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Related papers: Shear Viscosity from Gauss-Bonnet Gravity with a D…

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We calculate the shear viscosity $\eta$ to entropy density $s$ ratio $\eta /s$ of a gluon plasma in kinetic theory including the gg->gg and gg<->ggg processes. Due to the suppressed contribution to $\eta$ in the gg->gg forward scattering,…

Nuclear Theory · Physics 2010-03-02 Jiunn-Wei Chen , Hui Dong , Kazuaki Ohnishi , Qun Wang

Using absorbance measurements through a Couette cell containing an emulsion of buoyant droplets, volume fraction profiles are measured at various shear rates. These viscous resuspension experiments allow a direct determination of the normal…

Soft Condensed Matter · Physics 2022-02-01 Mehdi Maleki , Clément de Loubens , Hugues Bodiguel

We investigate the temperature dependence of the shear viscosity and spin diffusion in a two-dimensional Fermi gas with contact interactions, as realized in ultra-cold atomic gases. We describe the transport coefficients in terms of a…

Quantum Gases · Physics 2012-07-16 Tilman Enss , Carolin Küppersbusch , Lars Fritz

We introduce the concept of viscosity (both shear and bulk) in the context of hadron physics and in particular the meson gas, highlighting the current theoretical efforts to connect possible measurements of the viscosities to underlying…

High Energy Physics - Phenomenology · Physics 2011-02-03 Antonio Dobado , Felipe J. Llanes-Estrada , Juan M. Torres-Rincon

We show that at the level of linear response the low frequency limit of a strongly coupled field theory at finite temperature is determined by the horizon geometry of its gravity dual, i.e. by the "membrane paradigm" fluid of classical…

High Energy Physics - Theory · Physics 2009-02-18 Nabil Iqbal , Hong Liu

We present a formulation of gravity in terms of a theory based on complex SU(2) gauge fields with a general coordinate invariant action functional quadratic in the field strength. Self-duality or anti-self-duality of the field strength…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Romesh K. Kaul

Using chiral perturbation theory we investigate the QCD shear viscosity to entropy density ratio below the deconfinement temperature (~170 MeV) with zero baryon number density. It is found that the viscosity to entropy density ratio of QCD…

High Energy Physics - Phenomenology · Physics 2008-11-26 Jiunn-Wei Chen , Eiji Nakano

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

Using the non-relativistic hydrodynamic expansion, we solve equations of motion for Einstein gravity and Gauss-Bonnet gravity with a negative cosmological constant within the region between a finite cutoff surface and a black brane horizon,…

High Energy Physics - Theory · Physics 2011-07-21 Rong-Gen Cai , Li Li , Yun-Long Zhang

We show that the generalized second law of thermodynamics may shed much light on the mysterious Kovtun-Son-Starinets (KSS) bound on the ratio of viscosity to entropy density. In particular, we obtain the lower bound $\eta/s…

High Energy Physics - Theory · Physics 2009-10-12 Shahar Hod

We analyze the main features of granular shear flow through experimental measurements in a Couette geometry and a comparison to a locally Newtonian, continuum model of granular flow. The model is based on earlier hydrodynamic models,…

Statistical Mechanics · Physics 2021-05-26 L. Bocquet , W. Losert , D. Schalk , T. C. Lubensky , J. P. Gollub

In higher dimensions, we study Degenerate-Higher-Order-Scalar-Tensor theories and we derive solutions that resemble the Schwarzschild Anti-de Sitter black holes. We compute their thermodynamic quantities following the Wald formalism,…

High Energy Physics - Theory · Physics 2022-10-05 Moisés Bravo-Gaete , Fabiano F. Santos , Henrique Boschi-Filho

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 show from covariant transport theory that, for a massless ideal gas equation of state, even a small shear viscosity to entropy density ratio $\eta \approx s/(4 \pi)$ generates significant 15-30% dissipative corrections to elliptic flow…

Nuclear Theory · Physics 2008-06-03 Denes Molnar

Viscous phenomena are the hallmark of the hydrodynamic flow exhibited by Dirac fermions in clean graphene at high enough temperatures. We report a quantitative calculation of the electronic shear and Hall viscosities in graphene based on…

Mesoscale and Nanoscale Physics · Physics 2019-07-31 B. N. Narozhny , M. Schütt

We compute the shear viscosity of the non-commutative N=4 super Yang-Mills quantum field theory at strong coupling using the dual supergravity background. Special interest derives from the fact that the background presents an intrinsic…

High Energy Physics - Theory · Physics 2009-04-17 Karl Landsteiner , Javier Mas

Gravitational effective theories are essential for characterizing the space of deviations from General Relativity (GR). Testing these theories against fundamental principles, such as causality and unitarity, can yield constraints on the…

High Energy Physics - Theory · Physics 2026-04-09 Alexander Cassem , Mark P. Hertzberg

It is known that the Minkowski vacuum appears as a thermal medium to an accelerated observer due to the renowned Unruh effect. More recently, it has been shown that at least for lower-spin fields this medium also exhibits a non-zero…

High Energy Physics - Theory · Physics 2026-05-22 R. V. Khakimov , G. Yu. Prokhorov , O. V. Teryaev

The Green-Kubo relation and fluctuation-dissipation theorem are employed to calculate the shear viscosity $\eta$ of a finite hot nucleus directly from the width and energy of the giant dipole resonance (GDR) of this nucleus. The ratio…

Nuclear Theory · Physics 2015-05-30 Nguyen Dinh Dang

We study the shear viscosity of a dilute Fermi gas as a function of the scattering length in the vicinity of the unitarity limit. The calculation is based on kinetic theory, which provides a systematic approach to transport properties in…

Quantum Gases · Physics 2014-12-17 Marcus Bluhm , Thomas Schaefer