{ "id": "2011.04716", "version": "v1", "published": "2020-11-09T19:45:17.000Z", "updated": "2020-11-09T19:45:17.000Z", "title": "Local time for run and tumble particle", "authors": [ "Prashant Singh", "Anupam Kundu" ], "comment": "18 pages, 9 figures", "categories": [ "cond-mat.stat-mech" ], "abstract": "We investigate the local time $(T_{loc})$ statistics for a run and tumble particle in an one dimensional inhomogeneous medium. The inhomogeneity is introduced by considering the position dependent rate of the form $R(x) = \\gamma \\frac{|x|^{\\alpha}}{l^{\\alpha}}$ with $\\alpha \\geq 0$. For $\\alpha =0$, we derive the probability distribution of $T_{loc}$ exactly which is expressed as a series of $\\delta$-functions in which the coefficients can be interpreted as the probability of multiple revisits of the particle to the origin starting from the origin. For general $\\alpha$, we show that the typical fluctuations of $T_{loc}$ scale with time as $T_{loc} \\sim t^{\\frac{1+\\alpha}{2+\\alpha}}$ for large $t$ and their probability distribution possesses a scaling behaviour described by a scaling function which we have computed analytically. In the second part, we study the statistics of $T_{loc}$ till the RTP makes a first passage to $x=M~(>0)$. In this case also, we show that the probability distribution can be expressed as a series sum of $\\delta$-functions for all values of $\\alpha~(\\geq 0)$ with coefficients appearing from appropriate exit problems. All our analytical findings are supported with the numerical simulations.", "revisions": [ { "version": "v1", "updated": "2020-11-09T19:45:17.000Z" } ], "analyses": { "keywords": [ "local time", "tumble particle", "position dependent rate", "probability distribution possesses", "appropriate exit problems" ], "note": { "typesetting": "TeX", "pages": 18, "language": "en", "license": "arXiv", "status": "editable" } } }