{ "id": "1803.05646", "version": "v1", "published": "2018-03-15T09:05:23.000Z", "updated": "2018-03-15T09:05:23.000Z", "title": "Existence of (Markovian) solutions to martingale problems associated with Lévy-type operators", "authors": [ "Franziska Kühn" ], "categories": [ "math.PR" ], "abstract": "Let $A$ be a pseudo-differential operator with symbol $q(x,\\xi)$. In this paper we derive sufficient conditions which ensure the existence of a solution to the $(A,C_c^{\\infty}(\\mathbb{R}^d))$-martingale problem. If the symbol $q$ depends continuously on the space variable $x$, then the existence of solutions is well understood, and therefore the focus lies on martingale problems for pseudo-differential operators with discontinuous coefficients. We prove an existence result which allows us, in particular, to obtain new insights on the existence of weak solutions to a class of L\\'evy-driven SDEs with Borel measurable coefficients and on the the existence of stable-like processes with discontinuous coefficients. Moreover, we establish a Markovian selection theorem which shows that - under mild assumptions - the $(A,C_c^{\\infty}(\\mathbb{R}^d))$-martingale problem gives rise to a strong Markov process. The result applies, in particular, to L\\'evy-driven SDEs. We illustrate the Markovian selection theorem with applications in the theory of non-local operators and equations; in particular, we establish under weak regularity assumptions a Harnack inequality for non-local operators of variable order.", "revisions": [ { "version": "v1", "updated": "2018-03-15T09:05:23.000Z" } ], "analyses": { "subjects": [ "60J35" ], "keywords": [ "martingale problem", "lévy-type operators", "markovian selection theorem", "non-local operators", "pseudo-differential operator" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable" } } }