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arXiv · 1809.10656

Non-Gaussian noise without memory in active matter

Étienne Fodor·Hisao Hayakawa·Julien Tailleur·Frédéric van Wijland
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Abstract

Modeling the dynamics of an individual active particle invariably involves an isotropic noisy self-propulsion component, in the form of run-and-tumble motion or variations around it. This nonequilibrium source of noise is neither white---there is persistence---nor Gaussian. While emerging collective behavior in active matter has hitherto been attributed to the persistent ingredient, we focus on the non-Gaussian ingredient of self-propulsion. We show that by itself, that is without invoking any memory effect, it is able to generate particle accumulation close to boundaries and effective attraction between otherwise repulsive particles, a mechanism which generically leads to motility-induced phase separation in active matter.

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Étienne Fodor, Hisao Hayakawa, Julien Tailleur, Frédéric van Wijland. 2018-11-22. Non-Gaussian noise without memory in active matter. https://doi.org/10.1103/physreve.98.062610

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