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Heisenberg's Uncertainty Relation and Bell Inequalities in High Energy Physics

Di Domenico, A.; Gabriel, A.; Hiesmayr, B. C.; Hipp, F.; Huber, M.; Krizek, G.; Mühlbacher, K.; Radic, S.; Spengler, Ch.; Theussl, L.
Tipo: Artigo de Revista Científica
Publicado em 24/01/2011 Português
Relevância na Pesquisa
96.9298%
An effective formalism is developed to handle decaying two-state systems. Herewith, observables of such systems can be described by a single operator in the Heisenberg picture. This allows for using the usual framework in quantum information theory and, hence, to enlighten the quantum feature of such systems compared to non-decaying systems. We apply it to systems in high energy physics, i.e. to oscillating meson-antimeson systems. In particular, we discuss the entropic Heisenberg uncertainty relation for observables measured at different times at accelerator facilities including the effect of CP violation, i.e. the imbalance of matter and antimatter. An operator-form of Bell inequalities for systems in high energy physics is presented, i.e. a Bell-witness operator, which allows for simple analysis of unstable systems.; Comment: 17 pages

High-energy physics and cosmological perturbations: observing new physics at large scales

Chialva, Diego
Tipo: Artigo de Revista Científica
Publicado em 10/12/2013 Português
Relevância na Pesquisa
96.95337%
Correlators of primordial perturbations could provide us with the signatures of physics at earlier times/higher momentum scales than inflation. The key-mechanisms are the interference and cumulation in time related to the interplay of negative- and positive-frequency components of fields and energy density generated by the high-momentum scale physics. Here, we discuss which signatures are universal for such scenarios, and which ones instead would distinguish the specific cases (for example modified initial states for inflationary perturbations or modified dispersion relations). We also discuss the scale dependence of the correlators in presence of these signatures, especially for some scenarios, and how this could be interesting for observations.; Comment: 7 pages. Prepared for the proceedings of the European Physical Society Conference on High Energy Physics EPS-HEP2013, 18-24 July 2013, Stockholm, Sweden

Correlation between radiation processes in silicon and long-time degradation of detectors for high energy physics experiments

Lazanu, Sorina; Lazanu, Ionel
Tipo: Artigo de Revista Científica
Publicado em 20/11/2006 Português
Relevância na Pesquisa
96.8915%
In this contribution, the correlation between fundamental interaction processes induced by radiation in silicon and observable effects which limit the use of silicon detectors in high energy physics experiments is investigated in the frame of a phenomenological model which includes: generation of primary defects at irradiation starting from elementary interactions in silicon; kinetics of defects, effects at the p-n junction detector level. The effects due to irradiating particles (pions, protons, neutrons), to their flux, to the anisotropy of the threshold energy in silicon, to the impurity concentrations and resistivity of the starting material are investigated as time, fluence and temperature dependences of detector characteristics. The expected degradation of the electrical parameters of detectors in the complex hadron background fields at LHC & SLHC are predicted.; Comment: prepared for the 10th International Symposium on Radiation Physics, 17-22 September, 2006, Coimbra, Portugal

Proceedings of the 2009 CERN-Latin-American School of High-Energy Physics, Recinto Quirama, Colombia, 15 - 28 March 2009

Grojean, C.; Spiropulu, M.
Tipo: Artigo de Revista Científica
Publicado em 28/10/2010 Português
Relevância na Pesquisa
97.00554%
The CERN-Latin-American School of High-Energy Physics is intended to give young physicists an introduction to the theoretical aspects of recent advances in elementary particle physics. These proceedings contain lectures on quantum field theory, quantum chromodynamics, physics beyond the Standard Model, neutrino physics, flavour physics and CP violation, particle cosmology, high-energy astro-particle physics, and heavy-ion physics, as well as trigger and data acquisition, and commissioning and early physics analysis of the ATLAS and CMS experiments. Also included are write-ups of short review projects performed by the student discussions groups.; Comment: 10 lectures, 560 pages, published as CERN Yellow Report http://cdsweb.cern.ch/record/1119305

Silicon detectors for the next generation of high energy physics experiments: expected degradation

