Author:F. Bonetto, G. Gallavotti, A. Giuliani, F. Zamponi

Title: Fluctuations relation and external thermostats: an application to granular materials
 
Abstract: In this note we discuss a paradigmatic example of interacting particles subject to non conservative external forces and to the action of thermostats consisting of external (finite) reservoirs of particles. We then consider a model of granular materials of interest for experimental tests that had recently attracted lot of attentions. This model can be reduced to the previously discussed example under a number of assumptions which can be expected to hold only on a specific time scale: as a result we predict a fluctuation relation for the entropy production rate measured on the same time scale.

Keywords: Granular Materials, Fluctuation Theorem, Nonequilibrium Themodynamics, Statistical mechanics, Chaos, Entropy, Irreversibility, Thermostats


Giovanni Gallavotti
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