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Related papers: Shear Viscosity to Entropy within a Parton Cascade

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The present article has addressed the finite magnetic field extension of the previous work by Cho et al. (Phys. Rev. B 108, 235172, 2023) on microscopic calculation of shear viscosity for electron fluid in graphene system. Our calculation…

Strongly Correlated Electrons · Physics 2026-03-12 Cho Win Aung , Thandar Zaw Win , Subhalaxmi Nayak , Sabyasachi Ghosh

The shear viscosity of a two-component Fermi gas in the normal phase is calculated as a function of temperature in the unitarity limit, taking into account strong-coupling effects that give rise to a pseudogap in the spectral density for…

Statistical Mechanics · Physics 2008-11-26 G. M. Bruun , H. Smith

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

The shear viscosity coefficient and the corresponding relaxation time for causal dissipative hydrodynamics are calculated based on the microscopic formula proposed in [T. Koide and T. Kodama, Phys. Rev. \textbf{E 78}, 051107 (2008)]. Here,…

High Energy Physics - Theory · Physics 2009-09-02 T. Koide , E. Nakano , T. Kodama

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

Fast thermalization and a strong buildup of elliptic flow of QCD matter as found at RHIC are understood as the consequence of perturbative QCD (pQCD) interactions within the 3+1 dimensional parton cascade BAMPS. The main contributions stem…

High Energy Physics - Phenomenology · Physics 2009-06-16 I. Bouras , A. El , O. Fochler , J. Uphoff , Z. Xu , C. Greiner

The determination of the shear viscosity is a central topic in various areas of modern physics. In particular, it is often necessary to evaluate the shear viscosity $\eta$ of fluids made up of more than one species, all interacting with…

High Energy Physics - Phenomenology · Physics 2025-12-15 Gabriele Parisi , Vincenzo Nugara , Salvatore Plumari , Vincenzo Greco

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

We calculate shear viscosity to entropy density ratio in presence of four derivative (with coefficient $\alpha'$) and six derivative (with coefficient $\alpha'^2$) terms in bulk action. In general, there can be three possible four…

High Energy Physics - Theory · Physics 2009-07-22 Nabamita Banerjee , Suvankar Dutta

A theoretical framework for the calculation of shear and bulk viscosities of hadronic matter at finite temperature is presented. The framework is based on the quasi-particle picture. It allows for an arbitrary number of hadron species with…

Nuclear Theory · Physics 2011-02-01 P. Chakraborty , J. I. Kapusta

The elliptic flow $v_2$ and the ratio of the shear viscosity over the entropy density, $\eta/s$, of gluon matter are calculated from the perturbative QCD (pQCD) based parton cascade Boltzmann approach of multiparton scatterings. For Au+Au…

Nuclear Theory · Physics 2008-11-26 Zhe Xu , Carsten Greiner , Horst Stoecker

We calculate the shear viscosity and anomalous baryon number violation rate in quantum field theories at finite temperature having gravity duals with hyperbolic horizons. We find the explicit dependence of these quantities on the…

High Energy Physics - Theory · Physics 2015-05-13 George Koutsoumbas , Eleftherios Papantonopoulos , George Siopsis

The ratio eta/s, shear viscosity (eta) to entropy density (s), reaches its local minimum at the (second order) phase transition temperature in a wide class of systems. It was suspected that this behavior might be universal. However, a…

High Energy Physics - Phenomenology · Physics 2011-06-28 Jiunn-Wei Chen , Chang-Tse Hsieh , Han-Hsin Lin

We address a discrepancy between different computations of $\eta/s$ (shear viscosity over entropy density) of hadronic matter. Substantial deviations of this coefficient are found between transport approaches mainly based on resonance…

Nuclear Theory · Physics 2018-05-16 J. -B. Rose , J. M. Torres-Rincon , A. Schäfer , D. R. Oliinychenko , H. Petersen

Starting from a classical picture of shear viscosity we construct a stationary velocity gradient in a microscopic parton cascade. Employing the Navier-Stokes ansatz we extract the shear viscosity coefficient $\eta$. For elastic isotropic…

High Energy Physics - Theory · Physics 2013-05-30 Felix Reining , Ioannis Bouras , Andrej El , Chistian Wesp , Zhe Xu , Carsten Greiner

Shear viscosity $\eta$ is calculated for the nuclear matter described as a system of interacting nucleons with the van der Waals (VDW) equation of state. The Boltzmann-Vlasov kinetic equation is solved in terms of the plane waves of the…

Nuclear Theory · Physics 2016-11-30 A. G. Magner , M. I. Gorenstein , U. V. Grygoriev , V. A. Plujko

The shear viscosity for a moderately dense granular binary mixture of smooth hard spheres undergoing uniform shear flow is determined. The basis for the analysis is the Enskog kinetic equation, solved first analytically by the…

Statistical Mechanics · Physics 2009-11-10 Vicente Garzo , Jose Maria Montanero

We compute the shear viscosity of a superfluid atomic Fermi gas in the unitarity limit. The unitarity limit is characterized by a divergent scattering length between the atoms, and it has been argued that this will result in a very small…

Other Condensed Matter · Physics 2008-11-26 Gautam Rupak , Thomas Schaefer

We investigate the effects of baryon chemical potential \mu on the shear viscosity coefficient \eta and the viscosity to entropy density ratio \eta/s of a pion-nucleon gas mixture. We find that \eta is an increasing function of T and \mu,…

High Energy Physics - Phenomenology · Physics 2008-11-26 K. Itakura , O. Morimatsu , H. Otomo

Current experiments at the Relativistic Heavy Ion Collider (RHIC) are probing finite baryon densities where the shear viscosity to enthalpy ratio $\eta T/w$ of the Quark Gluon Plasma remains unknown. We use the Hadron Resonance Gas (HRG)…