{ "id": "1103.5318", "version": "v2", "published": "2011-03-28T10:19:32.000Z", "updated": "2011-03-29T13:04:44.000Z", "title": "A geometric form of the Hahn-Banach extension theorem for L0 linear functions and the Goldstine-Weston theorem in random normed modules", "authors": [ "Shien Zhao", "Guang Shi" ], "comment": "14 pages", "categories": [ "math.FA" ], "abstract": "In this paper, we present a geometric form of the Hahn-Banach extension theorem for $L^{0}-$linear functions and prove that the geometric form is equivalent to the analytic form of the Hahn-Banach extension theorem. Further, we use the geometric form to give a new proof of a known basic strict separation theorem in random locally convex modules. Finally, using the basic strict separation theorem we establish the Goldstine-Weston theorem in random normed modules under the two kinds of topologies----the $(\\epsilon,\\lambda)-$topology and the locally $L^{0}-$convex topology, and also provide a counterexample showing that the Goldstine-Weston theorem under the locally $L^{0}-$convex topology can only hold for random normed modules with the countable concatenation property.", "revisions": [ { "version": "v2", "updated": "2011-03-29T13:04:44.000Z" } ], "analyses": { "subjects": [ "46A22", "46A16", "46A16", "46H25", "46H05" ], "keywords": [ "hahn-banach extension theorem", "random normed modules", "geometric form", "goldstine-weston theorem", "l0 linear functions" ], "note": { "typesetting": "TeX", "pages": 14, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2011arXiv1103.5318Z" } } }