{ "id": "0911.4347", "version": "v2", "published": "2009-11-23T20:26:28.000Z", "updated": "2010-09-06T16:59:19.000Z", "title": "A General Duality Theorem for the Monge--Kantorovich Transport Problem", "authors": [ "Mathias Beiglboeck", "Christian Leonard", "Walter Schachermayer" ], "categories": [ "math.OC", "math.FA" ], "abstract": "The duality theory of the Monge--Kantorovich transport problem is analyzed in a general setting. The spaces $X, Y$ are assumed to be polish and equipped with Borel probability measures $\\mu$ and $\\nu$. The transport cost function $c:X\\times Y \\to [0,\\infty]$ is assumed to be Borel. Our main result states that in this setting there is no duality gap, provided the optimal transport problem is formulated in a suitably relaxed way. The relaxed transport problem is defined as the limiting cost of the partial transport of masses $1-\\varepsilon$ from $(X,\\mu)$ to $(Y, \\nu)$, as $\\varepsilon >0$ tends to zero. The classical duality theorems of H.\\ Kellerer, where $c$ is lower semi-continuous or uniformly bounded, quickly follow from these general results.", "revisions": [ { "version": "v2", "updated": "2010-09-06T16:59:19.000Z" } ], "analyses": { "subjects": [ "49Q20" ], "keywords": [ "monge-kantorovich transport problem", "general duality theorem", "borel probability measures", "optimal transport problem", "transport cost function" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2009arXiv0911.4347B" } } }