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The stochastic process of equilibrium fluctuations, of a system with long range interactions

Freddy Bouchet
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Abstract

The relaxation towards equilibrium of systems with long range interactions is not yet fully understood. As a step towards such a comprehension, we propose the study of the dynamical equilibrium fluctuations in a model system with long range interaction. We compute analytically, from the microscopic dynamics, the autocorrelation function of the order parameter. From this result, we derive analytically a Fokker Planck equation which describes the stochastic process of the impulsion of a single particle in an equilibrium bath. The diffusion coefficient is explicitly computed.

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Freddy Bouchet. 2003-05-08. The stochastic process of equilibrium fluctuations, of a system with long range interactions. https://doi.org/10.1103/physreve.70.036113

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