Lazanu, I.; Lazanu, S.
Tipo: Artigo de Revista Científica
Publicado em 31/12/2005 Português
Relevância na Pesquisa
96.95576%
There exists an enormous interest for the study of very high energy domain in particle physics, both theoretically and experimentally, in the aim to construct a general theory of the fundamental constituents of matter and of their interactions. Until now, semiconductor detectors have widely been used in modern high energy physics experiments. They are elements of the high resolution vertex and tracking system, as well as of calorimeters. The main motivation of this work is to discuss how to prepare some possible detectors - only silicon option being considered, for the new era of HEP challenges because the bulk displacement damage in the detector, consequence of irradiation, produces effects at the device level that limit their long time utilisation, increasing the leakage current and the depletion voltage, eventually up to breakdown, and thus affecting the lifetime of detector systems. In this paper, physical phenomena that conduce to the degradation of the detector are discussed and effects are analysed at the device level (leakage current and effective carrier concentration) in the radiation environments expected in the next generation of hadron colliders after LHC, at the next lepton and gamma-gamma colliders, as well as in astroparticle experiments...

Indian Contributions to High Energy Physics in the 20th Century

Rajasekaran, G.
Tipo: Artigo de Revista Científica
Publicado em 07/02/2006 Português
Relevância na Pesquisa
97.03036%
The inward bound path of discovery unravelling the mysteries of matter and the forces that hold it together has culminated at the end of the twentieth century in a theory of the Fundamental Forces of Nature based on Nonabelian Gauge Fields, called the Standard Model of High Energy Physics. In this article we trace the historical development of the ideas and the experimental discoveries on which this theory is based. We also mark significant Indian contributions wherever possible. Finally we have a glimpse at future developments. An Appendix on more Indian contributions is added at the end.; Comment: 15 pages. Invited talk presented at the XIV DAE Symposium on High Energy Physics, Univ. of Hyderabad, Dec. 2000

Citation Networks in High Energy Physics

Lehmann, S.; Lautrup, B.; Jackson, A. D.
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
96.95337%
The citation network constituted by the SPIRES data base is investigated empirically. The probability that a given paper in the SPIRES data base has $k$ citations is well described by simple power laws, $P(k) \propto k^{-\alpha}$, with $\alpha \approx 1.2$ for $k$ less than 50 citations and $\alpha \approx 2.3$ for 50 or more citations. Two models are presented that both represent the data well, one which generates power laws and one which generates a stretched exponential. It is not possible to discriminate between these models on the present empirical basis. A consideration of citation distribution by subfield shows that the citation patterns of high energy physics form a remarkably homogeneous network. Further, we utilize the knowledge of the citation distributions to demonstrate the extreme improbability that the citation records of selected individuals and institutions have been obtained by a random draw on the resulting distribution.; Comment: 9 pages, 6 figures, 2 tables

Proceedings of the 2012 European School of High-Energy Physics (ESHEP 2012), La Pommeraye, Anjou, France, 06-19 Jun 2012

Grojean, C.; Mulders, M.
Tipo: Artigo de Revista Científica
Publicado em 28/04/2015 Português
Relevância na Pesquisa
96.88383%
The European School of High-Energy Physics is intended to give young physicists an introduction to the theoretical aspects of recent advances in elementary particle physics. These proceedings contain lecture notes on the Standard Model of electroweak interactions, quantum chromodynamics, flavour physics, physics beyond the Standard Model, neutrino physics, and cosmology.; Comment: 8 lectures, 296 pages, published as CERN Yellow Report https://cds.cern.ch/record/1406310

Non-relativistic high-energy physics: top production and dark matter annihilation

Beneke, Martin; Steinhauser, Matthias
Tipo: Artigo de Revista Científica
Publicado em 26/06/2015 Português
Relevância na Pesquisa
96.96304%
Non-relativistic physics is often associated with atomic physics and low-energy phenomena of the strong interactions between nuclei and quarks. In this review we cover three topics in contemporary high-energy physics at or close to the TeV scale, where non-relativistic dynamics plays an important if not defining role. We first discuss in detail the third-order corrections to top-quark pair production in electron-positron collisions in the threshold region, which plays a major role at a future high-energy e+ e- collider. Threshold effects are also relevant in the production of heavy particles in hadronic collisions, where in addition to the Coulomb force soft gluon radiation contributes to enhanced quantum corrections. We review the joint resummation of non-relativistic and soft gluon effects for pair production of top quarks and supersymmetric particles to next-to-next-to-leading logarithmic accuracy. The third topic deals with pair annihilation of dark matter particles within the framework of the Minimal Supersymmetric Standard Model. Here the electroweak Yukawa force generated by the exchange of gauge and Higgs bosons can cause large "Sommerfeld" enhancements of the annihilation cross section in some parameter regions.; Comment: 36 pages...

