{ "id": "0901.1512", "version": "v2", "published": "2009-01-12T08:04:26.000Z", "updated": "2010-01-29T11:13:24.000Z", "title": "Isometries on extremely non-complex Banach spaces", "authors": [ "Piotr Koszmider", "Miguel Martin", "Javier Meri" ], "comment": "18 pages, revised version, to appear in J. Inst. Math. Jussieu", "categories": [ "math.FA", "math.OA" ], "abstract": "Given a separable Banach space $E$, we construct an extremely non-complex Banach space (i.e. a space satisfying that $\\|Id + T^2\\|=1+\\|T^2\\|$ for every bounded linear operator $T$ on it) whose dual contains $E^*$ as an $L$-summand. We also study surjective isometries on extremely non-complex Banach spaces and construct an example of a real Banach space whose group of surjective isometries reduces to $\\pm Id$, but the group of surjective isometries of its dual contains the group of isometries of a separable infinite-dimensional Hilbert space as a subgroup.", "revisions": [ { "version": "v2", "updated": "2010-01-29T11:13:24.000Z" } ], "analyses": { "subjects": [ "46B04", "46B10", "46B20", "46E15", "47A99" ], "keywords": [ "extremely non-complex banach space", "dual contains", "real banach space", "separable infinite-dimensional hilbert space", "study surjective isometries" ], "note": { "typesetting": "TeX", "pages": 18, "language": "en", "license": "arXiv", "status": "editable" } } }