Breakdown of fluctuation-dissipation relations in granular gases
Statistical Mechanics
2009-11-13 v1
Abstract
A numerical molecular dynamics experiment measuring the two-time correlation function of the transversal velocity field in the homogeneous cooling state of a granular gas is reported. By measuring the decay rate and the amplitude of the correlations, the accuracy of the Landau-Langevin equation of fluctuating hydrodynamics is checked. The results indicate that although a Langevin approach can be valid, the fluctuation-dissipation relation must be modified, since the viscosity parameter appearing in it differs from the usual hydrodynamic shear viscosity.
Cite
@article{arxiv.0804.2329,
title = {Breakdown of fluctuation-dissipation relations in granular gases},
author = {J. J. Brey and M. I. Garcia de Soria and P. Maynar},
journal= {arXiv preprint arXiv:0804.2329},
year = {2009}
}
Comments
9 pages, 4 figures