{ "id": "2107.00760", "version": "v1", "published": "2021-07-01T22:10:55.000Z", "updated": "2021-07-01T22:10:55.000Z", "title": "Functional limit theorems for random walks perturbed by positive alpha-stable jumps", "authors": [ "Alexander Iksanov", "Andrey Pilipenko", "Oleksandr Prykhodko" ], "comment": "submitted for publication, 22 pages", "categories": [ "math.PR" ], "abstract": "Let $\\xi_1$, $\\xi_2,\\ldots$ be i.i.d. random variables of zero mean and finite variance and $\\eta_1$, $\\eta_2,\\ldots$ positive i.i.d. random variables whose distribution belongs to the domain of attraction of an $\\alpha$-stable distribution, $\\alpha\\in (0,1)$. The two collections are assumed independent. We consider a Markov chain with jumps of two types. If the present position of the Markov chain is positive, then the jump $\\xi_k$ occurs; if the present position of the Markov chain is nonpositive, then its next position is $\\eta_j$. We prove a functional limit theorem for this Markov chain under Donsker's scaling. The weak limit is a nonnegative process $(X(t))_{t\\geq 0}$ satisfying a stochastic equation ${\\rm d}X(t)={\\rm d}W(t)+ {\\rm d}U_\\alpha(L_X^{(0)}(t))$, where $W$ is a Brownian motion, $U_\\alpha$ is an $\\alpha$-stable subordinator which is independent of $W$, and $L_X^{(0)}$ is a local time of $X$ at $0$. Also, we explain that $X$ is a Feller Brownian motion with a `jump-type' exit from $0$.", "revisions": [ { "version": "v1", "updated": "2021-07-01T22:10:55.000Z" } ], "analyses": { "keywords": [ "functional limit theorem", "positive alpha-stable jumps", "markov chain", "random walks", "random variables" ], "note": { "typesetting": "TeX", "pages": 22, "language": "en", "license": "arXiv", "status": "editable" } } }