Scattering theory of Non-Brownian active particles with social distancing

Thomas Ihle; Rüdiger Kürsten; Benjamin Lindner

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arXiv · 2303.03354

Scattering theory of Non-Brownian active particles with social distancing

Thomas Ihle·Rüdiger Kürsten·Benjamin Lindner

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Abstract

We consider deterministic self-propelled particles with anti-alignment interactions. An asymptotically exact kinetic theory for particle scattering at low densities is constructed by a non-local closure of the BBGKY-hierarchy, involving pair correlations. We show that the mean-field assumption of molecular chaos yields unphysical predictions, whereas the scattering theory shows excellent agreement with agent-based simulations. To extend the theory to high densities, a self-consistent mapping to a random-telegraph process is performed. The approach is used to derive a one-particle Langevin-equation and leads to analytical expressions for the correlations of its effective noise.

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Thomas Ihle, Rüdiger Kürsten, Benjamin Lindner. 2023-03-06. Scattering theory of Non-Brownian active particles with social distancing. https://arxiv.org/abs/2303.03354

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