Search results for "Gauge theory"

showing 6 items of 266 documents

Probing nucleons with photons at the quark level

2014

The description of electromagnetic interactions with hadrons from the quark level requires knowledge of the underlying quark-gluon ingredients. I discuss some properties of the quark-photon vertex and quark Compton vertex, along with the role of electromagnetic gauge invariance and vector-meson dominance. A simple parametrization for the quark-photon vertex is given.

Vertex (graph theory)PhysicsQuarkParticle physicsPhotonNuclear Theory010308 nuclear & particles physicsHigh Energy Physics::LatticeHadronNuclear TheoryHigh Energy Physics::PhenomenologyGeneral Physics and AstronomyFOS: Physical sciences01 natural sciencesNuclear Theory (nucl-th)High Energy Physics - PhenomenologyHigh Energy Physics - Phenomenology (hep-ph)0103 physical sciencesHigh Energy Physics::ExperimentVector mesonGauge theory010306 general physicsNucleonNuclear ExperimentParametrization
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Structure of longitudinal chromomagnetic fields in high energy collisions

2014

We compute expectation values of spatial Wilson loops in the forward light cone of high-energy collisions. We consider ensembles of gauge field configurations generated from a classical Gaussian effective action as well as solutions of high-energy renormalization group evolution with fixed and running coupling. The initial fields correspond to a color field condensate exhibiting domain-like structure over distance scales of order the saturation scale. At later times universal scaling emerges at large distances for all ensembles, with a nontrivial critical exponent. Finally, we compare the results for the Wilson loop to the two-point correlator of magnetic fields.

We compute expectation values of spatial Wilson loops in the forward light cone of high-energy collisions. We consider ensembles of gauge field configurations generated from a classical Gaussian effective action as well as solutions of high-energy renormalization group evolution with fixed and running coupling. The initial like structure over distance scales of oder the saturation scale. At later times universal scaling emerges at large distances for all ensembles with a nontrivial critical exponent. Finally we compare the resulats for the Wilson loop to the two-point correlator of magnetic fields. (C) 2014 The Authors. Published by Elsevier BV This is an open access article under the CC BY licenseNuclear and High Energy PhysicsWilson loopLARGE NUCLEINuclear TheoryField (physics)FOS: Physical sciences114 Physical sciences01 natural sciencesColor-glass condensateRENORMALIZATION-GROUPNuclear Theory (nucl-th)GLUON DISTRIBUTION-FUNCTIONSHigh Energy Physics - Phenomenology (hep-ph)Light cone0103 physical sciencesSCATTERINGGauge theory010306 general physicsSMALL-XEffective actionPhysicsCORRELATORSta114010308 nuclear & particles physicsCOLOR GLASS CONDENSATERenormalization groupEVOLUTIONJIMWLK EQUATIONHigh Energy Physics - PhenomenologySATURATIONQuantum electrodynamicsCritical exponentPhysics Letters B
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Determination of the non-abelian Debye screening mass using classical chromodynamics

2014

Tässä työssä tutkitaan gluonin Debye-massaa, ja sen aika- ja miehityslukudis- tribuutioriippuvuutta käyttäen klassista väridynamiikkaa kahdessa paikkaulot- tuvuudessa. Työssä tutkitaan myös ominaista liikemääräskaalaa ja miehitys- lukudistribuutioita. Gluonin Debye-massa määritetään sovittamalla suora glu- onien dispersiorelaatioon pienellä liikemäärällä. Tuloksia verrataan termisestä kenttäteoriasta johdetun kaavan ennusteisiin. Aluksi tutustutaan raskasionifysiikkaan liittyvään viitekehykseen. Tämän jälkeen kerrataan nopeasti klassinen Yang-Mills teoria jatkumossa ja hilalla. Käydään läpi Fourier kiihdytetty Coulombin mitan kiinnitysmenetelmä yk- sityiskohtaisesti jatkumossa ja hilalla. T…

high energy physics phenomenologygauge theorynon-abelian plasmalattice gauge theorynuclear theoryclassical chromodynamicsfysiikkaweak couplingnon-abelian lattice gauge theoryhigh energy physicsquark gluon plasma
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Topological Protection and Control of Quantum Markovianity

2020

This article belongs to the Special Issue Topological Photonics.

lcsh:Applied optics. PhotonicsDecoherence dynamicAnderson localizationQuantum-Hall topological insulatorQuantum decoherencePhysics::OpticsFOS: Physical sciences02 engineering and technologyTopology01 natural sciencesQuantum-Hall topological insulators0103 physical sciencesTopological orderRadiology Nuclear Medicine and imagingAnderson localizationGauge theoryQuantum information010306 general physicsInstrumentationQuantumNon-Markovianity in open quantum systemPhysicsQuantum PhysicsCavity quantum electrodynamicslcsh:TA1501-1820Decoherence dynamics021001 nanoscience & nanotechnologyAtomic and Molecular Physics and OpticsTopological orderQubitQuantum Physics (quant-ph)0210 nano-technologyNon-Markovianity in open quantum systemsPhotonics
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Highly occupied gauge theories in 2 + 1 dimensions : a self-similar attractor

2019

Motivated by the boost-invariant Glasma state in the initial stages in heavy-ion collisions, we perform classical-statistical simulations of SU(2) gauge theory in 2+1 dimensional space-time both with and without a scalar field in the adjoint representation. We show that irrespective of the details of the initial condition, the far-from-equilibrium evolution of these highly occupied systems approaches a unique universal attractor at high momenta that is the same for the gauge and scalar sectors. We extract the scaling exponents and the form of the distribution function close to this non-thermal fixed point. We find that the dynamics are governed by an energy cascade to higher momenta with sc…

quark-gluon plasmaScalar (mathematics)Adjoint representationhep-latFOS: Physical scienceshiukkasfysiikka114 Physical sciences01 natural sciencesComputer Science::Digital Librariessymbols.namesakeHigh Energy Physics - LatticeHigh Energy Physics - Phenomenology (hep-ph)Correlation functionfysikk0103 physical sciencesAttractorquantum chromodynamicsGauge theory010306 general physicsUNIVERSAL DYNAMICSParticle Physics - PhenomenologyMathematical physicsDebyePhysics:Matematikk og Naturvitenskap: 400::Fysikk: 430 [VDP]010308 nuclear & particles physicsHigh Energy Physics - Lattice (hep-lat)finite temperature field theoryParticle Physics - Latticehep-ph115 Astronomy Space scienceHigh Energy Physics - PhenomenologyDistribution functionsymbolsScalar fieldrelativistic heavy-ion collisions
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Quasiparticle properties of nonequilibrium gluon plasma

2018

We apply classical gluodynamics to early stages of ultrarelativistic heavy-ion collisions. We start by giving a brief overview of QCD. Then we proceed to the space-time evolution of ultrarelativistic heavy-ion collisions in the color glass condensate framework and go through the basics of real-time gluodynamics on the lattice in the temporal gauge. We study the plasmon mass scale in three- and two-dimensional systems by comparing three different methods to measure the mass scale. The methods are a formula which can be derived from Hard Thermal Loop effective theory at leading order (HTL), the effective dispersion relation (DR) and measurement of the plasma oscillation frequency triggered by th…

thermalizationnonequilibriumkvarkki-gluoniplasmalattice field theoryquasiparticleplasmon masshiukkasfysiikkahigh energy physicsclassical Yang-Mills theoryplasmonitplasmonquantum chromodynamicsnuclear theorylattice gauge theorykvanttiväridynamiikkakvanttikenttäteoriaclassical field theory
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