated with rapid stellar cooling due to emission of the pseudo Nambu-Goldstone Boson (PNGB) of spontaneously broken hidden sector ``baryon" number. With a certain pattern of R-symmetry breaking masses, a pattern more or less required by CSB, the Pyramid Scheme leads to a dark matter candidate that decays predominantly into leptons, with cross sections compatible with a variety of recent observations [4]. The dark matter particle is not a thermal WIMP but a particle with new strong interactions, produced in the late decay of some other scalar, perhaps the superpartner of the QCD axion, with a reheat temperature in the TeV range. This is compatible with a variety of scenarios for baryogenesis, including some novel ones which exploit specific features of the Pyramid Scheme.

Banks, T.; Fortin, J.-F.

2009-07-01

377

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

SciTech Connect

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

Sen, Aditi; Sen, Ujjwal [ICFO-Institut de Ciencies Fotoniques, Mediterranean Technology Park, E-08860 Castelldefels (Barcelona) (Spain); Institut fuer Theoretische Physik, Universitaet Hannover, D-30167 Hannover (Germany); Gromek, Bartosz [Department of Theoretical Physics, University of Lodz, ul. Pomorska 149/153, PL-90236 Lodz (Poland); Bruss, Dagmar [Institut fuer Theoretische Physik III, Heinrich-Heine-Universitaet Duesseldorf, D-40225 Duesseldorf (Germany); Lewenstein, Maciej [Institut fuer Theoretische Physik, Universitaet Hannover, D-30167 Hannover (Germany); ICREA and ICFO-Institut de Ciencies Fotoniques, Mediterranean Technology Park, E-08860 Castelldefels (Barcelona) (Spain)

2007-02-15

378

Localization of a polymer in random media: relation to the localization of a quantum particle.  

PubMed

In this paper we consider in detail the connection between the problem of a polymer in a random medium and that of a quantum particle in a random potential. We are interested in a system of finite volume where the polymer is known to be localized inside a low minimum of the potential. We show how the end-to-end distance of a polymer that is free to move can be obtained from the density of states of the quantum particle using extreme value statistics. We give a physical interpretation to the recently discovered one-step replica-symmetry-breaking solution for the polymer [Phys. Rev. E 61, 1729 (2000)] in terms of the statistics of localized tail states. Numerical solutions of the variational equations for chains of different length are performed and compared with quenched averages computed directly by using the eigenfunctions and eigenenergies of the Schrödinger equation for a particle in a one-dimensional random potential. The quantities investigated are the radius of gyration of a free Gaussian chain, its mean square distance from the origin and the end-to-end distance of a tethered chain. The probability distribution for the position of the chain is also investigated. The glassiness of the system is explained and is estimated from the variance of the measured quantities. PMID:11414926

Shiferaw, Y; Goldschmidt, Y Y

2001-04-25

379

GENERAL: Quantum Secure Direct Communication Using Six-Particle Maximally Entangled States and Teleportation  

Microsoft Academic Search

The sender shares six-particle maximally entangled states as quantum channel with the receiver. If the quantum channel is secure, the sender performs projective measurements and tells the measurement outcome to the receiver. The receiver performs the unitary transformations and makes projective measurements on his particles to obtain the secret information. Using teleportation, the transmission of three-qubit secret information can be

Xiao-Ming Xiu; Li Dong; Ya-Jun Gao; Feng Chi

2009-01-01

380

Using Quantum Coherence to Enhance Gain in Atomic Physics  

NASA Astrophysics Data System (ADS)

Quantum coherence and interference effects in atomic and molecular physics have been extensively studied because of intriguing counterintuitive physics and potential important applications. Here we present one such application, i.e. using quantum coherence to generate and enhance gain in the extreme ultra-violet (XUV)(@58.4nm in Helium) and infra-red (@794.76nm in Rubidium) regimes of electromagnetic radiation. We show that using moderate external coherent drive, a substantial enhancement in the output energy on the lasing transition can be achieved under optimal conditions. We also discuss the role of coherence. The present paper is intended to be pedagogical on this subject of coherence-enhanced lasing.

Jha, Pankaj K.

2013-06-01

381

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

Microsoft Academic Search

In this article we use the pendulum as the vehicle for discussing thetransition from classical to quantum physics. Since student knowledgeof the classical pendulum can be generalized to all harmonic oscillators,we propose that a quantum analysis of the pendulum can leadstudents into the unanticipated consequences of quantum phenomenaat the atomic level. We intend to illustrate how classical deterministicphysical ideas are

Marianne B. Barnes; James Garner; David Reid

2004-01-01

382

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

ERIC Educational Resources Information Center

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

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

2004-01-01

383

Santa Cruz Institute for Particle Physics (SCIPP)  

SciTech Connect

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.

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

1992-11-01

384

Entropic Lower Bound for the Quantum Scattering of Spinless Particles  

NASA Astrophysics Data System (ADS)

In this paper the angle-angular momentum entropic lower bound is proved by using Tsallis-like entropies and Riesz theorem for the quantum scattering of the spinless particles. Numerical estimations of the scattering entropies, as well as an experimental test of the state-independent entropic lower bound, are obtained by using the amplitude reconstruction from the available phase shift analyses for the pion-nucleus scatterings. A standard interpretation of these results in terms of the optimal state dominance is presented. Then, it is shown that experimental pion-nucleus entropies are well described by optimal entropies and that the experimental data are consistent with the principle of minimum distance in the space of scattering states.

Ion, D. B.; Ion, M. L. D.

1998-12-01

385

Physics of quantum relativity through a linear realization  

SciTech Connect

The idea of quantum relativity as a generalized, or rather deformed, version of Einstein (special) relativity has been taking shape in recent years. Following the perspective of deformations, while staying within the framework of Lie algebra, we implement explicitly a simple linear realization of the relativity symmetry, and explore systematically the resulting physical interpretations. Some suggestions we make may sound radical, but are arguably natural within the context of our formulation. Our work may provide a new perspective on the subject matter, complementary to the previous approach(es), and may lead to a better understanding of the physics.

Das, Ashok [Department of Physics, University of Rochester, Rochester, New York 14627 (United States); Kong, Otto C.W. [Department of Physics, National Central University, Chung-li, Taiwan 32054 (China)

2006-06-15

386

Finite-particle-number approach to physics  

SciTech Connect

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

Noyes, H.P.

