Breakdown of fluctuation-dissipation relations in granular gases

Autor: Brey, J. J., de Soria, M. I. Garcia, Maynar, P.
Rok vydání: 2008
Předmět:
Druh dokumentu: Working Paper
DOI: 10.1209/0295-5075/84/24002
Popis: 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.
Comment: 9 pages, 4 figures
Databáze: arXiv