{ "id": "math/0502054", "version": "v3", "published": "2005-02-02T17:00:05.000Z", "updated": "2005-02-17T14:59:49.000Z", "title": "Minimality, homogeneity and topological 0-1 laws for subspaces of a Banach space", "authors": [ "Valentin Ferenczi" ], "categories": [ "math.FA", "math.CO" ], "abstract": "If a Banach space is saturated with basic sequences whose linear span embeds into the linear span of any subsequence, then it contains a minimal subspace. It follows that any Banach space is either ergodic or contains a minimal subspace. For a Banach space $X$ with an (unconditional) basis, topological 0-1 law type dichotomies are stated for block-subspaces of $X$ as well as for subspaces of $X$ with a successive FDD on its basis. A uniformity principle for properties of block-sequences, results about block-homogeneity, and a possible method to construct a Banach space with an unconditional basis, which has a complemented subspace without an unconditional basis, are deduced.", "revisions": [ { "version": "v3", "updated": "2005-02-17T14:59:49.000Z" } ], "analyses": { "subjects": [ "46B03", "46B15" ], "keywords": [ "banach space", "minimality", "homogeneity", "unconditional basis", "minimal subspace" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2005math......2054F" } } }