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Fluctuation relation for a Lévy particle

H. Touchette·E. G. D. Cohen
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Abstract

We study the work fluctuations of a particle subjected to a deterministic drag force plus a random forcing whose statistics is of the Lévy type. In the stationary regime, the probability density of the work is found to have ``fat'' power-law tails which assign a relatively high probability to large fluctuations compared with the case where the random forcing is Gaussian. These tails lead to a strong violation of existing fluctuation theorems, as the ratio of the probabilities of positive and negative work fluctuations of equal magnitude behaves in a non-monotonic way. Possible experiments that could probe these features are proposed.

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H. Touchette, E. G. D. Cohen. 2007-09-02. Fluctuation relation for a Lévy particle. https://doi.org/10.1103/physreve.76.020101

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