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arXiv · 1910.03302

Active hard-spheres in infinitely many dimensions

Thibaut Arnoulx de Pirey·Gustavo S. Lozano·Frédéric van Wijland
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Abstract

Few equilibrium --even less so nonequilibrium-- statistical-mechanical models with continuous degrees of freedom can be solved exactly. Classical hard-spheres in infinitely many space dimensions are a notable exception. We show that even without resorting to a Boltzmann distribution, dimensionality is a powerful organizing device to explore the stationary properties of active hard-spheres evolving far from equilibrium. In infinite dimensions, we compute exactly the stationary state properties that govern and characterize the collective behavior of active hard-spheres: the structure factor and the equation of state for the pressure. In turn, this allows us to account for motility-induced phase-separation. Finally, we determine the crowding density at which the effective propulsion of a particle vanishes.

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Thibaut Arnoulx de Pirey, Gustavo S. Lozano, Frédéric van Wijland. 2019-10-08. Active hard-spheres in infinitely many dimensions. https://doi.org/10.1103/physrevlett.123.260602

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