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Mesoscopic Theory of Critical Fluctuations in Isolated Granular Gases

J. Javier Brey·A. Dominguez·M. I. Garcia de Soria·P. Maynar
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Abstract

Fluctuating hydrodynamics is used to describe the total energy fluctuations of a freely evolving gas of inelastic hard spheres near the threshold of the clustering instability. They are shown to be governed by vorticity fluctuations only, that also lead to a renormalization of the average total energy. The theory predicts a power-law divergent behavior of the scaled second moment of the fluctuations, and a scaling property of their probability distribution, both in agreement with simulations results. A more quantitative comparison between theory and simulation for the critical amplitudes and the form of the scaling function is also carried out.

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BibTeXRIS

J. Javier Brey, A. Dominguez, M. I. Garcia de Soria, P. Maynar. 2005-11-24. Mesoscopic Theory of Critical Fluctuations in Isolated Granular Gases. https://doi.org/10.1103/physrevlett.96.158002

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