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arXiv · 1708.04259

How active forces influence nonequilibrium glass transitions

Ludovic Berthier·Elijah Flenner·Grzegorz Szamel
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Abstract

Dense assemblies of self-propelled particles undergo a nonequilibrium form of glassy dynamics. Physical intuition suggests that increasing departure from equilibrium due to active forces fluidifies a glassy system. We falsify this belief by devising a model of self-propelled particles where increasing departure from equilibrium can both enhance or depress glassy dynamics, depending on the chosen state point. We analyze a number of static and dynamic observables and suggest that the location of the nonequilibrium glass transition is primarily controlled by the evolution of two-point static density correlations due to active forces. The dependence of the density correlations on the active forces varies non-trivially with the details of the system, and is difficult to predict theoretically. Our results emphasize the need to develop an accurate liquid state theory for nonequilibrium systems.

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Ludovic Berthier, Elijah Flenner, Grzegorz Szamel. 2017-08-14. How active forces influence nonequilibrium glass transitions. https://doi.org/10.1088/1367-2630/aa914e

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