A sticky business: the status of the conjectured viscosity/entropy density bound
High Energy Physics - Theory
2009-04-03 v2 Statistical Mechanics
High Energy Physics - Phenomenology
Nuclear Theory
Fluid Dynamics
Abstract
There have been a number of forms of a conjecture that there is a universal lower bound on the ratio, eta/s, of the shear viscosity, eta, to entropy density, s, with several different domains of validity. We examine the various forms of the conjecture. We argue that a number of variants of the conjecture are not viable due to the existence of theoretically consistent counterexamples. We also note that much of the evidence in favor of a bound does not apply to the variants which have not yet been ruled out.
Keywords
Cite
@article{arxiv.0708.4201,
title = {A sticky business: the status of the conjectured viscosity/entropy density bound},
author = {Aleksey Cherman and Thomas D. Cohen and Paul M. Hohler},
journal= {arXiv preprint arXiv:0708.4201},
year = {2009}
}
Comments
23 pages, 4 figures, added references, corrected typos, added subsection in response to Son's comments in arXiv:0709.4651