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Related papers: From Thermodynamics to the Bound on Viscosity

200 papers

The shear viscosity is an important characterization of how a many-body system behaves like a fluid. We study the shear viscosity in a strongly interacting solvable model, consisting of coupled Sachdev-Ye-Kitaev (SYK) islands. As…

High Energy Physics - Theory · Physics 2020-07-01 Xian-Hui Ge , Shao-Kai Jian , Yi-Li Wang , Zhuo-Yu Xian , Hong Yao

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

We show that the second law of thermodynamics poses a restriction on how well we can discriminate between quantum states. By examining an ideal gas with a quantum internal degree of freedom undergoing a cycle based on a proposal by Asher…

Quantum Physics · Physics 2024-01-23 José Polo-Gómez

We study the asymtotic behavior of solutions to the two-dimensional stochasitc Navier-Stokes (SNS) equation in the small viscosity limit. The SNS equation is supplemented with no-slip boundary condition, in which a strong boundary layer…

Analysis of PDEs · Mathematics 2023-03-14 Ya-Guang Wang , Meng Zhao

We perform a global model-to-data comparison on Au+Au collisions at $\sqrt{s_{NN}}=200$ GeV and Pb+Pb collisions at $2.76$ TeV and $5.02$ TeV, using a 2+1D hydrodynamics model with the EKRT initial state and a shear viscosity over entropy…

High Energy Physics - Phenomenology · Physics 2018-11-06 Jussi Auvinen , Kari J. Eskola , Pasi Huovinen , Harri Niemi , Risto Paatelainen , Peter Petreczky

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 review the modern view of fluid dynamics as an effective low energy, long wavelength theory of many body systems at finite temperature. We introduce the concept of a nearly perfect fluid, defined by a ratio $\eta/s$ of shear viscosity to…

High Energy Physics - Phenomenology · Physics 2015-06-19 Thomas Schaefer

We calculate the shear viscosity over entropy density ratio $\eta/s$ in Yang--Mills theory from the Kubo formula using an exact diagrammatic representation in terms of full propagators and vertices using gluon spectral functions as external…

High Energy Physics - Phenomenology · Physics 2015-09-16 Nicolai Christiansen , Michael Haas , Jan M. Pawlowski , Nils Strodthoff

The essence of the second law of classical thermodynamics is the `entropy principle' which asserts the existence of an additive and extensive entropy function, S, that is defined for all equilibrium states of thermodynamic systems and whose…

Mathematical Physics · Physics 2007-05-23 Elliott H. Lieb , Jakob Yngvason

This work is to study the generalized second law (GSL) of thermodynamics in tachyon cosmology where the boundary of the universe is assumed to be enclosed by a dynamical apparent horizon. The model is constrained with the observational…

General Relativity and Quantum Cosmology · Physics 2016-06-08 H. Farajollahi , A. Ravanpak , H. Shojaie , M. Abolghasemi

Causal viscous hydrodynamic fits to experimental data for pion and kaon transverse momentum spectra from central Au+Au collisions at \sqrt{s_{NN}}=200 GeV are presented. Starting the hydrodynamic evolution at 1 fm/c and using small values…

Nuclear Theory · Physics 2008-11-26 Paul Romatschke

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

Bekenstein has presented evidence for the existence of a universal upper bound of magnitude $2\pi R/\hbar c$ to the entropy-to-energy ratio $S/E$ of an arbitrary {\it three} dimensional system of proper radius $R$ and negligible…

General Relativity and Quantum Cosmology · Physics 2011-03-02 Shahar Hod

The viscosity of hadronic matter is studied using a classical evaluation of the scattering angle and a quantum mechanical discussion based on phase shifts from a potential. Semi classical limits of the quantum theory are presented. A hard…

Nuclear Theory · Physics 2010-09-30 Aram Z. Mekjian

We consider 2d QFTs as relevant deformations of CFTs in the thermodynamic limit. Using causality and KPZ universality, we place a lower bound on the timescale characterizing the onset of hydrodynamics. The bound is determined parametrically…

High Energy Physics - Theory · Physics 2022-04-20 Luca V. Delacretaz , A. Liam Fitzpatrick , Emanuel Katz , Matthew T. Walters

The effect of a temperature dependent bulk viscosity to entropy density ratio~($\zeta/s$) along with a constant shear viscosity to entropy density ratio~($\eta/s$) on the space time evolution of the fluid produced in high energy heavy ion…

Nuclear Theory · Physics 2012-01-23 Victor Roy , A. K. Chaudhuri

Recently, there has been a considerable progress on the issue of the thermodynamic second law, which is known as the law of entropy increase or irreversibility. In particular, a novel symmetry known as the Gallavotti-Cohen symmetry is found…

Statistical Mechanics · Physics 2018-08-01 Hyunggyu Park

The pressure, and the energy and entropy densities are determined for the SU(3) gauge theory in $2 + 1$ dimensions from lattice Monte Carlo calculations in the interval $0.6 \leq T/T_c \leq 15$. The finite temperature lattices simulated…

High Energy Physics - Lattice · Physics 2008-11-26 P. Bialas , L. Daniel , A. Morel , B. Petersson

We demonstrate that the unitarity of quantum field theory, through the positivity of spectral functions, underlies thermodynamic irreversibility for a subsystem separated by a horizon, in direct analogy with the irreversibility of…

High Energy Physics - Theory · Physics 2026-01-06 G. Yu. Prokhorov

The thermodynamics is extented to spacetimes with spin-torsion density.Impplications to Einstein-Cartan-de Sitter inflationary phases are discussed.A relation between the spin-torsion density,entropy and temperature is presented.A lower…

General Relativity and Quantum Cosmology · Physics 2007-05-23 L. C. Garcia de Andrade