Mode-coupling theory for the steady-state dynamics of active Brownian particles

Grzegorz Szamel

doi:10.1063/1.5085752

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arXiv · 1904.00804

Mode-coupling theory for the steady-state dynamics of active Brownian particles

Grzegorz Szamel

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Abstract

We present a theory for the steady-state dynamics of a two-dimensional system of spherically symmetric active Brownian particles. The derivation of the theory consists of two steps. First, we integrate out the self-propulsions and obtain a many-particle evolution equation for the probability distribution of the particles' positions. Second, we use projection operator technique and a mode-coupling-like factorization approximation to derive an equation of motion for the density correlation function. The nonequilibrium character of the active system manifests itself through the presence of a steady-state correlation function that quantifies spatial correlations of microscopic steady-state currents of the particles. This function determines the dependence of the short-time dynamics on the activity. It also enters into the expression for the memory matrix and thus influences the long-time glassy dynamics.

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Grzegorz Szamel. 2019-03-28. Mode-coupling theory for the steady-state dynamics of active Brownian particles. https://doi.org/10.1063/1.5085752

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