Department of Physics Papers

Document Type

Journal Article

Date of this Version

5-9-2008

Comments

Suggested Citation:
G. Bunin, Y. Shokef, D. Levine. (2008). "Frequency-dependent fluctuation-dissipation relations in granular gases." Physical Review E. 77, 051301.

© 2008 The American Physical Society
http://dx.doi.org/10.1003/PhysRevE.77.051301.

Abstract

The Green-Kubo relation for two models of granular gases is discussed. In the Maxwell model in any dimension, the effective temperature obtained from the Green-Kubo relation is shown to be frequency independent and equal to the average kinetic energy, known as the granular temperature. In the second model analyzed, a mean-field granular gas, the collision rate of a particle is taken to be proportional to its velocity. The Green-Kubo relation in the high-frequency limit is calculated for this model, and the effective temperature in this limit is shown to be equal to the granular temperature. This result, taken together with previous results showing a difference between the effective temperature at zero frequency (the Einstein relation) and the granular temperature, shows that the Green-Kubo relation for granular gases is violated.

 

Date Posted: 25 January 2011

This document has been peer reviewed.