{ "id": "0904.1963", "version": "v3", "published": "2009-04-13T16:22:58.000Z", "updated": "2009-11-17T11:45:36.000Z", "title": "Continuity of the von Neumann entropy", "authors": [ "M. E. Shirokov" ], "comment": "42 pages, the minor changes have been made, the new applications of the continuity condition have been added. To appear in Commun. Math. Phys", "journal": "Commun. Math. Phys., vol. 296, no. 3, 625-654 (2010).", "categories": [ "math-ph", "math.MP", "quant-ph" ], "abstract": "A general method for proving continuity of the von Neumann entropy on subsets of positive trace-class operators is considered. This makes it possible to re-derive the known conditions for continuity of the entropy in more general forms and to obtain several new conditions. The method is based on a particular approximation of the von Neumann entropy by an increasing sequence of concave continuous unitary invariant functions defined using decompositions into finite rank operators. The existence of this approximation is a corollary of a general property of the set of quantum states as a convex topological space called the strong stability property. This is considered in the first part of the paper.", "revisions": [ { "version": "v3", "updated": "2009-11-17T11:45:36.000Z" } ], "analyses": { "keywords": [ "von neumann entropy", "continuity", "concave continuous unitary invariant functions", "strong stability property" ], "tags": [ "journal article" ], "publication": { "publisher": "Springer", "journal": "Communications in Mathematical Physics", "doi": "10.1007/s00220-010-1007-x", "year": 2010, "month": "Jun", "volume": 296, "number": 3, "pages": 625 }, "note": { "typesetting": "TeX", "pages": 42, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2010CMaPh.296..625S" } } }