1982-10-01

387

Hilbert space, the number of Higgs particles and the quantum two-slit experiment  

Microsoft Academic Search

Rigorous mathematical formulation of quantum mechanics requires the introduction of a Hilbert space. By contrast, the Cantorian E-infinity approach to quantum physics was developed largely without any direct reference to the afore mentioned mathematical spaces. In the present work we present a novel reinterpretation of basic ?(?) Cantorian spacetime relations in terms of the Hilbert space of quantum mechanics. In

M. S. El Naschie

2006-01-01

388

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

PubMed

The purpose of this study was to characterize the physical and chemical properties of particles generated from the interaction of tires and road surfaces. Morphology, size distribution, and chemical composition were compared between particles generated using different methods, including on-road collection, laboratory generation under simulated driving conditions, and cryogenic breaking of tread rubber. Both on-road collected and laboratory generated particles exhibited the elongated shape typical of tire wear particles, whereas tread particles were more angular. Despite similar morphology for the on-road collected and the laboratory generated particles, the former were smaller on average. It is not clear at this stage if the difference is significant to the physical and chemical behavior of the particles. The chemical composition of the particles differed, with on-road generated particles containing chemical contributions from sources other than tires, such as pavement or particulates generated from other traffic-related sources. Understanding the differences between these particles is essential in apportioning contaminant contributions to the environment between tires, roadways, and other sources, and evaluating the representativeness of toxicity studies using different types of particulate generated. PMID:19896165

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

2009-11-06

389

Young's double-slit interference for quantum particles  

NASA Astrophysics Data System (ADS)

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

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

2013-04-01

390

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

SciTech Connect

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

Redondo, Antonio [Los Alamos National Laboratory

2010-01-01

391

Space-Based Research in Fundamental Physics and Quantum Technologies  

NASA Astrophysics Data System (ADS)

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

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

392

Research accomplishments and future goals in particle physics  

SciTech Connect

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

Not Available

1990-11-30

393

Studies in theoretical high energy particle physics. Technical progress report, [1991--1992  

SciTech Connect

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.

Aratyn, H.; Brekke, L.; Keung, Wai-Yee; Sukhatme, U.

1993-01-01

394

How to upload a physical quantum state into correlation space  

SciTech Connect

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

Morimae, Tomoyuki [Laboratoire d'Analyse et de Mathematiques Appliquees, Universite Paris-Est Marne-la Vallee, F-77454 Cedex 2 (France)

2011-04-15

395

Physical realization of quantum teleportation for a nonmaximal entangled state  

SciTech Connect

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

Tanaka, Yoshiharu; Asano, Masanari; Ohya, Masanori [Department of Information Sciences, Tokyo University of Science, Noda, Chiba 278-8510 (Japan)

2010-08-15

396

The physical underpinning of security proofs for quantum key distribution  

NASA Astrophysics Data System (ADS)

The dawn of quantum technology unveils a plethora of new possibilities and challenges in the world of information technology, one of which is the quest for secure information transmission. A breakthrough in classical algorithm or the development of a quantum computer could threaten the security of messages encoded using public key cryptosystems based on one-way function such as RSA. Quantum key distribution (QKD) offers an unconditionally secure alternative to such schemes, even in the advent of a quantum computer, as it does not rely on mathematical or technological assumptions, but rather on the universality of the laws of quantum mechanics. Physical concepts associated with quantum mechanics, like the uncertainty principle or entanglement, paved the way to the first successful security proof for QKD. Ever since, further development in security proofs for QKD has been remarkable. But the connection between entanglement distillation and the uncertainty principle has remained hidden under a pile of mathematical burden. Our main goal is to dig the physics out of the new advances in security proofs for QKD. By introducing an alternative definition of private state, which elaborates the ideas of Mayers and Koashi, we explain how the security of all QKD protocols follows from an entropic uncertainty principle. We show explicitly how privacy amplification protocol can be reduced to a private state distillation protocol constructed from our observations about the uncertainty principle. We also derive a generic security proof for one-way permutation-invariant QKD protocols. Considering collective attack, we achieve the same secret key generation rate as the Devetak-Winter's bound. Generalizing an observation from Kraus, Branciard and Renner, we have provided an improved version of the secret key generation rates by considering a different symmetrization. In certain situations, we argue that Azuma's inequality can simplify the security proof considerably, and we explain the implication, on the security level, of reducing a QKD protocol to an entanglement or a more general private state distillation protocol. In a different direction, we introduce a QKD protocol with multiple-photon encoding that can be implemented without a shared reference frame. We prove the unconditional security of this protocol, and discuss some features of the efficiency of multiple-photon QKD schemes in general.

Boileau, Jean Christian

397

State-of-the-Art Particle Physics Detector  

NASA Video Gallery

The Alpha Magnetic Spectrometer is a state-of-the-art particle physics detector being operated by an international team composed of 60 institutes from 16 countries and organized under United States Department of Energy (DOE) sponsorship. It uses the unique environment of space to advance knowledge of the universe and lead to the understanding of the universe's origin.

Mark Garcia

2013-04-01

398

Impact of Elementary Particle Physics on Storage Rings.  

National Technical Information Service (NTIS)

The status of elementary particle physics is described, the contribution of machines to the study is discussed and implications for future storage rings are considered. Some comments are offered as to the limits to growth and the prospects for actually pr...

J. D. Bjorken

1979-01-01

399

Antimatter detection: particle physics model for KDD Cup 2004  

Microsoft Academic Search

What is the difference between matter and anti-matter? A. I. Insight's winning solution on the Particle Physics Task for the 2004 KDD Cup demonstrates how an accurate predictive model can be formulated without knowledge of the content of the data. Information on the data was not available for the modeling, including a description on the outcome to be predicted. In

David S. Vogel; Eric Gottschalk; Morgan C. Wang

2004-01-01

400

Constructing Quarks: A Sociological History of Particle Physics  

Microsoft Academic Search

The title is a challenge. This is an account of the development of the standard model of particle physics, written not by a physicist but by a historian. This is certainly a suitable topic for a historian to analyse, and one might anticipate a refreshingly different account from an outsider sitting above the fray. This is indeed what is provided,

R Barlow

2000-01-01

401

How Particle Physics Cut Nature At Its Joints  

Microsoft Academic Search

This paper presents an epistemological analysis of the search for new conservation laws in particle physics. Discovering conservation laws has posed various challenges concerning the underdetermination of theory by evidence, to which physicists have found various responses. These responses include an appeal to a plenitude principle, a maxim for in- ductive inference, looking for a parsimonious system of generalizations, and

Oliver Schulte

402

Current experiments in elementary particle physics. Revision 1-85  

SciTech Connect

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

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

1985-01-01

403

A 2D quantum walk simulation of two-particle dynamics.  

PubMed

Multidimensional quantum walks can exhibit highly nontrivial topological structure, providing a powerful tool for simulating quantum information and transport systems. We present a flexible implementation of a two-dimensional (2D) optical quantum walk on a lattice, demonstrating a scalable quantum walk on a nontrivial graph structure. We realized a coherent quantum walk over 12 steps and 169 positions by using an optical fiber network. With our broad spectrum of quantum coins, we were able to simulate the creation of entanglement in bipartite systems with conditioned interactions. Introducing dynamic control allowed for the investigation of effects such as strong nonlinearities or two-particle scattering. Our results illustrate the potential of quantum walks as a route for simulating and understanding complex quantum systems. PMID:22403179

Schreiber, Andreas; Gábris, Aurél; Rohde, Peter P; Laiho, Kaisa; Štefa?ák, Martin; Poto?ek, Václav; Hamilton, Craig; Jex, Igor; Silberhorn, Christine

2012-03-08

404

Fractional quantum Hall physics with ultracold Rydberg gases in artificial gauge fields  

NASA Astrophysics Data System (ADS)

We study ultracold Rydberg-dressed Bose gases subject to artificial gauge fields in the fractional quantum Hall (FQH) regime. The characteristics of the Rydberg interaction give rise to interesting many-body ground states different from standard FQH physics in the lowest Landau level. The nonlocal but rapidly decreasing interaction potential favors crystalline ground states for very dilute systems. While a simple Wigner crystal becomes energetically favorable compared to the Laughlin liquid for filling fractions ?<1/12, a correlated crystal of composite particles emerges already for ??1/6 with a large energy gap to the simple Wigner crystal. The presence of a new length scale, the Rydberg blockade radius aB, gives rise to a bubble crystal phase for ??1/4 when the average particle distance becomes less than aB, which describes the region of saturated, almost constant interaction potential. For larger fillings indications for strongly correlated cluster liquids are found.

Grusdt, F.; Fleischhauer, M.

2013-04-01

405

Topics in the standard model of particle physics extension and fourth-order gravity  

NASA Astrophysics Data System (ADS)

In this thesis I present two possible signatures of quantum gravitational phenomenology. The first part of this thesis relates to a Lorentz symmetry violating extension of the standard model of particle physics. Here I show that a Chern-Simons type extension of the quantum electrodynamic (QED) sector of the standard model (SM) leads to the generation of circular polarization for photons. The polarization of scattered photons are analyzed using quantum field theoretic techniques and through the application of a generalized Boltzmann transport equation. In addition to the previously studied optical activity or birefringence effects induced by the particular interaction studied here, the Lorentz invariance violating interaction in question also leads to the generation of circular polarization. The possibility for observation of the effects in the cosmic microwave background (CMB) is discussed, although the circular polarization effects are shown to be at a level which is always sub-dominate to the birefringence effects. The second part of this thesis relates to a fourth-order modification to the general theory of relativity (GR) which has appeared as quantum corrections in the effective spectral action of noncommutative geometry (NCG). A term which is proportional to the square of the Weyl curvature is added to the Einstein-Hilbert action of GR and the the gravitational wave solutions of this modified theory are derived. The implications for the possibility of constraining the parameters of NCG through the analysis of data on the rate of orbit decay of binary pulsars is discussed.

Ochoa, Joseph R.

406

Tomonaga-Luttinger physics in electronic quantum circuits.  

PubMed

In one-dimensional conductors, interactions result in correlated electronic systems. At low energy, a hallmark signature of the so-called Tomonaga-Luttinger liquids is the universal conductance curve predicted in presence of an impurity. A seemingly different topic is the quantum laws of electricity, when distinct quantum conductors are assembled in a circuit. In particular, the conductances are suppressed at low energy, a phenomenon called dynamical Coulomb blockade. Here we investigate the conductance of mesoscopic circuits constituted by a short single-channel quantum conductor in series with a resistance, and demonstrate a proposed link to Tomonaga-Luttinger physics. We reformulate and establish experimentally a recently derived phenomenological expression for the conductance using a wide range of circuits, including carbon nanotube data obtained elsewhere. By confronting both conductance data and phenomenological expression with the universal Tomonaga-Luttinger conductance curve, we demonstrate experimentally the predicted mapping between dynamical Coulomb blockade and the transport across a Tomonaga-Luttinger liquid with an impurity. PMID:23653214

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

2013-01-01

407

Tomonaga-Luttinger physics in electronic quantum circuits  

PubMed Central

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

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

2013-01-01

408

A 'Dysonization' scheme for identifying quasi-particles using non-Hermitian quantum mechanics.  

PubMed

Dyson analysed the low-energy excitations of a ferromagnet using a Hamiltonian that was non-Hermitian with respect to the standard inner product. This allowed for a facile rendering of these excitations (known as spin waves) as weakly interacting bosonic quasi-particles. More than 50 years later, we have the full denouement of the non-Hermitian quantum mechanics formalism at our disposal when considering Dyson's work, both technically and contextually. Here, we recast Dyson's work on ferromagnets explicitly in terms of two inner products, with respect to which the Hamiltonian is always self-adjoint, if not manifestly 'Hermitian'. Then we extend his scheme to doped anti-ferromagnets described by the t-J model, with hopes of shedding light on the physics of high-temperature superconductivity. PMID:23509382

Jones-Smith, Katherine

2013-03-18

409

Holistic Aspects of Quantum Mechanics.  

National Technical Information Service (NTIS)

Aspects of quantum mechanics irreconcilable with classical physics are outlined. Quantum mechanics started with a negative statement about reality, namely: it is impossible to determine momentum and position of a particle simultaneously. Meanwhile it has ...

H. Pietschmann

1987-01-01

410

Two interacting particles in a one-dimensional box: Chaos, Localization and Quantum-Classical Correspondence  

Microsoft Academic Search

We study the model of two interacting particles moving in a 1D-box. The quantum-classical correspondence for the average shape of quantum eigenstates and for the local density of states (LDOS) in energy representation is analyzed. We show that if the classical motion is chaotic, in a deep semiclassical region of a quantum system, both the shape of eigenstates and of

L. Meza-Montes; F. M. Izrailev; J. A. Mendez-Bermudez; S. E. Ulloa

2000-01-01

411

Quantum study of the halfium particle as a reference system in MQDT analysis of H2  

NASA Astrophysics Data System (ADS)

In this paper, we introduce the halfium particle (Ha) as a new molecular reference system for the study of electronic states of molecular hydrogen. For this fictive quantum system, we solve the Schrödinger equation, calculate its Born-Oppenheimer adiabatic potential curves and define a set of Ha quantum defects. The comparison of Ha and standard H2 quantum defects, gives a new insight on the electronic correlation effects in molecular hydrogen.

Bezzaouia, Soumaya; Telmini, Mourad

2007-09-01

412

A guide to experimental particle physics literature, 1991-1996  

SciTech Connect

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

Ezhela, V.V.; Filimonov, B.B.; Lugovsky, S.B. [Inst. for High Energy Physics, Moscow (Russian Federation)] [and others

1996-10-01

413

A Bidirectional Quantum Secure Direct Communication Protocol Based on Five-Particle Cluster State  

NASA Astrophysics Data System (ADS)

To transmit a message safely, five-particle cluster state particles are used to construct a bidirectional quantum secure direct communication protocol. Five-particle cluster state particles are used for both detecting eavesdroppers and transmitting secret messages. All of the five-particle cluster states' photons for detection are mixed to the sending sequence to detect eavesdroppers. The detection rate approaches 88% per qubit. The five-particle cluster states needed are only one fifth of the photons in the sending sequence. In this protocol, there is no photon carrying secret information transmitting in quantum channel, and the classical XOR operation which serves as a one-time-pad is used to ensure the security of the protocol. Compared with three photons of each five-particle cluster state as detection photons, the five photons in this study will decrease the five-particle cluster states needed for detection greatly.

