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arXiv · 2307.12816

Non-equilibrium memory effects: granular fluids and beyond

A Patrón·B. Sánchez-Rey·C. A. Plata·A. Prados
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Abstract

In this perspective paper, we look into memory effects in out-of-equilibrium systems. To be concrete, we exemplify memory effects with the paradigmatic case of granular fluids, although extensions to other contexts such as molecular fluids with non-linear drag are also considered. The focus is put on two archetypal memory effects: the Kovacs and Mpemba effects. In brief, the first is related to imperfectly reaching a steady state -- either equilibrium or non-equilibrium, whereas the second is related to reaching a steady state faster despite starting further. Connections to optimal control theory thus naturally emerge and are briefly discussed

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A Patrón, B. Sánchez-Rey, C. A. Plata, A. Prados. 2023-07-24. Non-equilibrium memory effects: granular fluids and beyond. https://doi.org/10.1209/0295-5075%2Facf7e5

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