HEPMath 1.4: A Mathematica Package for Semi-Automatic Computations in High Energy Physics

Wiebusch, Martin
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
96.89719%
This article introduces the Mathematica package \emph{HEPMath} which provides a number of utilities and algorithms for High Energy Physics computations in Mathematica. Its functionality is similar to packages like FormCalc or FeynCalc, but it takes a more complete and extensible approach to implementing common High Energy Physics notations in the Mathematica language, in particular those related to tensors and index contractions. It also provides a more flexible method for the generation of numerical code which is based on new features for C code generation in Mathematica. In particular it can automatically generate Python extension modules which make the compiled functions callable from Python, thus eliminating the need to write any code in a low-level language like C or Fortran. It also contains seamless interfaces to LHAPDF, FeynArts, and LoopTools.

The interplay between high energy physics and cosmology: an example

Tipo: Artigo de Revista Científica
Publicado em 09/02/2005 Português
Relevância na Pesquisa
96.9298%
Cosmology and high energy physics are two closely connected areas. In this lecture I present an example of their rich interplay.; Comment: Invited talk at the DPU workshop: The density fluctuations in the Universe: Beyond the inflationary paradigm (Dimokritos, Athens 2004) (see http://physics.ntua.gr/dpu/). 8 two column pages

Bell Inequalities in High Energy Physics

Ding, Yi-Bing; Li, Junli; Qiao, Cong-Feng
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
96.9298%
We review in this paper the research status on testing the completeness of Quantum mechanics in High Energy Physics, especially on the Bell Inequalities. We briefly introduce the basic idea of Einstein, Podolsky, and Rosen paradox and the results obtained in photon experiments. In the tests of Bell inequalities in high energy physics, the early attempts of using spin correlations in particle decays and later on the mixing of neutral mesons used to form the quasi-spin entangled states are covered. The related experimental results in K^0 and B^0 systems are presented and discussed. We introduce the new scheme, which is based on the non-maximally entangled state and proposed to implement in \phi factory, in testing the Local Hidden Variable Theory. And, we also discuss the possibility in generalizing it to the tau charm factory.; Comment: 26 pages, 3 eps figures; references added, published version

Quarkonium at the Frontiers of High Energy Physics: A Snowmass White Paper

Bodwin, Geoffrey T.; Braaten, Eric; Eichten, Estia; Olsen, Stephen Lars; Pedlar, Todd K.; Russ, James
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
96.96304%
In this Snowmass White Paper, we discuss physics opportunities involving heavy quarkonia at the intensity and energy frontiers of high energy physics. We focus primarily on two specific aspects of quarkonium physics for which significant advances can be expected from experiments at both frontiers. The first aspect is the spectroscopy of charmonium and bottomonium states above the open-heavy-flavor thresholds. Experiments at e^+ e^- colliders and at hadron colliders have discovered many new, unexpected quarkonium states in the last 10 years. Many of these states are surprisingly narrow, and some have electric charge. The observations of these charged quarkonium states are the first definitive discoveries of manifestly exotic hadrons. These results challenge our understanding of the QCD spectrum. The second aspect is the production of heavy quarkonium states with large transverse momentum. Experiments at the LHC are measuring quarkonium production with high statistics at unprecedented values of p_T. Recent theoretical developments may provide a rigorous theoretical framework for inclusive production of quarkonia at large p_T. Experiments at the energy frontier will provide definitive tests of this framework. Experiments at the intensity frontier also provide an opportunity to understand the exclusive production of quarkonium states.; Comment: 43 pages...

Proceedings of the 1st Asia-Europe-Pacific School of High-Energy Physics (AEPSHEP 12), Fukuoka, Japan, 14 - 27 Oct 2012

Kawagoe, K.; Mulders, M.
Tipo: Artigo de Revista Científica
Publicado em 07/07/2014 Português
Relevância na Pesquisa
97.00554%
The Asia-Europe-Pacific School of High-Energy Physics is intended to give young physicists an introduction to the theoretical aspects of recent advances in elementary particle physics. These proceedings contain lectures on quantum field theory, quantum chromodynamics, flavour physics and CP-violation, physics beyond the Standard Model, neutrino physics, particle cosmology, heavy-ion physics, as well as a presentation of recent results from the Large Hadron Collider (LHC), practical statistics for particle physicists and a short introduction to the principles of particle physics instrumentation.; Comment: 8 lectures, 285 pages, published as CERN Yellow Report https://cds.cern.ch/record/1443909

