{ "id": "1202.3088", "version": "v3", "published": "2012-02-14T17:03:29.000Z", "updated": "2014-04-07T05:55:55.000Z", "title": "On the minimal space problem and a new result on existence of basic sequences in quasi-Banach spaces", "authors": [ "Cleon S. Barroso" ], "comment": "A subtle mistake in the proof of main result makes obsolete the paper", "categories": [ "math.FA" ], "abstract": "We prove that if $X$ is a quasi-normed space which possesses an infinite countable dimensional subspace with a separating dual, then it admits a strictly weaker Hausdorff vector topology. Such a topology is constructed explicitly. As an immediate consequence, we obtain an improvement of a well-known result of Kalton-Shapiro and Drewnowski by showing that a quasi-Banach space contains a basic sequence if and only if it contains an infinite countable dimensional subspace whose dual is separating. We also use this result to highlight a new feature of the minimal quasi-Banach space constructed by Kalton. Namely, which all of its $\\aleph_0$-dimensional subspaces fail to have a separating family of continuous linear functionals.", "revisions": [ { "version": "v3", "updated": "2014-04-07T05:55:55.000Z" } ], "analyses": { "keywords": [ "quasi-banach space", "minimal space problem", "basic sequence", "infinite countable dimensional subspace", "strictly weaker hausdorff vector topology" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2012arXiv1202.3088B" } } }