Chang, Yan; Zhang, Shi-Bin; Yan, Li-Li

2013-09-01

414

Quantum space-time and physical reference frames  

NASA Astrophysics Data System (ADS)

Aharonov-Kaufherr model of quantum space-time which accounts Reference Frames quantum effects is considered in Relativistic Quantum Mechanics framework. Due to this effect the quantum corrections to Galilean or Lorentz transformations appears. In particular the Lorentz time boost corrections calculated solving relativistic Heisenberg equations for the quantum clocks model.

Mayburov, S.

1999-03-01

415

Quantum dot-DNA origami binding: a single particle, 3D, real-time tracking study.  

PubMed

The binding process of quantum dots and DNA origami was monitored using a 3D, real-time, single-particle tracking system. Single-molecule binding events were directly observed and precise measurements of the diffusion coefficient and second-order photon correlation function, g(2)(?), were combined to distinguish free quantum dots from different conjugates of nQdot-origami. PMID:23247801

Du, Kan; Ko, Seung Hyeon; Gallatin, Gregg M; Yoon, Heayoung P; Liddle, J Alexander; Berglund, Andrew J

2013-01-30

416

Improved Scheme for Probabilistic Transformation and Teleportation of MultiParticle Quantum States  

Microsoft Academic Search

In most probabilistic teleportation schemes, if the teleportation fails, the unknown quantum state will be completely ruined. In addition, the frequently proposed high-dimensional unitary operations are very difficult to realize experimentally. To maintain the integrity of the unknown quantum state to be teleported, this analysis does not focus attention on the original multi-particle state but seeks to construct a faithful

Min Jiang; Zengke Zhang; Xiangxu Li; Hui Li

2009-01-01

417

The quantum equivalence principle and finite particle creation in expanding universes  

Microsoft Academic Search

A formulation of the equivalence principle in quantum field theory is introduced. The quantum equivalence principle yields implementable Bogolyubov transformations. In this way we find a theory for a scalar field in curved space–time where particle creation is finite for every value of the coupling constant. In the particular case of conformal coupling the initial conditions of positive and negative

Mario Castagnino; Ricardo Weder

1981-01-01

418

For Publisher's use MASSIVE ELEMENTARY PARTICLES AND BLACK HOLES IN RESUMMED QUANTUM GRAVITY  

Microsoft Academic Search

We use exact results in a new approach to quantum gravity to show that the classical conclusion that a massive elementary point particle is a black hole is obviated by quantum loop effects. Further phenomenological implications are discussed. new version of which we discuss presently; composite gravitons; and, asymptotic safety - fixed point theory, recently pursued with success in Refs.

B. F. L. WARD

419

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

Microsoft Academic Search

In this article we use the pendulum as the vehicle for discussing the transition from classical to quantum physics. Since\\u000a student knowledge of the classical pendulum can be generalized to all harmonic oscillators, we propose that a quantum analysis\\u000a of the pendulum can lead students into the unanticipated consequences of quantum phenomena at the atomic level. We intend\\u000a to illustrate

MARIANNE B. BARNES; James Garner; David Reid

420

The XXth International Workshop High Energy Physics and Quantum Field Theory  

NASA Astrophysics Data System (ADS)

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

421

Short-term combined economic emission hydrothermal scheduling using improved quantum-behaved particle swarm optimization  

Microsoft Academic Search

This paper presents an improved quantum-behaved particle swarm optimization (IQPSO) for short-term combined economic emission hydrothermal scheduling, which is formulated as a bi-objective problem: (i) minimizing fuel cost and (ii) minimizing emission cost. In this paper, quantum-behaved particle swarm optimization is improved employing heuristic strategies in order to handle the equality constraints especially water dynamic balance constraints and active power

Chengfu Sun; Songfeng Lu

2010-01-01

422

A Medical Application of Nuclear Physics: Particle Radiotherapy with Protons  

NASA Astrophysics Data System (ADS)

Since the discovery of radiation, applications have been made to medicine. The advent of higher energy particle accelerators in the second half of the twentieth century enabled modern tele-therapy using relatively high energy x-rays and particles. Today mega-voltage (MV) x-rays are the most common modality of delivering high doses of potentially life saving radiation to a wide variety of disease, mostly malignant cancers. However, the maximum radiation dose that can be delivered is always limited by the effects to critical surrounding biologic structures. In many cases, due to their physical properties, ``heavy'' particle radiotherapy with protons and light ions may provide an advantage in this respect over MV x-rays allowing either a higher dose of radiation to be delivered to the volume or, for the same dose, reducing the concomitant damage to critical structures. This motivation, together with recent advances in particle therapy systems that are making the technology more readily available, is serving to grow the field of particle therapy. In particular, treatment with fast protons is becoming more widespread with over 20 facilities operating worldwide and more under construction. This presentation will provide an introduction to heavy particle therapy and additional details specifically on proton therapy.

Farr, Jonathan B.

2006-10-01

423

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

SciTech Connect

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

Not Available

1992-09-01

424

Nuclear and particle physics aspects of hyperon and antinucleon interactions  

SciTech Connect

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

Dover, C.B.

1984-01-01

425

Focus on Particle Physics at the TeV Scale  

Microsoft Academic Search

The present research in particle physics has been progressing very quickly in recent decades thanks to the effort of a large and motivated community of experimentalists and theorists. According to an oversimplified scheme, the experimental effort goes along two main lines which we could broadly identify as the 'high-intensity' (or 'high-luminosity') and the 'high-energy' roads. The former includes high-precision and

Antonio Ereditato; Takaaki Kajita; Antonio Masiero

2007-01-01

426

Nonlinear Aspects of Quantum Plasma Physics: Nanoplasmonics and Nanostructures in Dense Plasmas  

Microsoft Academic Search

We present a short review of recent developments in nonlinear quantum plasma physics, including quantum hydrodynamic and effective nonlinear shrödinger equation formalisms, for describing collective phenomena in quantum plasmas. As examples we discuss simulation studies of the formation and dynamics of dark solitons and vortices, and of nonlinear interactions between intense circularly polarized electromagnetic (CPEM) waves and electron plasma oscillations

Bengt Eliasson; Padma K. Shukla

2009-01-01

427

Silicon Detectors-Tools for Discovery in Particle Physics  

SciTech Connect

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

Krammer, Manfred [Institute of High Energy Physics, Austrian Academy of Sciences, Vienna (Austria)

2009-07-07

428

The neutron and its role in cosmology and particle physics  

SciTech Connect

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.

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

429

EDITORIAL: Focus on Dark Matter and Particle Physics  

NASA Astrophysics Data System (ADS)

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

Aprile, Elena; Profumo, Stefano

2009-10-01

430

Superluminal Particles, Cosmology and Cosmic-Ray Physics  

NASA Astrophysics Data System (ADS)

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 .

Gonzalez-Mestres, Luis

2003-07-01

431

Life at the interface of particle physics and string theory  

NASA Astrophysics Data System (ADS)

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

Schellekens, A. N.

