{ "id": "2006.06989", "version": "v1", "published": "2020-06-12T08:10:38.000Z", "updated": "2020-06-12T08:10:38.000Z", "title": "Universal Properties of a Run-and-Tumble Particle in Arbitrary Dimension", "authors": [ "Francesco Mori", "Pierre Le Doussal", "Satya N. Majumdar", "Gregory Schehr" ], "comment": "34 pages, 18 figures. This is an extended version of arXiv:2001.01492, published in Physical Review Letters", "categories": [ "cond-mat.stat-mech" ], "abstract": "We consider an active run-and-tumble particle (RTP) in $d$ dimensions, starting from the origin and evolving over a time interval $[0,t]$. We examine three different models for the dynamics of the RTP: the standard RTP model with instantaneous tumblings, a variant with instantaneous runs and a general model in which both the tumblings and the runs are non-instantaneous. For each of these models, we use the Sparre Andersen theorem for discrete-time random walks to compute exactly the probability that the $x$ component does not change sign up to time $t$, showing that it does not depend on $d$. As a consequence of this result, we compute exactly other $x$-component properties, namely the distribution of the time of the maximum and the record statistics, showing that they are universal, i.e. they do not depend on $d$. Moreover, we show that these universal results hold also if the speed $v$ of the particle after each tumbling is random, drawn from a generic probability distribution. Our findings are confirmed by numerical simulations. Some of these results have been announced in a recent Letter [Phys. Rev. Lett. 124, 090603 (2020)].", "revisions": [ { "version": "v1", "updated": "2020-06-12T08:10:38.000Z" } ], "analyses": { "keywords": [ "run-and-tumble particle", "arbitrary dimension", "universal properties", "universal results hold", "standard rtp model" ], "note": { "typesetting": "TeX", "pages": 34, "language": "en", "license": "arXiv", "status": "editable" } } }