{ "id": "2001.07794", "version": "v1", "published": "2020-01-21T22:03:59.000Z", "updated": "2020-01-21T22:03:59.000Z", "title": "Convergence to quasi-stationarity through Poincaré inequalities and Bakry-Emery criteria", "authors": [ "William Oçafrain" ], "comment": "22 pages", "categories": [ "math.PR" ], "abstract": "This paper aims to provide some tools coming from functional inequalities to deal with quasi-stationarity for absorbed Markov processes. First, it is shown how a Poincar\\'e inequality related to a suitable Doob transform entails exponential convergence of conditioned distributions to a quasi-stationary distribution in total variation and in $1$-Wasserstein distance. A special attention is paid to multi-dimensional diffusion processes, for which the aforementioned Poincar\\'e inequality is implied by an easier-to-check Bakry-\\'{E}mery condition depending on the right eigenvector for the sub-Markovian generator, which is not always known. Under additional assumptions on the potential, it is possible to bypass this lack of knowledge showing that exponential quasi-ergodicity is entailed by the classical Bakry-\\'{E}mery condition.", "revisions": [ { "version": "v1", "updated": "2020-01-21T22:03:59.000Z" } ], "analyses": { "keywords": [ "bakry-emery criteria", "quasi-stationarity", "doob transform entails exponential convergence", "suitable doob transform entails exponential", "poincare inequality" ], "note": { "typesetting": "TeX", "pages": 22, "language": "en", "license": "arXiv", "status": "editable" } } }