2013-10-01

432

How to upload a physical quantum state into correlation space  

NASA Astrophysics Data System (ADS)

In the framework of the computational tensor network [Phys. Rev. Lett.PRLTAO0031-900710.1103/PhysRevLett.98.220503 98, 220503 (2007)], the quantum computation is performed in a virtual linear space called the correlation space. It was recently shown [Phys. Rev. Lett.PRLTAO0031-900710.1103/PhysRevLett.103.050503 103, 050503 (2009)] that a state in a correlation space can be downloaded to the real physical space. In this paper, conversely, we study how to upload a state from a real physical space to the correlation space. After showing the impossibility of cloning a state between a real physical space and the correlation space, we propose a simple teleportation-like method of uploading. This method also enables the Gottesman-Chuang gate teleportation trick and entanglement swapping in the virtual-real hybrid setting. Furthermore, compared with the inverse of the downloading method by Cai [Phys. Rev. Lett.PRLTAO0031-900710.1103/PhysRevLett.103.050503 103, 050503 (2009)], which also works to upload, the proposed uploading method has several advantages.

Morimae, Tomoyuki

2011-04-01

433

A Novel Particle Detector: Quantum Dot Doped Liquid Scintillator  

NASA Astrophysics Data System (ADS)

Quantum dots are semiconducting nanocrystals. When excited by light shorter then their characteristic wavelength, they re-emit in a narrow band around this wavelength. The size of the quantum is proportional to the characteristic wavelength so they can be tuned for many applications. CdS quantum dots are made in wavelengths from 360nm to 460nm, a perfect range for the sensitivity of photo-multiplier tubes. The synthesis of quantum dots automatically leaves them in toluene, a good organic scintillator and Cd is a particularly interesting material as it has one of the highest thermal neutron cross sections and has several neutrinoless double beta decay and double electron capture isotopes. The performance of quantum dot loaded scintillator compared to standard scintillators is measured and some unique properties presented. )

Winslow, Lindley; Conrad, Janet; Jerry, Ruel

2010-02-01

434

The theoretical apparatus of semantic realism: A new language for classical and quantum physics  

Microsoft Academic Search

The standard interpretation of quantum physics (QP) and some recent generalizations of this theory rest on the adoption of a rerificationist theory of truth and meaning, while most proposals for modifying and interpreting QP in a realistic way attribute an ontological status to theoretical physical entities (ontological realism). Both terms of this dichotomy are criticizable, and many quantum paradoxes can

Claudio Garola; Luigi Solombrino

1996-01-01

435

Reflections: What Does Quantum Physics of Storytelling Mean for Change Management?  

Microsoft Academic Search

The paradigm shift to quantum physics will mean new approaches to change management and storytelling. Because what we thought we knew about space, time and matter has changed, our storytelling of the history, present and future will be different. My purpose is to reflect on the way changes in what I call the ‘quantum physics of storytelling’ prompt important changes

David M. Boje

2012-01-01

436

Physical interactions of charged particles for radiotherapy and space applications.  

PubMed

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

Zeitlin, Cary

2012-11-01

437

Particle physics and cosmology, Task C. Progress report, January 1992--April 1993.  

National Technical Information Service (NTIS)

The research has spanned many topics at the boundary of particle physics and cosmology. The major focus has been in the general areas of inflationary cosmology, cosmological phase transitions, astrophysical constraints to particle physics theories, and da...

M. S. Turner

1993-01-01

438

Elementary particle physics at the University of Florida. Annual report  

SciTech Connect

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.

Field, R.D.; Ramond, P.M.; Sikivie, P. [and others

1995-12-01

439

'Who Thinks Abstractly?': Quantum Theory and the Architecture of Physical Concepts  

SciTech Connect

Beginning with its introduction by W. Heisenberg, quantum mechanics was often seen as an overly abstract theory, mathematically and physically, vis-a-vis classical physics or relativity. This perception was amplified by the fact that, while the quantum-mechanical formalism provided effective predictive algorithms for the probabilistic predictions concerning quantum experiments, it appeared unable to describe, even by way idealization, quantum processes themselves in space and time, in the way classical mechanics or relativity did. The aim of the present paper is to reconsider the nature of mathematical and physical abstraction in modern physics by offering an analysis of the concept of ''physical fact'' and of the concept of 'physical concept', in part by following G. W. F. Hegel's and G. Deleuze's arguments concerning the nature of conceptual thinking. In classical physics, relativity, and quantum physics alike, I argue, physical concepts are defined by the following main features - 1) their multi-component multiplicity; 2) their essential relations to problems; 3) and the interactions between physical, mathematical, and philosophical components within each concept. It is the particular character of these interactions in quantum mechanics, as defined by its essentially predictive (rather than descriptive) nature, that distinguishes it from classical physics and relativity.

Plotnitsky, Arkady [Theory and Cultural Studies Program, Purdue University, West Lafayette, IN 47907 (United States)

2011-03-28

440

Ground State of a System of N Hard Core Quantum Particles in 1D Box  

Microsoft Academic Search

The ground state of a system of $N$ impenetrable hard core quantum particles\\u000ain a 1-D box is analyzed by using a new scheme applied recently to study a\\u000asimilar system of two such particles {\\\\it [Centl. Eur. J. Phys., 2(4), 709\\u000a(2004)]}. Accordingly, each particle of the system behaves like an independent\\u000aentity represented by a {\\\\it macro-orbital}, -a

Yatendra S. Jain

2006-01-01

441

Ground State of a System of N Hard Core Quantum Particles in 1D Box  

Microsoft Academic Search

The ground state of a system of $N$ impenetrable hard core quantum particles in a 1-D box is analyzed by using a new scheme applied recently to study a similar system of two such particles {\\\\it [Centl. Eur. J. Phys., 2(4), 709 (2004)]}. Accordingly, each particle of the system behaves like an independent entity represented by a {\\\\it macro-orbital}, -a

Yatendra S Jain

2006-01-01

442

Proceedings of the sixth international conference on electronics for particle physics  

Microsoft Academic Search

The Sixth Conference on Electronics for Particle Physics continued the LeCroy tradition of providing a unique forum for the leaders in the field to meet, report and compare notes on what has become one of the most important (and expensive) components of a particle physics physics experiments today. As our field continues to depend on special electronics developed for particle

G. J. Blanar; R. L. Sumner

1997-01-01

443

PARTICLE PHYSICS: The Final Tally Leaves LEP a Probable Loser.  

