{ "id": "math/0009034", "version": "v1", "published": "2000-09-04T09:35:01.000Z", "updated": "2000-09-04T09:35:01.000Z", "title": "Boundedness and surjectivity in Banach spaces", "authors": [ "Olav Nygaard" ], "comment": "15 pages", "categories": [ "math.FA" ], "abstract": "We define the ($w^\\ast$-) boundedness property and the ($w^\\ast$-) surjectivity property for sets in normed spaces. We show that these properties are pairwise equivalent in complete normed spaces by characterizing them in terms of a category-like property called ($w^\\ast$-) thickness. We give examples of interesting sets having or not having these properties. In particular, we prove that the tensor product of two $w^\\ast$-thick sets in $\\Xastast$ and $\\Yast$ is a $w^\\ast$-thick subset in $L(X,Y)^\\ast$ and obtain as a concequense that the set $w^\\ast -exp\\:B_{K(l_2)^\\ast}$ is $w^\\ast$-thick.", "revisions": [ { "version": "v1", "updated": "2000-09-04T09:35:01.000Z" } ], "analyses": { "subjects": [ "46B20" ], "keywords": [ "banach spaces", "boundedness property", "complete normed spaces", "surjectivity property", "tensor product" ], "note": { "typesetting": "TeX", "pages": 15, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2000math......9034N" } } }