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Related papers: The Quantum Viscosity Bound In Lovelock Gravity

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We study the temperature dependence of the ratio of the shear viscosity to entropy density for the LQCD-contrasted hadron resonance gas of different finite system-sizes, which may represent the final state hadronic matter, formed in systems…

High Energy Physics - Phenomenology · Physics 2018-12-05 Nachiketa Sarkar , Premomoy Ghosh

We confirm and expand on work by Chafin and Schaefer on hydrodynamic fluctuations in the unitary Fermi gas. Using the result for the equation of state from a recent MIT experiment, we derive lower bounds for \eta/n and \eta/s as a function…

Quantum Gases · Physics 2013-05-17 Paul Romatschke , Ryan Edward Young

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 report a calculation of the shear viscosity in a relativistic multicomponent meson gas as a function of temperature and chemical potentials. We approximately solve the Uehling-Uhlenbeck transport equation of kinetic theory, appropriate…

High Energy Physics - Phenomenology · Physics 2009-11-10 Antonio Dobado , Felipe J. Llanes-Estrada

We investigate the shear viscosity $\eta$ and the entropy density $s$ of strongly coupled $\mathcal{N}=4$ super Yang-Mills (SYM) plasma in late time of hydrodynamic evolution with AdS/CFT duality and Bjorken scaling. We use correlation…

High Energy Physics - Phenomenology · Physics 2011-04-07 Shi Pu , Qun Wang

We solve the relativistic Riemann problem in viscous gluon matter employing a microscopic parton cascade. We demonstrate the transition from ideal to viscous shock waves by varying the shear viscosity to entropy density ratio $\eta/s$ from…

High Energy Physics - Phenomenology · Physics 2010-04-23 I. Bouras , E. Molnar , H. Niemi , Z. Xu , A. El , O. Fochler , C. Greiner , D. H. Rischke

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

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…

High Energy Physics - Phenomenology · Physics 2018-03-30 Jacopo Ghiglieri , Guy D. Moore , Derek Teaney

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

We estimate dissipative properties viz: shear and bulk viscosities of hadronic matter using relativistic Boltzmann equation in relaxation time approximation within ambit of excluded volume hadron resonance gas (EHRG) model. We find that at…

High Energy Physics - Phenomenology · Physics 2015-09-14 Guru Prakash Kadam , Hiranmaya Mishra

We determine the shear viscosity of the ultracold Fermi gas at unitarity in the normal phase using hydrodynamic expansion data. The analysis is based on a generalized fluid dynamic framework which ensures a smooth transition between the…

Quantum Gases · Physics 2017-08-16 Marcus Bluhm , Jiaxun Hou , Thomas Schaefer

We present an ab initio determination of the shear viscosity for the unitary Fermi gas based on finite temperature quantum Monte Carlo (QMC) calculations and the Kubo linear-response formalism. The results are confronted with the bound for…

Quantum Gases · Physics 2013-08-02 Gabriel Wlazłowski , Piotr Magierski , Aurel Bulgac , Kenneth J. Roche

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

Kovtun, Son and Starinets proposed a bound on the shear viscosity of any fluid in terms of its entropy density. We argue that this bound is always saturated for gauge theories at large 't Hooft coupling, which admit holographically dual…

High Energy Physics - Theory · Physics 2011-07-18 Alex Buchel , James T. Liu

We use gauge-gravity duality to compute entanglement entropy in a non-conformal background with an energy scale $\Lambda$. At zero temperature, we observe that entanglement entropy decreases by raising $\Lambda$. However, at finite…

High Energy Physics - Theory · Physics 2017-08-02 M. Rahimi , M. Ali-Akbari , M. Lezgi

Within gauge/gravity duality, we consider the AdS-Schwarzschild metric in arbitrary dimensions. We obtain analytical closed-form results for the two-point function, Wilson loop and entanglement entropy for strip geometries in the…

High Energy Physics - Theory · Physics 2018-04-04 Johanna Erdmenger , Nina Miekley

We discuss in detail the shear viscosity coefficient eta and the viscosity to entropy density ratio eta/s of a hadronic gas comprised of pions and nucleons. In particular, we study the effects of baryon chemical potential on eta and eta/s.…

High Energy Physics - Phenomenology · Physics 2008-11-26 Kazunori Itakura , Osamu Morimatsu , Hiroshi Otomo

In this contribution we summarize recent progress in understanding the shear viscosity of strongly correlated dilute Fermi gases. We discuss predictions from kinetic theory, and show how these predictions can be tested using recent…

Nuclear Theory · Physics 2015-05-20 Thomas Schaefer

We investigate the temperature dependence of the shear viscosity ($\eta$) and bulk viscosity ($\zeta$) of the gluon plasma using lattice QCD over the range 0.76--2.25$\,T_c$, extending from below the transition temperature $T_c$ across the…

High Energy Physics - Lattice · Physics 2026-04-08 Heng-Tong Ding , Hai-Tao Shu , Cheng Zhang

We study the shear and bulk viscosities of partonic and hadronic matter as functions of temperature T within the parton-hadron-string dynamics (PHSD) off-shell transport approach. Dynamical hadronic and partonic systems in equilibrium are…

High Energy Physics - Phenomenology · Physics 2015-06-12 V. Ozvenchuk , O. Linnyk , M. I. Gorenstein , E. L. Bratkovskaya , W. Cassing