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Related papers: Shear Viscosity to Entropy Density Ratio in Six De…

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The ratio of the shear viscosity to the entropy density is calculated for non-extremal Gauss-Bonnet (GB) black holes coupled to Born-Infeld (BI) electrodynamics in $5$ dimensions. The result is found to get corrections from the BI parameter…

High Energy Physics - Theory · Physics 2017-09-19 Saurav Das , Sunandan Gangopadhyay , Debabrata Ghorai

In this paper we calculate the ratio of transverse shear viscosity to entropy density for the general anisotropic black brane in Horava-Lifshitz gravity. There is a well-known conjecture that states this ratio should be larger than…

High Energy Physics - Theory · Physics 2019-06-27 Mehdi Sadeghi

We compute the strong coupling limit of the shear viscosity for the N=4 super-Yang-Mill theory with a chemical potential. We use the five-dimensional Reissner-Nordstrom-anti-deSitter black hole, so the chemical potential is the one for the…

High Energy Physics - Theory · Physics 2008-11-26 Kengo Maeda , Makoto Natsuume , Takashi Okamura

We calculate the ratio of shear viscosity to entropy density for a black brane of $5$-dimensional Einstein-Yang-Mills Gravity by Kubo and membrane paradigm methods. The former gives $\frac{1}{4\pi}$ exactly which is an expected result in…

High Energy Physics - Theory · Physics 2015-08-11 Mehdi Sadeghi , Shahrokh Parvizi

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

Starting from relativistic quantum field theories, Kovtun et al. (2005) have quite recently proposed a lower bound eta/s >= hbar /(4 pi kB), where eta is the shear viscosity and s the volume density of entropy for dense liquids. If their…

Statistical Mechanics · Physics 2009-02-15 G. G. N. Angilella , N. H. March , F. M. D. Pellegrino , R. Pucci

The well known shear viscosity to entropy density ratio ($\eta /s$) cannot be computed when the black hole space-time has zero thermodynamic entropy. This is the case, for example, when General Relativity in four dimensions is complemented…

High Energy Physics - Theory · Physics 2023-05-24 Moisés Bravo-Gaete , Luis Guajardo , Fabiano F. Santos

The transport coefficients of strongly interacting matter are currently subject of intense theoretical and phenomenological studies due to their relevance for the characterization of the quark-gluon plasma produced in ultra relativistic…

High Energy Physics - Phenomenology · Physics 2015-05-05 A. Puglisi , S. Plumari , V. Greco

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

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

In recent years, there has been a significant effort to extract the temperature-dependent shear ($\eta/s$) and bulk ($\zeta/s$) viscosity over entropy ratios of the quark-gluon plasma from a global comparison of heavy-ion data with results…

Nuclear Theory · Physics 2023-02-28 Fernando G. Gardim , Jean-Yves Ollitrault

In the framework of irreversible thermodynamics, we studied the transport properties of QGP. Shear viscosity and non-equilibrium entropy density related to viscous process at finite density has been investigated in weakly coupled limit by…

High Energy Physics - Phenomenology · Physics 2007-05-23 Hui Liu , Defu Hou , Jiarong Li

The ratio of shear viscosity to volume density of entropy can be used to characterize how close a given fluid is to being perfect. Using string theory methods, we show that this ratio is equal to a universal value of $\hbar/4\pi k_B$ for a…

High Energy Physics - Theory · Physics 2007-05-23 P. Kovtun , D. T. Son , A. O. Starinets

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

We calculate the ratio of shear viscosity to entropy density for charged black branes in third order Lovelock theory. For chargeless black branes, the result turns out to be consistent with the prediction made in $\rm arXiv:0808.3498[\rm…

High Energy Physics - Theory · Physics 2009-11-17 Xian-Hui Ge , Sang-Jin Sin , Shao-Feng Wu , Guo-Hong Yang

We have explored the shear viscosity and electrical conductivity calculations for bosonic and fermionic medium, which goes from without to with magnetic field picture and then their simplified massless expressions. In presence of magnetic…

High Energy Physics - Phenomenology · Physics 2020-10-12 Jayanta Dey , Sarthak Satapathy , Prasanta Murmu , Sabyasachi Ghosh

We consider an effective field theory description of beyond-quasi-particle excitations aiming to associate the transport properties of the system with the spectral density of states. Tuning various properties of the many-particle…

High Energy Physics - Phenomenology · Physics 2016-03-30 M. Horváth , A. Jakovác

Eighty years ago Eyring proposed that the shear viscosity of a liquid, $\eta$, has a quantum limit $\eta \gtrsim n\hbar$ where $n$ is the density of the fluid. Using holographic duality and the AdS/CFT correspondence in string theory…

Strongly Correlated Electrons · Physics 2015-09-30 Nandan Pakhira , Ross H. McKenzie

Nuclear multifragmentation in intermediate energy heavy ion collisions has long been associated with liquid-gas phase transition. We calculate the shear viscosity to entropy density ratio eta/s for an equilibrated system of nucleons and…

Nuclear Theory · Physics 2014-11-20 Subrata Pal

In this paper we consider a metric with hyperscaling violation on black brane background. In this background we calculate the ratio of shear viscosity to entropy density with hydrodynamics information. The calculation of this quantity lead…

High Energy Physics - Theory · Physics 2015-06-19 Jafar Sadeghi , Ali Asadi