A New Era in High-energy Physics

Ahn, Eun-Joo; Cavaglia, Marco
Tipo: Artigo de Revista Científica
Publicado em 15/05/2002 Português
Relevância na Pesquisa
96.99851%
In TeV-scale gravity, scattering of particles with center-of-mass energy of the order of a few TeV can lead to the creation of nonperturbative, extended, higher-dimensional gravitational objects: Branes. Neutral or charged, spinning or spinless, Einsteinian or supersymmetric, low-energy branes could dramatically change our picture of high-energy physics. Will we create branes in future particle colliders, observe them from ultra high energy cosmic rays, and discover them to be dark matter?; Comment: 8 pages, 2 figures. Essay submitted on Mar 26, 2002 to the Gravity Research Foundation. Awarded the third prize in the 2002 GRF competition

Perspectives in High Energy Physics

Rajasekaran, G.
Tipo: Artigo de Revista Científica
Publicado em 26/08/1997 Português
Relevância na Pesquisa
96.89719%
A broad survey of High Energy Physics (HEP) both within as well as beyond the Standard Model is presented emphasizing the unsolved problems. Inspite of the spectacular success of the Standard Model, there is a serious crisis facing the field. The importance of research on new methods of acceleration that can resolve this crisis by taking us to superhigh energies is stressed. We briefly review the status of HEP in India and offer suggestions for the future.; Comment: LaTeX, 13 pages

Methods of Minimization of Calculations in High Energy Physics: 2. Minimization of number of vectors in problem

Bondarev, Alexander L.
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
96.89719%
The various ways to reduce number of vectors describing condition of particles for high energy physics problems are presented. In particular decomposition of any vector with respect to the basis, consisting of any four linearly independent vectors, including the orthonormal basis; construction of orthonormal bases from vectors of a problem; expression of one vector of problem through other is considered.; Comment: 9 pages, LaTeX

Signatures of very high energy physics in the squeezed limit of the bispectrum (violation of Maldacena's condition)

Chialva, Diego
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
96.95337%
We investigate the signatures in the squeezed limit of the primordial scalar bispectrum due to modifications of the standard theory at high energy. In particular, we consider the cases of modified dispersion relations and/or modified initial quantum state (both in the Boundary Effective Field Theory and in the New Physics Hyper-Surface formulations). Using the in-in formalism we study in details the squeezed limit of the contributions to the bispectrum from all possible cubic couplings in the effective theory of single-field inflation. We find general features such as enhancements and/or non-local shape of the non-Gaussianities, which are relevant, for example, for measurements of the halo bias and which distinguish these scenarios from the standard one (with Bunch-Davies vacuum as initial state and standard kinetic terms). We find that the signatures change according to the magnitude of the scale of new physics, and therefore several pieces of information regarding high energy physics could be obtained in case of detection of these signals, especially bounds on the scales of new physics.; Comment: 37 pages plus bibliography, version matching the one accepted for publication by JCAP. Increased pedagogical comments, improved presentation and text...

A pedagogical introduction to quantum integrability, with a view towards theoretical high-energy physics

Lamers, J.
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
96.97118%
These are lecture notes of an introduction to quantum integrability given at the Tenth Modave Summer School in Mathematical Physics, 2014, aimed at PhD candidates and junior researchers in theoretical physics. We introduce spin chains and discuss the coordinate Bethe ansatz (CBA) for a representative example: the Heisenberg XXZ model. The focus lies on the structure of the CBA and on its main results, deferring a detailed treatment of the CBA for the general $M$-particle sector of the XXZ model to an appendix. Subsequently the transfer-matrix method is discussed for the six-vertex model, uncovering a relation between that model and the XXZ spin chain. Equipped with this background the quantum inverse-scattering method (QISM) and algebraic Bethe ansatz (ABA) are treated. We emphasize the use of graphical notation for algebraic quantities as well as computations. Finally we turn to quantum integrability in the context of theoretical high-energy physics. We discuss factorized scattering in two-dimensional QFT, and conclude with a qualitative introduction to one current research topic relating quantum integrability to theoretical high-energy physics: the Bethe/gauge correspondence.; Comment: 74 pages, 10 figures, 3 tables; v2: minor corrections

Some Methods of Minimization of Calculations in High Energy Physics

Bondarev, Alexander L.