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Generalized fluctuation relation and effective temperatures in a driven fluid

F. Zamponi·G. Ruocco·L. Angelani
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Abstract

By numerical simulation of a Lennard-Jones like liquid driven by a velocity gradient γwe test the fluctuation relation (FR) below the (numerical) glass transition temperature T_g. We show that, in this region, the FR deserves to be generalized introducing a numerical factor X(T,γ)<1 that defines an ``effective temperature'' T_{FR}=T/X. On the same system we also measure the effective temperature T_{eff}, as defined from the generalized fluctuation-dissipation relation, and find a qualitative agreement between the two different nonequilibrium temperatures.

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BibTeXRIS

F. Zamponi, G. Ruocco, L. Angelani. 2005-01-20. Generalized fluctuation relation and effective temperatures in a driven fluid. https://doi.org/10.1103/physreve.71.020101

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