相关论文: Shear viscosity coefficient and relaxation time of…
The Green-Kubo-Nakano formula should be modified in relativistic hydrodynamics because of the problem of acausality and the breaking of sum rules. In this work, we propose a formula to calculate the transport coefficients of causal…
The microscopic formulae of the bulk viscosity $\zeta $ and the corresponding relaxation time $\tau_{\Pi}$ in causal dissipative relativistic fluid dynamics are derived by using the projection operator method. In applying these formulae to…
The microscopic formulas for the shear viscosity $\eta$, the bulk viscosity $\zeta$, and the corresponding relaxation times $\tau_\pi$ and $\tau_\Pi$ of causal dissipative relativistic fluid-dynamics are obtained at finite temperature and…
We investigate the microscopic origin of the relaxation time coefficient in relativistic fluid dynamics. We show that the extraction of the shear viscosity relaxation time via the gradient expansion is ambiguous and in general fails to give…
Transport coefficients of causal dissipative relativistic fluid dynamics (CDR) are studied in quenched lattice simulations. CDR describes the behavior of relativistic non-Newtonian fluids in which the relaxation time appears as a new…
In this paper we provide a quantum field theoretical study on the shear and bulk relaxation times. First, we find Kubo formulas for the shear and the bulk relaxation times, respectively. They are found by examining response functions of the…
The shear viscosity $\eta$ has been calculated by using the Green-Kubo relation in the framework of a partonic transport approach solved at cascade level. We compare the numerical results for $\eta$ obtained from the Green-Kubo correlator…
We calculate two transport coefficients -- the shear viscosity over entropy ratio $\eta/s$ and the ratio of the electric conductivity to the temperature $\sigma_0/T$ -- of strongly interacting quark matter within the extended $N_f=3$…
This is a comment to hep-th/0703243. The paper determined the relaxation time tau_pi of the shear viscous stress for the N=4 SYM from AdS/CFT correspondence. The purpose of this comment is to point out that the value of tau_pi is 3 times…
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…
We use a novel formulation of the relaxation time approximation to consistently calculate the bulk and shear viscosity coefficients using QCD-inspired energy-dependent relaxation times and phenomenological thermal masses obtained from fits…
We compute the shear viscosity of QCD with matter, including almost all next-to-leading order corrections -- that is, corrections suppressed by one power of $g$ relative to leading order. We argue that the still missing terms are small. The…
Starting from the Boltzmann equation in the relaxation time approximation and employing a Chapman-Enskog like expansion for the distribution function close to equilibrium, we derive second-order evolution equations for the shear stress…
Second-order dissipative hydrodynamic equations for each component of a multi-component system are derived using the entropy principle. Comparison of the solutions with kinetic transport results demonstrates validity of the obtained…
We study the shear mode in the gauge/gravity correspondence at finite temperature. First, we confirm the general formula for the shear viscosity in an arbitrary background metric which includes a black hole in the fifth dimension. We then…
We calculate the transport coefficient of hadronic matter in the presence of temperature and magnetic field using the linear sigma model. In the relaxation time approximation, we estimate the shear viscosity over entropy density $\eta/s$.…
Shear viscosity is a dynamical property of fluid systems close to equilibrium, describing resistance to sheared flow. After reviewing the physics of viscosity and the reason it is usually difficult to compute, I discuss its importance…
We argue that the ratio between the shear viscosity and the shear relaxation time, $\eta/\tau_\pi$, should be defined as a thermodynamic quantity obtained from the equal-time symmetric correlator of the shear-stress tensor. In kinetic…
The shear viscosity of a gluon gas is calculated using the Green-Kubo relation. Time correlations of the energy-momentum tensor in thermal equilibrium are extracted from microscopic simulations using a parton cascade solving various…
The relation of the shear viscosity coefficient to the recently introduced transport rate is derived within relativistic kinetic theory. We calculate the shear viscosity over entropy ratio \eta/s for a gluon gas, which involves elastic gg->…