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Heisenberg's Uncertainty Relation and Bell Inequalities in High Energy Physics
Fonte: Universidade Cornell
Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 24/01/2011
Português
Relevância na Pesquisa
961.4255%
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
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High-energy physics and cosmological perturbations: observing new physics at large scales
Fonte: Universidade Cornell
Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 10/12/2013
Português
Relevância na Pesquisa
962.1753%
#High Energy Physics - Theory#Astrophysics - Cosmology and Nongalactic Astrophysics#General Relativity and Quantum Cosmology
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
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Correlation between radiation processes in silicon and long-time degradation of detectors for high energy physics experiments
Fonte: Universidade Cornell
Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 20/11/2006
Português
Relevância na Pesquisa
960.2061%
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
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Proceedings of the 2009 CERN-Latin-American School of High-Energy Physics, Recinto Quirama, Colombia, 15 - 28 March 2009
Fonte: Universidade Cornell
Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 28/10/2010
Português
Relevância na Pesquisa
963.83586%
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
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Silicon detectors for the next generation of high energy physics experiments: expected degradation
Fonte: Universidade Cornell
Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 31/12/2005
Português
Relevância na Pesquisa
962.2514%
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...
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Indian Contributions to High Energy Physics in the 20th Century
Fonte: Universidade Cornell
Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 07/02/2006
Português
Relevância na Pesquisa
964.6259%
#Physics - History and Philosophy of Physics#High Energy Physics - Phenomenology#High Energy Physics - Theory
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
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Citation Networks in High Energy Physics
Fonte: Universidade Cornell
Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
962.1753%
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
Link permanente para citações:
Proceedings of the 2012 European School of High-Energy Physics (ESHEP 2012), La Pommeraye, Anjou, France, 06-19 Jun 2012
Fonte: Universidade Cornell
Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 28/04/2015
Português
Relevância na Pesquisa
959.9618%
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
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Non-relativistic high-energy physics: top production and dark matter annihilation
Fonte: Universidade Cornell
Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 26/06/2015
Português
Relevância na Pesquisa
962.48305%
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...
Link permanente para citações:
HEPMath 1.4: A Mathematica Package for Semi-Automatic Computations in High Energy Physics
Fonte: Universidade Cornell
Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
960.3871%
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.
Link permanente para citações:
The interplay between high energy physics and cosmology: an example
Fonte: Universidade Cornell
Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 09/02/2005
Português
Relevância na Pesquisa
961.4255%
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
Link permanente para citações:
Bell Inequalities in High Energy Physics
Fonte: Universidade Cornell
Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
961.4255%
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
Link permanente para citações:
Quarkonium at the Frontiers of High Energy Physics: A Snowmass White Paper
Fonte: Universidade Cornell
Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
962.48305%
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...
Link permanente para citações:
Proceedings of the 1st Asia-Europe-Pacific School of High-Energy Physics (AEPSHEP 12), Fukuoka, Japan, 14 - 27 Oct 2012
Fonte: Universidade Cornell
Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 07/07/2014
Português
Relevância na Pesquisa
963.83586%
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
Link permanente para citações:
A New Era in High-energy Physics
Fonte: Universidade Cornell
Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 15/05/2002
Português
Relevância na Pesquisa
963.6121%
#High Energy Physics - Phenomenology#Astrophysics#General Relativity and Quantum Cosmology#High Energy Physics - Theory
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
Link permanente para citações:
Perspectives in High Energy Physics
Fonte: Universidade Cornell
Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 26/08/1997
Português
Relevância na Pesquisa
960.3871%
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
Link permanente para citações:
Methods of Minimization of Calculations in High Energy Physics: 2. Minimization of number of vectors in problem
Fonte: Universidade Cornell
Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
960.3871%
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
Link permanente para citações:
Signatures of very high energy physics in the squeezed limit of the bispectrum (violation of Maldacena's condition)
Fonte: Universidade Cornell
Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
962.1753%
#Astrophysics - Cosmology and Nongalactic Astrophysics#General Relativity and Quantum Cosmology#High Energy Physics - Theory
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...
Link permanente para citações:
A pedagogical introduction to quantum integrability, with a view towards theoretical high-energy physics
Fonte: Universidade Cornell
Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
962.74234%
#Mathematical Physics#High Energy Physics - Theory#Nonlinear Sciences - Exactly Solvable and Integrable Systems
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
Link permanente para citações:
Some Methods of Minimization of Calculations in High Energy Physics
Fonte: Universidade Cornell
Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 20/01/1997
Português
Relevância na Pesquisa
960.3871%
Two approaches to calculations' minimization in High Energy Physics are
considered. The first one is the method of covariant calculations for the
amplitudes of processes with polarized Dirac particles. The second one connects
with the possibility to reduce the expressions for the traces of products of
ten and more Dirac gamma-matrices.; Comment: 9 pages, LaTeX, talk presented at the XVIII Workshop on High Energy
Physics and Field Theory. Protvino, Russia, June 26-30,1995
Link permanente para citações: