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	Quantum chromodynamics - Wikipedia, the free encyclopedia
		That QCD predicts this behavior was first discovered in the early 1970s by David Politzer and by Frank Wilczek and David Gross.
		The three kinds of charge in QCD (as opposed to one in QED) are usually referred to as "color charge" by loose analogy to the three kinds of color (red, green and blue) perceived by humans.
		QCD is a gauge theory of the SU(3) gauge group obtained by taking the color charge to define a local symmetry.
	en.wikipedia.org /wiki/Quantum_chromodynamics (1987 words)

	Encyclopedia topic: Lattice QCD (Site not responding. Last check: 2007-09-17)
		Lattice Quantum Chromodynamics (Lattice QCD) is the theory of quarks (Hypothetical truly fundamental particle in mesons and baryons; there are supposed to be six flavors of quarks (and their antiquarks), which come in pairs; each has an electric charge of +2/3 or -1/3) and gluons (A gauge boson that mediates strong interaction among quarks) formulated
		The formulation of quantum chromodynamics (A theory of strong interactions between elementary particles (including the interaction that binds protons and neutrons in the nucleus); it assumes that strongly interacting particles (hadrons) are made of quarks and that gluons bind the quarks together) on a discrete rather than continuous
		Most importantly, Lattice QCD provides the framework for investigating of non-perturbative phenomenas such as confinement (The state of being confined), which are intractable by means of analytic field theories.
	www.absoluteastronomy.com /encyclopedia/l/la/lattice_qcd2.htm (143 words)

	CERN Courier - Joining up the dots with the - IOP Publishing - article
		QCD is a key component of the Standard Model because any experiment aimed at the study of quark interactions must necessarily confront the issue that quarks are confined inside hadrons by the strong interactions of QCD.
		An important example of where lattice QCD calculations are needed is the attempt by experiments at B factories to test the self-consistency of the Standard Model through the determination of the elements of the Cabibbo-Kobayashi-Maskawa (CKM) matrix.
		Lattice QCD results are calculated for a lattice with a finite volume and a finite lattice spacing, but we want them to be relevant to the infinite volume and zero lattice spacing of the real world.
	cerncourier.com /main/article/44/5/13 (2064 words)

	Quantum chromodynamics Article, Quantumchromodynamics Information (Site not responding. Last check: 2007-09-17)
		Quantum Chromodynamics (QCD) is the physical theory describingone of the fundamental forces, the strong interaction.
		QCD is a non-perturbative theorydue to effects like confinement, fermion condensates and instantons.
		QCD lattice models have enabled researchers to obtaintheoretical results and quantities that were previously uncalculable.
	www.anoca.org /theory/qcd/quantum_chromodynamics.html (201 words)

	The Lattice Web (Site not responding. Last check: 2007-09-17)
		Lattice Quantum ChromoDynamics is a challenging computational field employing large scale numerical calculations to extract predictions of the Standard Model of nuclear physics, Quantum ChromoDynamics.
		Lattice Hadron Physics Collaboration, a part of USQCD collaboration with a focus on hadron structure.
		The Lattice QCD Archive at CP-PACS in Japan.
	www.lqcd.org (192 words)

	Research in Quarks, Hadrons and Nuclei: TQHN
		As a consequence, approximate lattice QCD calculations usually do not capture the low-energy physics associated with a cloud of pions on the periphery of a hadron.
		Typically, the pion mass is too large in the lattice simulations and the physics of the pion cloud is suppressed.
		Professor Wallace's current interest is in lattice QCD calculations for the mass spectrum of baryons and for hadron-hadron interactions.
	www.physics.umd.edu /tqhn/TQHN_research.html (1540 words)

	Lattice Gauge Theory & Quantum Chromodynamics: Physics on a 4D Scaffold (Site not responding. Last check: 2007-09-17)
		All these are described by a theory called Quantum Chromodyamics (QCD) in which the quarks and gluons (partons) are endowed with colour charges --- a generalisation of the electric charge in electromagnetism.
		Lattice QCD allows us to extract some information about the non-perturbative aspects of QCD and to predict characteristics of the strong nuclear force.
		The construction of Lattice QCD may be explained in a number of steps.
	www.ph.unimelb.edu.au /~ywong/poster/articles/latqcd2.html (537 words)

	ipedia.com: Quantum chromodynamics Article (Site not responding. Last check: 2007-09-17)
		Quantum Chromodynamics (QCD) is the physical theory describing one of the fundamental forces, the strong interaction.
		QCD is a non-perturbative theory due to effects like confinement, fermion condensates and instantons.
		QCD lattice models have enabled researchers to obtain theoretical results and quantities that were previously uncalculable.
	www.ipedia.com /quantum_chromodynamics.html (179 words)

	Life on the lattice: The life of a lattice tadpole
		At the end of the last post we saw that the bare coupling in lattice gauge theory is a bad coupling to do a perturbative expansion in.
		In lattice QCD, the matter fields are assigned to the sites of the lattice, and the gauge fields "live" on the links.
		Lattice QCD programs tend to be really simple in theri basic structure.
	latticeqcd.blogspot.com /2004/11/life-of-lattice-tadpole.html (1049 words)

	NERSC Annual Report 2002: HENP: Lattice QCD at Finite Isospin Density
		QCD at finite temperature and density describes the physics of the early Universe, neutron stars, heavy nuclei, and relativistic heavy ion collisions.
		x 24 lattice, allowing measurement of the mass of the Goldstone pion that this symmetry breaking implies, measurement of the spectrum of pseudo-Goldstone bosons, and confirmation of the nature of the transition.
		J. Kogut and D. Sinclair, “Lattice QCD at finite isospin density,” Nucl.
	www.nersc.gov /news/annual_reports/annrep02/45-QCD.html (185 words)

	Physics Today February 2004 - Article: Lattice Quantum Chromodynamics Comes of Age
		The gluon is the QCD analog of the photon; it carries the strong force between quarks.
		In 1974, Kenneth Wilson at Cornell University formulated a version of QCD on a discrete spacetime lattice (see the left panel of figure 1) and, with pencil and paper, used it to provide a plausible, but not rigorous, argument for color confinement.
		Because of its close relationship to statistical thermodynamics, lattice QCD in its current formulation is unsuited for simulating real-time processes such as multiparticle scattering and the nonequilibrium behavior of the QGP.
	www.physicstoday.org /pt/vol-57/iss-2/p45.html (3227 words)

	Starting from Square One: Science News Online, Aug. 7, 2004 (Site not responding. Last check: 2007-09-17)
		So, theorists using lattice QCD made compromises, such as portraying the properties of particles in deliberately incorrect ways that were more computationally friendly.
		This past year's precise lattice calculations indicate that such a method could be in the offing for B meson studies.
		For example, in modifying the staggering trick of lattice QCD, says Thomas A. DeGrand of the University of Colorado in Boulder, the technique's developers rely on a mathematical operation that may deny the local nature of space and time.
	www.sciencenews.org /articles/20040807/bob9.asp (2619 words)

	QCD and Lattice Field Theory in a Nutshell
		In QCD there is a field for each of the six quarks and for each of the eight gluons.
		For a simulation in QCD, the lattice spacing a is taken small compared to the size of a proton, so that discretization effects are small, while the number of lattice points is chosen sufficiently large that the `universe' created this way is larger than the proton size.
		The lattice formulation of a field theory therefore benefits greatly from the techniques developed in that area, in particular the Wilson renormalization group.
	www.scsc.ethz.ch /CPP/lft.html (851 words)

	Lattice QCD and Hadron Phenomenology
		The main subject of this program will be the application of lattice QCD, in conjunction with other systematic techniques, to the study of hadron phenomenology.
		We envisage the participants to be a mix of lattice QCD practitioners and hadron theorists with an interest in using results from, and contributing ideas to, lattice QCD.
		We aim to bring together researchers from three communities: lattice QCD (with research interests ranging from simulations to theoretical developments), nuclear theory, and particle theory.
	int.phys.washington.edu /PROGRAMS/INT-01-3prog.html (260 words)

	[No title] (Site not responding. Last check: 2007-09-17)
		Our objectives are to determine the position and nature of the phase transition from hadronic matter to a quark-gluon plasma from lattice quantum chromodynamics (QCD), to determine properties of hadrons from lattice QCD, and to improve lattice QCD methodology.
		QCD is simulated on a discrete space-time lattice (lattice QCD) by formulating it as a molecular dynamics problem and solving its "time" evolution numerically.
		We have probed the chiral nature of the QCD phase transition at finite temperature by studying the screening lengths for mesonic exitations in the hadronic matter and plasma phases.
	www.nersc.gov /news/annual_reports/annrep97/sinclair.html (333 words)

	Frank Lee's Research Interests
		Lattice QCD has evolved to the point that a large class of important problems in nuclear physics can be solved with adequate human and computer resources.
		Conventional QCD sum rule studies tend to fall short in the analysis stage where it is limited to only a small portion of the QCD parameter space, and often the uncertainties assigned to the fit parameters have a certain degree of arbitrariness.
		The QCD sum rules method is well-suited to the study of isospin symmetry breakings, since the contributions of the up and down quarks can be explicitly kept separate in each step of the calculation.
	home.gwu.edu /~fxlee/research.html (2556 words)

	Exploration of Hadron Structure and Spectroscopy using Lattice QCD (06-1)
		As a result of developments in lattice field theory and computer technology and of the investment by the DOE in lattice QCD facilities for the national community, the first full QCD calculations in the chiral regime are becoming available, opening a new era for confronting experiment with solutions of QCD from first principles.
		The focus will be twofold, both using lattice QCD to obtain insight into hadron structure and spectroscopy, and calculating observables that are relevant to current experiments and that will guide the future experimental program.
		Theorists directly involved in large scale lattice calculations will benefit greatly from extended interaction with phenomenologists who are interested in how lattice QCD can contribute to understanding hadron structure and testing phenomenological models and with theorists interested in chiral perturbation theory and renormalization.
	int.phys.washington.edu /PROGRAMS/06-1.html (775 words)

	Physics Papers
		One of the major frontiers of lattice field theory is the inclusion of light fermions in simulations, particularly in pursuit of accurate, first principles predictions from lattice QCD.
		The properties of the QCD phase transition are expected to depend on the degree of U_A(1) symmetry breaking in the transition region.
		QCD with eight flavors is studied on $16^3\times N_t$ lattices with $N_t=4$, 6, 8, 16 and 32, a dynamical quark mass $ma=0.015$ and lattice coupling $\beta=6/g^2$ between 4.5 and 5.0.
	phys.columbia.edu /~cqft/physics_papers.htm (1894 words)

	consensus
		This is a draft of the consensus statement as agreed upon by the members of the lattice QCD executive committee (R. Sugar (chair), N.
		White Paper written in 1999 by the Lattice QCD Executive Committee, in which a five-year plan for computing facilities for LQCD was enunciated.
		Lattice simulations of QCD can potentially answer a variety of physics questions crucial to the interpretation of experimental results from the high energy and nuclear physics programs.
	thy.phy.bnl.gov /www/qcdocworkshop.dir/consensus.html (685 words)

	4.3.1 Introduction
		Quantum chromodynamics (QCD) is the proposed theory of the so-called strong interactions that bind quarks and gluons together to form hadrons-the constituents of nuclear matter such as the proton and neutron.
		Most of the work on lattice QCD has been directed towards deriving the masses (and other properties) of the large number of hadrons, which have been found in experiments using high energy particle accelerators.
		One of the major problems in solving lattice QCD on a computer is that the simulation of the quark interactions requires the computation of a large, highly non-local matrix determinant, which is extremely compute-intensive.
	www.netlib.org /utk/lsi/pcwLSI/text/node34.html (474 words)

	Busstepp 2002 Lattice Field Theory
		Lattice Simulations and Effective Theories (C Sachrajda, Adv School on Eff Theories, Almunecar, Spain, 1995, hep-lat/9605027): introduction to the lattice formulation of quantum field theory, with applications to phenomenology (mostly b physics).
		Lattice Gauge Theory - A Short Primer (G Munster and M Walzl, ZUOZ 2000): introduction to the foundations and methods of lattice gauge theory (starting from the quantum mechanical path integral and moving on through functional integrals, Euclidean field theory and discretisation).
		Lattice QCD (C Davies): Lectures from the 2001 Scottish Universities' Summer School concentrating on applications to heavy quark physics (the topic of that school).
	www.hep.phys.soton.ac.uk /~jflynn/busstepp (565 words)

	1999 Summary of Engineering Research - Physics
		Other projects deal with applications of lattice QCD to phenomenologically interesting processes that yield insight into the standard model of particle physics.
		In the theory called quantum chromodynamics, observed particles such as the proton are composed of quarks, held together by forces transmitted by gluons, described by a nonabelian gauge field.
		New methods for dealing with fermions in lattice gauge theories have been developed by our group and are now being extensively exploited to study chiral symmetry restoration and quark deconfinement at finite temperatures and to study particle spectra.
	www.engr.uiuc.edu /Publications/engineering_research/1999/pg000216.htm (599 words)

	Computational Particle Physics, SCSC, ETH-Zurich
		The main topic of research is lattice Monte Carlo simulations of quantum chromodynamics (QCD), the theory of quarks and gluons.
		Simulations of lattice QCD use the Monte Carlo method, and new algorithms developed for lattice QCD can be applied to other problems of statistical mechanics or complex optimization.
		Similarly, lattice QCD makes heavy use of linear solvers, and is an appropriate ground to test the Numerical Algorithms group's new ideas.
	www.scsc.ethz.ch /CPP (275 words)

	Science News: Starting from square one: the intricate behavio... @ HighBeam Research (Site not responding. Last check: 2007-09-17)
		He had even invented a computational technique, called lattice QCD, to do just that Bemoaning the dearth of computing power available at the time, however, he concluded that his approach just wasn't worth pursuing.
		At a meeting on lattice QCD in June, Wilson offered to "pay penance for claiming in '86 that there was a long desert ahead."
		Lattice QCD explores the particle realm by taking a different tack It simulates quark and gluon behaviors by applying the full QCD theory to a tiny grid like facsimile of the space-time in which particles actually interact (SN: 1/6/96, p.
	www.highbeam.com /library/doc0.asp?DOCID=1G1:121208722&refid=holomed_1 (2472 words)

	Citebase - Lattice QCD
		A general introduction to lattice QCD suitable for graduate students in experimental and theoretical particle physics.
		Hein J et al, 2000, Scaling of the B and D meson spectrum in lattice QCD, Phys.
		Lepage P and Mackenzie P, 1993, On the viability of lattice perturbation theory, Phys.
	www.citebase.org /cgi-bin/citations?id=oai:arXiv.org:hep-ph/0205181 (1328 words)

	Citebase - Lattice QCD for RHIC
		When the free energy density of QCD is expanded in a series in the chemical potential, mu, the Taylor coefficients are the non-linear quark number susceptibilities.
		We have investigated the quark sector of quenched QCD for 1.5\le T/Tc\le3 in the continuum limit, using two different lattice discretisations of quarks and extrapolating from lattice spacings between 1/4T and 1/14T.
		Existing lattice data on the QCD phase transition are analyzed in renormalized perturbation theory.
	www.citebase.org /cgi-bin/citations?id=oai:arXiv.org:hep-ph/0212015 (1246 words)

	Life on the lattice
		One of the most interesting calculations in Lattice QCD is the determination of the strong coupling constant.
		Well, recall that QCD is perturbative at short distances, so if we measure a short distance quantity and have a perturbative expansion for it, we can solve for the coupling.
		Lattice QCD was invented in the mid-seventies by Kenneth Wilson.
	www.livejournal.com /~manobes (2464 words)

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