PubMed

Physicists at CERN, the European particle physics laboratory near Geneva, are making a last-ditch appeal to postpone demolition of the lab's Large Electron-Positron (LEP) collider. Scheduled to be scrapped in September to make room for a new device, the Large Hadron Collider, LEP was granted a 1-month stay of execution so physicists could continue experiments hinting at evidence for the Higgs boson--a theoretical particle that physicists have coveted for decades. On 8 November, CERN's director-general turned down a further extension, but the executive committee of the lab's staff association blasted the decision, saying that the case against LEP had not been made clearly enough. PMID:17787224

Morton, O

2000-11-17

444

Theoretical Physics Student Seminar 2008-2009 Alternative Theories of Gravity: Loop Quantum Gravity and Loop Quantum Cosmology  

Microsoft Academic Search

Quantizing gravity and unifying it with the other fundamental inter- actions has been the focus of theoretical physics research in the last cou- ple of decades. Among dierent attempts, numerous theories have been suggested, some representing a more conservative approach, while others introduce new underlying fundamental theories, which reduce to known physics in certain limits. Loop Quantum Gravity (LQG) represents

Marcin Dukalski

2009-01-01

445

Pseudo-Hermitian quantum dynamics of tachyonic spin-1/2 particles  

NASA Astrophysics Data System (ADS)

We investigate the spinor solutions, the spectrum and the symmetry properties of a matrix-valued wave equation whose plane-wave solutions satisfy the superluminal (tachyonic) dispersion relation E^2 = \\vec{p}^{\\,2} - m^2, where E is the energy, \\vec{p} is the spatial momentum and m is the mass of the particle. The equation reads (i????? - ?5?m)? = 0, where ?5 is the fifth current. The tachyonic equation is shown to be {CP} invariant and T invariant. The tachyonic Hamiltonian H_5 = \\vec{\\alpha }\\cdot \\vec{p} + \\beta \\, \\gamma ^5 \\, m breaks parity and is non-Hermitian but fulfils the pseudo-Hermitian property H_5(\\vec{r}) = P \\, H^{+}_5(-\\vec{r}) \\, P^{-1} = {P}\\, H^{+}_5(\\vec{r}) \\, {P}^{-1}, where P is the parity matrix and {P} is the full parity transformation. The energy eigenvalues and eigenvectors describe a continuous spectrum of plane-wave solutions (which correspond to real eigenvalues for |\\vec{p}| \\ge m) and evanescent waves, which constitute resonances and anti-resonances with complex-conjugate pairs of resonance eigenvalues (for |\\vec{p}| < m). In view of additional algebraic properties of the Hamiltonian which supplement the pseudo-Hermiticity, the existence of a resonance energy eigenvalue E implies that E*, -E and -E* also constitute resonance energies of H5. This article is part of a special issue of Journal of Physics A: Mathematical and Theoretical devoted to ‘Quantum physics with non-Hermitian operators’.

Jentschura, U. D.; Wundt, B. J.

2012-11-01

446

Model of cosmology and particle physics at an intermediate scale  

SciTech Connect

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

Bastero-Gil, M. [Centre of Theoretical Physics, University of Sussex, Falmer, Brighton, BN1 9QJ (United Kingdom); Di Clemente, V. [Department of Theoretical Physics, University of Oxford, 1, Keble Road, Oxford OX1 3NP (United Kingdom); King, S. F. [Department of Physics and Astronomy, University of Southampton, Highfield, Southampton, SO17 1BJ (United Kingdom)

2005-05-15

447

Multi-party quantum secret sharing with the single-particle quantum state to encode the information  

NASA Astrophysics Data System (ADS)

We present a three-party quantum secret sharing (QSS) scheme via the entangled Greenberger-Horne-Zeilinger state. In this scheme, the sender Alice encodes her arbitrary secret information by means of preparing a single-particle quantum state. The agent Bob obtains his shared information according to his hobby, while Charlie can easily calculate his shared information. The proposed scheme is secure. It is shown that even a dishonest agent, who may avoid the security checking, cannot obtain any useful information. Moreover, we further investigate the multi-party QSS scheme which allows most agents to predetermine their information.

Chen, Xiu-Bo; Niu, Xin-Xin; Zhou, Xin-Jie; Yang, Yi-Xian

2013-01-01

448

Several teleportation schemes of an arbitrary unknown multi-particle state via different quantum channels  

NASA Astrophysics Data System (ADS)

We first provide four new schemes for two-party quantum teleportation of an arbitrary unknown multi-particle state by using three-, four-, and five-particle states as the quantum channel, respectively. The successful probability and fidelity of the four schemes reach 1. In the first two schemes, the receiver can only apply one of the unitary transformations to reconstruct the original state, making it easier for these two schemes to be directly realized. In the third and fourth schemes, the sender can preform Bell-state measurements instead of multipartite entanglement measurements of the existing similar schemes, which makes real experiments more suitable. It is found that the last three schemes may become tripartite controlled teleportation schemes of teleporting an arbitrary multi-particle state after a simple modification. Finally, we present a new scheme for three-party sharing an arbitrary unknown multi-particle state. In this scheme, the sender first shares three three-particle GHZ states with two agents. After setting up the secure quantum channel, an arbitrary unknown multi-particle state can be perfectly teleported if the sender performs three Bell-state measurements, and either of two receivers operates an appropriate unitary transformation to obtain the original state with the help of other receiver's three single-particle measurements. The successful probability and fidelity of this scheme also reach 1. It is demonstrated that this scheme can be generalized easily to the case of sharing an arbitrary unknown multi-particle state among several agents.

Peng, Jia-Yin; Mo, Zhi-Wen

2013-05-01

449

[Investigations in dynamics of gauge theories in theoretical particle physics  

SciTech Connect

The major theme of the theoretical physics research conducted under DOE support over the past several years has been within the rubric of the standard model, and concerned the interplay between symmetries and dynamics. The research was thus carried out mostly in the context of gauge field theories, and usually in the presence of chiral fermions. Dynamical symmetry breaking was examined both from the point of view of perturbation theory, as well as from non-perturbative techniques associated with certain characteristic features of specific theories. Among the topics of research were: the implications of abelian and non-abelian anomalies on the spectrum and possible dynamical symmetry breaking in any theory, topological and conformal properties of quantum fields in two and higher dimensions, the breaking of global chiral symmetries by vector-like gauge theories such as QCD, the phenomenological implications of a strongly interacting Higgs sector in the standard model, and the application of soliton ideas to the physics to be explored at the SSC.

Not Available

1993-02-01

450

Charged vs. Neutral particle creation in expanding Universes: A Quantum Field Theoretic Treatment  

Microsoft Academic Search

A complete quantum field theoretic study of charged and neutral particle creation in a rapidly\\/adiabatically expanding Friedman-Robertson-Walker metric for an O(4) scalar field theory with quartic interactions (admitting a phase transition) is given. Quantization is carried out by inclusion of quantum fluctuations. We show that the quantized Hamiltonian admits an su(1,1) invariance. The squeezing transformation diagonalizes the Hamiltonian and shows

B. Bambah; C. Mukku

2003-01-01

451

Angle-angular-momentum entropic bounds and optimal entropies for quantum scattering of spinless particles  

Microsoft Academic Search

In this paper the angle-angular-momentum entropic lower and upper bounds are proved by using Tsallis-like entropies, the Riesz theorem, and the Lagrange multiplier method for the quantum scattering of the spinless particles. A connection between optimal states and the most stringent entropic bounds on Tsallis-like entropies in the quantum scattering is established. The results of experimental tests of the state-independent

D. B. Ion; M. L. D. Ion

1999-01-01

452

Quantum cellular automata: the physics of computing with arrays of quantum dot molecules  

Microsoft Academic Search

We discuss the fundamental limits of computing using a new paradigm for quantum computation, cellular automata composed of arrays of coulombically coupled quantum dot molecules, which we term quantum cellular automata (QCA). Any logical or arithmetic operation can be performed in this scheme. QCA's provide a valuable concrete example of quantum computation in which a number of fundamental issues come

C. S. Lent; P. D. Tougaw; W. Porod

1994-01-01

453

Particle Physics Catalysis of Thermal Big Bang Nucleosynthesis  

SciTech Connect

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.

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

454

Modelling Systems of Classical/Quantum Identical Particles by Focusing on Algorithms  

ERIC Educational Resources Information Center

|A procedure modelling ideal classical and quantum gases is discussed. The proposed approach is mainly based on the idea that modelling and algorithm analysis can provide a deeper understanding of particularly complex physical systems. Appropriate representations and physical models able to mimic possible pseudo-mechanisms of functioning and…

Guastella, Ivan; Fazio, Claudio; Sperandeo-Mineo, Rosa Maria

2012-01-01

455

Women Researchers in the Theoretical Physics, Particle Physics, and Modeling Laboratory at Oujda University, Morocco (abstract)  

NASA Astrophysics Data System (ADS)

Moroccan women are underrepresented among researchers at Oujda University. They account for about 10% of the scientific research done there. The principal reasons are the difficulties in research areas at the university and family and social obligations. The university's Theoretical Physics, Particle Physics and Modeling Laboratory (LPTPM) includes 10 professors, nine PhDs, and nine graduate students. Three of them are women: one professor, one PhD, and one student. All work in the ATLAS collaboration of more than 150 laboratories around the world. ATLAS is one of four detectors to be operated on the Large Hadron Collider at CERN in Switzerland.

Dekhissi, B.; Dekhissi, H.; Derkaoui, J.; Elkharrim, A.; Maaroufi, Fatiha

2009-04-01

456

A sampling algorithm to estimate the effect of fluctuations in particle physics data  

NASA Astrophysics Data System (ADS)

Background properties in experimental particle physics are typically estimated using large data sets. However, different events can exhibit different features both because of the quantum mechanical nature of the underlying physics and due to statistical fluctuations. While signal and background fractions in a given data set can be evaluated using a maximum likelihood estimator, the shapes of the corresponding distributions are traditionally obtained using high-statistics control samples, which normally neglects the effect of fluctuations. On the other hand, if it was possible to subtract background using templates that take fluctuations into account, this would be expected to improve the resolution of observables of interest, and to reduce systematics depending on the analysis. This study is an initial step in this direction. We propose a novel algorithm inspired by the Gibbs sampler that estimates the shapes of signal and background probability density functions from a given collection of particles, using control sample templates as initial conditions and refining them to include the effect of fluctuations. Results on Monte Carlo data are presented, and the prospects for future development are discussed.

Colecchia, Federico

2013-02-01

457

Position sensitive photon detectors for nuclear physics, particle physics and healthcare applications  

NASA Astrophysics Data System (ADS)

Modern experiments in hadronic physics require detector systems capable of identifying and reconstructing all final-state particles and their momentum vectors. Imaging Cherenkov counters (RICH and DIRC) are frequently employed in nuclear and particle physics experiments. These detectors require high-rate, single-photon capable light detection system with sufficient granularity and position resolution. Several candidate systems are available, ranging from multi-anode photomultiplier tubes to micro-channel plate systems to silicon photomultipliers. Each of these detection solutions has particular advantages and disadvantages. Detailed studies of rate dependence, cross-talk, time-resolution and position resolution for a range of available photon detection solutions are presented. These properties make these photon detection systems ideal for radionuclide imaging applications. Cherenkov radiation can also be used for medical imaging applications. Two different applications using the Cherenkov effect for radionuclide imaging will be reviewed.

Seitz, B.

2012-01-01

458

Wave-Particle Duality and Uncertainty Principle: Phenomenographic Categories of Description of Tertiary Physics Students' Depictions  

ERIC Educational Resources Information Center

Quantum mechanics is often thought to be a difficult subject to understand, not only in the complexity of its mathematics but also in its conceptual foundation. In this paper we emphasize students' depictions of the uncertainty principle and wave-particle duality of quantum events, phenomena that could serve as a foundation in building an…

Ayene, Mengesha; Kriek, Jeanne; Damtie, Baylie

2011-01-01

459

Wave-Particle Duality and Uncertainty Principle: Phenomenographic Categories of Description of Tertiary Physics Students' Depictions  

ERIC Educational Resources Information Center

|Quantum mechanics is often thought to be a difficult subject to understand, not only in the complexity of its mathematics but also in its conceptual foundation. In this paper we emphasize students' depictions of the uncertainty principle and wave-particle duality of quantum events, phenomena that could serve as a foundation in building an…

Ayene, Mengesha; Kriek, Jeanne; Damtie, Baylie

2011-01-01

460

Quantum State Determination: Quorum for a Particle in One Dimension.  

ERIC Educational Resources Information Center

|Explains that the quantal state describes a statistical ensemble of similar systems identically prepared, and is not to be identified with any single system. Shows how to determine empirically the general quantum state by calculations involving only the measured mean values of a set of observables called a "Quorum." (Author/GA)|

Band, William; Park, James L.

1979-01-01

461

Relativistic Quantum Mechanics of Three-Particle Systems  

NASA Astrophysics Data System (ADS)

A brief review of the Bakamjian-Thomas method for constructing Poincaré invariant models of few-particle systems is presented. An application of the method to a simple model of the coupled N - ?N - ??N system is outlined. This three-particle model contains vertex interactions as well as renormalization contributions.

Fuda, Michael G.

462

Particle abundances in our Universe: Deterministic, or randomly determined via quantum cosmology or inflationary quantum fluctuations\\\\?  

Microsoft Academic Search

There is a rather large class of particle species that may never achieve a thermal abundance after inflation. The abundance, relative to photons, of these particles (if stable), or the stable decay products from these particles, or the abundances of thermal relics diluted by an entropy-producing decay of such a particle, may not be possible to uniquely predict, even with

Hardy M. Hodges

1992-01-01

463

Special issue on quantum physics with non-Hermitian operators Special issue on quantum physics with non-Hermitian operators  

NASA Astrophysics Data System (ADS)

