{ "id": "1604.08362", "version": "v1", "published": "2016-04-28T10:06:11.000Z", "updated": "2016-04-28T10:06:11.000Z", "title": "Asymptotic relation for the transition density of the three-dimensional Markov random flight on small time intervals", "authors": [ "Alexander D. Kolesnik" ], "comment": "19 pages, 5 figures", "categories": [ "math.PR" ], "abstract": "We consider the Markov random flight $\\bold X(t), \\; t>0,$ in the three-dimensional Euclidean space $\\Bbb R^3$ with constant finite speed $c>0$ and the uniform choice of the initial and each new direction at random time instants that form a homogeneous Poisson flow of rate $\\lambda>0$. Series representations for the conditional characteristic functions of $\\bold X(t)$ corresponding to two and three changes of direction, are obtained. Based on these results, an asymptotic formula, as $t\\to 0$, for the unconditional characteristic function of $\\bold X(t)$ is derived. By inverting it, we obtain an asymptotic relation for the transition density of the process. We show that the error in this formula has the order $o(t^3)$ and, therefore, it gives a good approximation on small time intervals whose lengths depend on $\\lambda$. Estimate of the accuracy of the approximation is analysed.", "revisions": [ { "version": "v1", "updated": "2016-04-28T10:06:11.000Z" } ], "analyses": { "subjects": [ "60K35", "60K99", "60J60", "60J65", "82C41", "82C70" ], "keywords": [ "three-dimensional markov random flight", "small time intervals", "asymptotic relation", "transition density", "unconditional characteristic function" ], "note": { "typesetting": "TeX", "pages": 19, "language": "en", "license": "arXiv", "status": "editable" } } }