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arXiv · 2204.09492

Simple fluid with broken time reversal invariance

Niklas Grimm·Annette Zippelius·Matthias Fuchs
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Abstract

We characterize a system of hard spheres with a simple collision rule that breaks time reversal symmetry, but conserves energy. The collisions lead to an a-chiral, isotropic, and homogeneous stationary state, whose properties are determined in simulations and compared to an approximate theory originally developed for elastic hard spheres. In the nonequilibrium fluid state, velocities are correlated, a phenomenon known from other nonequilibrium stationary states. The correlations are long-ranged decaying like $1/r^d$ in $d$ dimensions. Such correlations are expected on general grounds far from equilibrium and had previously been observed in driven or non-stationary systems.

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Niklas Grimm, Annette Zippelius, Matthias Fuchs. 2022-04-20. Simple fluid with broken time reversal invariance. https://doi.org/10.1103/physreve.106.034604

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