{ "id": "math/0504304", "version": "v1", "published": "2005-04-14T18:48:27.000Z", "updated": "2005-04-14T18:48:27.000Z", "title": "Operator Holes and extensions of sectorial operators and dual pairs of contractions", "authors": [ "Mark Malamud" ], "categories": [ "math.FA", "math.SP" ], "abstract": "A description of the set of $m$-sectorial extensions of a dual pair $\\{A_1,A_2\\}$ of nonnegative operators is obtained. Some classes of nonaccretive extensions of the dual pair $\\{A_1,A_2\\}$ are described too. Both problems are reduced to similar problems for a dual pair $\\{T_1,T_2\\}$ of nondensely defined symmetric contractions $T_j=(I-A_j)(I+A_j)^{-1},\\ j\\in\\{1,2\\}$. In turn these problems are reduced to the investigation of the corresponding operator \"holes\". A complete description of the set of all proper and improper extensions of a nonnegative operator is obtained too.", "revisions": [ { "version": "v1", "updated": "2005-04-14T18:48:27.000Z" } ], "analyses": { "subjects": [ "47A57", "47B25" ], "keywords": [ "dual pair", "sectorial operators", "operator holes", "nonnegative operator", "sectorial extensions" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2005math......4304M" } } }