A classical long-time tail in a driven granular fluid

W. Till Kranz

doi:10.1088/1742-5468/2014/02/p02010

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arXiv · 1308.3991

A classical long-time tail in a driven granular fluid

W. Till Kranz

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Abstract

I derive a mode-coupling theory for the velocity autocorrelation function, ψ(t), in a fluid of randomly driven inelastic hard spheres far from equilibrium. With this, I confirm a conjecture from simulations that the velocity autocorrelation function decays algebraically, ψ(t) ~ t^{-3/2}, if momentum is conserved. I show that the slow decay is due to the coupling to transverse currents.

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W. Till Kranz. 2013-08-19. A classical long-time tail in a driven granular fluid. https://doi.org/10.1088/1742-5468%2F2014%2F02%2Fp02010

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