This is a call for contributions to a special issue of Journal of Physics A: Mathematical and Theoretical dedicated to quantum physics with non-Hermitian operators. The main motivation behind this special issue is to gather together recent results, developments and open problems in this rapidly evolving field of research in a single comprehensive volume. We expect that such a special issue will become a valuable reference for the broad scientific community working in mathematical and theoretical physics. The issue will be open to all contributions containing new results on non-Hermitian theories which are explicitly PT-symmetric and/or pseudo-Hermitian or quasi-Hermitian. The main novelties in the past years in this area have been many experimental observations, realizations, and applications of PT symmetric Hamiltonians in optics and microwave cavities. We especially invite contributions on the theoretical interpretations of these recent PT-symmetric experiments and on theoretical proposals for new experiments. Editorial policy The Guest Editors for this issue are Carl Bender, Andreas Fring, Uwe Guenther and Hugh Jones. The areas and topics for this issue include, but are not limited to: spectral problems novel properties of complex optical potentials PT-symmetry related threshold lasers and spectral singularities construction of metric operators scattering theory supersymmetric theories Lie algebraic and Krein-space methods random matrix models classical and semi-classical models exceptional points in model systems operator theoretic approaches microwave cavities aspects of integrability and exact solvability field theories with indefinite metric All contributions will be refereed and processed according to the usual procedure of the journal. Papers should report original and significant research that has not already been published. Guidelines for preparation of contributions The deadline for contributed papers will be 31 March 2012. This deadline will allow the special issue to appear before the end of November 2012. There is a nominal page limit of 15 printed pages per contribution (invited review papers can be longer). For papers exceeding this limit, the Guest Editors reserve the right to request a reduction in length. Further advice on publishing your work in Journal of Physics A: Mathematical and Theoretical may be found at iopscience.iop.org/jphysa. Contributions to the special issue should be submitted by web upload via authors.iop.org, or by email to jphysa@iop.org, quoting 'JPhysA Special issue on quantum physics with non-Hermitian operators'. Submissions should ideally be in standard LaTeX form. Please see the website for further information on electronic submissions. All contributions should be accompanied by a read-me file or covering letter giving the postal and e-mail addresses for correspondence. The Publishing Office should be notified of any subsequent change of address. The special issue will be published in the print and online versions of the journal.

Bender, Carl M.; Fring, Andreas; Guenther, Uwe; Jones, Hugh F.

2012-01-01

464

Special issue on quantum physics with non-Hermitian operators Special issue on quantum physics with non-Hermitian operators  

NASA Astrophysics Data System (ADS)

This is a call for contributions to a special issue of Journal of Physics A: Mathematical and Theoretical dedicated to quantum physics with non-Hermitian operators. The main motivation behind this special issue is to gather together recent results, developments and open problems in this rapidly evolving field of research in a single comprehensive volume. We expect that such a special issue will become a valuable reference for the broad scientific community working in mathematical and theoretical physics. The issue will be open to all contributions containing new results on non-Hermitian theories which are explicitly PT-symmetric and/or pseudo-Hermitian or quasi-Hermitian. The main novelties in the past years in this area have been many experimental observations, realizations, and applications of PT symmetric Hamiltonians in optics and microwave cavities. We especially invite contributions on the theoretical interpretations of these recent PT-symmetric experiments and on theoretical proposals for new experiments. Editorial policy The Guest Editors for this issue are Carl Bender, Andreas Fring, Uwe Guenther and Hugh Jones. The areas and topics for this issue include, but are not limited to: spectral problems novel properties of complex optical potentials PT-symmetry related threshold lasers and spectral singularities construction of metric operators scattering theory supersymmetric theories Lie algebraic and Krein-space methods random matrix models classical and semi-classical models exceptional points in model systems operator theoretic approaches microwave cavities aspects of integrability and exact solvability field theories with indefinite metric All contributions will be refereed and processed according to the usual procedure of the journal. Papers should report original and significant research that has not already been published. Guidelines for preparation of contributions The deadline for contributed papers will be 31 March 2012. This deadline will allow the special issue to appear before the end of November 2012. There is a nominal page limit of 15 printed pages per contribution (invited review papers can be longer). For papers exceeding this limit, the Guest Editors reserve the right to request a reduction in length. Further advice on publishing your work in Journal of Physics A: Mathematical and Theoretical may be found at iopscience.iop.org/jphysa. Contributions to the special issue should be submitted by web upload via authors.iop.org/, or by email to jphysa@iop.org, quoting 'JPhysA Special issue on quantum physics with non-Hermitian operators'. Submissions should ideally be in standard LaTeX form. Please see the website for further information on electronic submissions. All contributions should be accompanied by a read-me file or covering letter giving the postal and e-mail addresses for correspondence. The Publishing Office should be notified of any subsequent change of address. The special issue will be published in the print and online versions of the journal.

Bender, Carl M.; Fring, Andreas; Guenther, Uwe; Jones, Hugh F.

2012-01-01

465

Probing the "dark" fraction of core-shell quantum dots by ensemble and single particle pH-dependent spectroscopy.  

PubMed

The optical properties of core-shell CdSe-ZnS quantum dots (QDs) are characterized by complex photophysics leading to difficulties in interpreting quantitative measurements based on QD emission. By comparing the pH dependence of fluorescence of single QDs to that of an ensemble, we have been able to propose a molecular scale model of how QD surface chemical and physical processes are affected by protons and oxygen. We show that the connection between the ensemble fluorescence intensity and the single QD fluorescence properties such as dark fraction, blinking, particle brightness, and a multiexponential fluorescence lifetime decay is not trivial. The ensemble fluorescence intensity is more weakly dependent on pH than the single particle fluorescence which, together with fluorescence lifetime analysis, provided evidence that the dark fraction of QDs emits photons with low quantum efficiency and long lifetime. We uncovered two surface-dependent mechanisms that affected the fluorescence emission: an immediate physical effect of charges surrounding the QD and an irreversible chemical effect from reaction of the H(+) and O(2) with the QD shell surface. These results will have important implications for those using QD-based fluorescence lifetime imaging as well as for proper implementation of these probes for quantitative cellular imaging applications. PMID:22023370

Durisic, Nela; Godin, Antoine G; Walters, Derrel; Grütter, Peter; Wiseman, Paul W; Heyes, Colin D

2011-10-28

466

Probing the "Dark" Fraction of Core-Shell Quantum Dots by Ensemble and Single Particle pH-Dependent Spectroscopy  

PubMed Central

The optical properties of core-shell CdSe-ZnS quantum dots (QDs) are characterized by complex photophysics leading to difficulties in interpreting quantitative measurements based on QD emission. By comparing the pH dependence of fluorescence of single QDs to that of an ensemble, we have been able to propose a molecular scale model of how QD surface chemical and physical processes are affected by protons and oxygen. We show that the connection between the ensemble fluorescence intensity and the single QD fluorescence properties such as dark fraction, blinking, particle brightness and a multi-exponential fluorescence lifetime decay is not trivial. The ensemble fluorescence intensity is more weakly dependent on pH than the single particle fluorescence which, together with fluorescence lifetime analysis, provided evidence that the dark fraction of QDs emits photons with low quantum efficiency and long lifetime. We uncovered two surface-dependent mechanisms that affected the fluorescence emission: an immediate physical effect of charges surrounding the QD and an irreversible chemical effect from reaction of the H+ and O2 with the QD shell surface. These results will have important implications for those using QD-based fluorescence lifetime imaging as well as for proper implementation of these probes for

M. Asorey (Universidad de Zaragoza, Spain)