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Related papers: Shear Viscosity in a Gluon Gas

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We study the transport properties of strongly interacting matter in the context of ultrarelativistic heavy ion collision experiments. We calculate the transport coefficients viz. shear viscosity ($\eta$) and electrical conductivity…

High Energy Physics - Phenomenology · Physics 2017-06-01 Lata Thakur , P. K. Srivastava , Guru Prakash Kadam , Manu George , Hiranmaya Mishra

We calculate the shear viscosity over entropy density ratio $\eta/s$ in Yang--Mills theory from the Kubo formula using an exact diagrammatic representation in terms of full propagators and vertices using gluon spectral functions as external…

High Energy Physics - Phenomenology · Physics 2015-09-16 Nicolai Christiansen , Michael Haas , Jan M. Pawlowski , Nils Strodthoff

Hydrodynamics and collision dominated transport are crucial to understand the slow dynamics of many correlated quantum liquids. The ratio \eta/s of the shear viscosity \eta to the entropy density s is uniquely suited to determine how…

Mesoscale and Nanoscale Physics · Physics 2009-07-14 Markus Mueller , Joerg Schmalian , Lars Fritz

Shear and bulk viscosities of deconfined gluonic matter are investigated within an effective kinetic theory by describing the strongly interacting medium phenomenologically in terms of quasiparticle excitations with medium-dependent…

High Energy Physics - Phenomenology · Physics 2011-09-16 M. Bluhm , B. Kampfer , K. Redlich

Shear viscosity measures the amount of internal friction in a simple fluid. In kinetic theory shear viscosity is related to momentum transport by quasi-particles, and the uncertainty relation implies that the ratio of shear viscosity eta to…

Fluid Dynamics · Physics 2010-01-15 Thomas Schaefer

Shear viscosity is a measure of the amount of dissipation in a simple fluid. In kinetic theory shear viscosity is related to the rate of momentum transport by quasi-particles, and the uncertainty relation suggests that the ratio of shear…

High Energy Physics - Phenomenology · Physics 2009-11-18 Thomas Schaefer , Derek Teaney

We have investigated, in the frame work of the transport approach, different aspects of the QGP created in Heavy Ion Collisions at RHIC and LHC energies. The shear viscosity $\eta$ has been calculated by using the Green-Kubo relation at the…

High Energy Physics - Phenomenology · Physics 2015-06-11 Salvatore Plumari , Armando Puglisi , Maria Colonna , Francesco Scardina , Vincenzo Greco

The ratio of bulk to shear viscosity is expected to exhibit a different behaviour in weakly and in strongly coupled systems. This can be expressed by its dependence on the squared sound velocity. In the high temperature QCD plasma at small…

High Energy Physics - Phenomenology · Physics 2015-05-27 M. Bluhm , B. Kampfer , K. Redlich

Shear and bulk viscosity-to-entropy density ratios are calculated for the pure gluon matter in a non-equilibrium mean-field quasiparticle approach within the relaxation time approximation. We study how different approximations used in the…

Nuclear Theory · Physics 2011-09-22 A. S. Khvorostukhin , V. D. Toneev , D. N. Voskresensky

We compute the shear viscosity of two-flavor QCD plasma in an external magnetic field in perturbative QCD at leading log order, assuming that the magnetic field is weak or soft: $eB\sim g^4\log(1/g)T^2$. We show that the shear viscosity…

High Energy Physics - Phenomenology · Physics 2018-04-04 Shiyong Li , Ho-Ung Yee

We compute the shear viscosity of the unitary Fermi gas above the superfluid transition temperature, using a diagrammatic technique that starts from the exact Kubo formula. The formalism obeys a Ward identity associated with scale…

Quantum Gases · Physics 2011-02-01 Tilman Enss , Rudolf Haussmann , Wilhelm Zwerger

We investigate bulk and shear viscosities of the gluon plasma within relaxation time approximation to an effective Boltzmann-Vlasov type kinetic theory by viewing the plasma as describable in terms of quasigluon excitations with temperature…

High Energy Physics - Phenomenology · Physics 2015-05-20 M. Bluhm , B. Kampfer , K. Redlich

We study the ratio of bulk to shear viscosity in gluodynamics within a phenomenological quasiparticle model. We show that at large temperatures this ratio exhibits a quadratic dependence on the conformality measure as known from weak…

High Energy Physics - Phenomenology · Physics 2015-05-30 M. Bluhm , B. Kampfer , K. Redlich

We calculate the shear (eta) and bulk (zeta) viscosities of a weakly coupled quark gluon plasma at the leading-log order with finite temperature T and quark chemical potential mu. We find that the shear viscosity to entropy density ratio…

High Energy Physics - Phenomenology · Physics 2013-05-30 Jiunn-Wei Chen , Yen-Fu Liu , Yu-Kun Song , Qun Wang

Through model-to-data comparisons from heavy-ion collisions, it has been shown that the Quark Gluon Plasma has an extremely small shear viscosity at vanishing densities. At large baryon densities, significantly less is known about the…

High Energy Physics - Phenomenology · Physics 2025-06-12 Isabella Danhoni , Jordi Salinas San Martin , Jacquelyn Noronha-Hostler

Elliptic flow measurements at RHIC suggest that quark gluon plasma flows with very little viscosity compared to weak coupling expectations, challenging theorists to explain why this fluid is so nearly ``perfect''. It is therefore vital to…

Nuclear Theory · Physics 2009-11-11 Sean Gavin , Mohamed Abdel-Aziz

We propose a method for extracting the shear viscosity over entropy density ratio (eta/s) of the quark-gluon plasma from experimental data. We argue that uncertainty due to poor knowledge of the earliest stages of a heavy-ion collision is…

Nuclear Theory · Physics 2013-05-14 Matthew Luzum , Jean-Yves Ollitrault

We argue that the phenomenologically inferred ratio of shear viscosity to entropy density of the quark-gluon plasma, $\eta/\s < 0.5$ near the deconfinement temperature $T_c$, can be understood from perturbative QCD. To rebut the widespread,…

High Energy Physics - Phenomenology · Physics 2017-04-24 Greg Jackson , Andre Peshier

The shear ($\eta$) and bulk ($\zeta$) viscosities are calculated in a quasiparticle relaxation time approximation. The hadron phase is described within the relativistic mean field based model with scaled hadron masses and couplings. The…

Nuclear Theory · Physics 2010-10-19 A. S. Khvorostukhin , V. D. Toneev , D. N. Voskresensky

We compute the shear viscosity, $\eta$, at general temperatures $T$, in a BCS-BEC crossover scheme which is demonstrably consistent with conservation laws. The study of $\eta$ is important because it constrains microscopic theories by…

Quantum Gases · Physics 2011-08-04 H. Guo , D. Wulin , C. C. Chien , K. Levin