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arXiv · 1804.09027

Active Brownian Motion in Two Dimensions

Urna Basu·Satya N. Majumdar·Alberto Rosso·Gregory Schehr
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Abstract

We study the dynamics of a single active Brownian particle (ABP) in two spatial dimensions. The ABP has an intrinsic time scale $D_R^{-1}$ set by the rotational diffusion constant $D_R$. We show that, at short-times $t \ll D_R^{-1}$, the presence of `activness' results in a strongly anisotropic and non-diffusive dynamics in the $(xy)$ plane. We compute exactly the marginal distributions of the $x$ and $y$ position coordinates along with the radial distribution, which are all shown to be non-Brownian. In addition, we show that, at early times, the ABP has anomalous first-passage properties, characterized by non-Brownian exponents.

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Urna Basu, Satya N. Majumdar, Alberto Rosso, Gregory Schehr. 2020-04-28. Active Brownian Motion in Two Dimensions. https://doi.org/10.1103/physreve.98.062121

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