{ "id": "1705.02830", "version": "v1", "published": "2017-05-08T11:25:47.000Z", "updated": "2017-05-08T11:25:47.000Z", "title": "Random time changes of Feller processes", "authors": [ "Franziska Kühn" ], "categories": [ "math.PR" ], "abstract": "We show that the SDE $dX_t = \\sigma(X_{t-}) \\, dL_t$, $X_0 \\sim \\mu$ driven by a one-dimensional symnmetric $\\alpha$-stable L\\'evy process $(L_t)_{t \\geq 0}$, $\\alpha \\in (0,2]$, has a unique weak solution for any continuous function $\\sigma: \\mathbb{R} \\to (0,\\infty)$ which grows at most linearly. Our approach relies on random time changes of Feller processes. We study under which assumptions the random-time change of a Feller process is a conservative $C_b$-Feller process and prove the existence of a class of Feller processes with decomposable symbols. In particular, we establish new existence results for Feller processes with unbounded coefficients. As a by-product, we obtain a sufficient condition in terms of the symbol of a Feller process $(X_t)_{t \\geq 0}$ for the perpetual integral $\\int_{(0,\\infty)} f(X_{s}) \\, ds$ to be infinite almost surely.", "revisions": [ { "version": "v1", "updated": "2017-05-08T11:25:47.000Z" } ], "analyses": { "subjects": [ "60J25", "60H10", "60G51", "60J75", "60J35", "60G44" ], "keywords": [ "feller process", "random time changes", "unique weak solution", "one-dimensional symnmetric", "stable levy process" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable" } } }