{ "id": "math/0406477", "version": "v2", "published": "2004-06-23T15:56:39.000Z", "updated": "2004-12-07T15:38:13.000Z", "title": "Some equivalence relations which are Borel reducible to isomorphism between separable Banach spaces", "authors": [ "Valentin Ferenczi", "Eloi Medina Galego" ], "comment": "23 pages; 2 figures", "categories": [ "math.FA", "math.LO" ], "abstract": "We improve the known results about the complexity of the relation of isomorphism between separable Banach spaces up to Borel reducibility, and we achieve this using the classical spaces $c_0$, $\\ell_p$ and $L_p$, $1 \\leq p <2$. More precisely, we show that the relation $E_{K_{\\sigma}}$ is Borel reducible to isomorphism and complemented biembeddability between subspaces of $c_0$ or $\\ell_p, 1 \\leq p <2$. We show that the relation $E_{K_{\\sigma}} \\otimes =^+$ is Borel reducible to isomorphism, complemented biembeddability, and Lipschitz equivalence between subspaces of $L_p, 1 \\leq p <2$.", "revisions": [ { "version": "v2", "updated": "2004-12-07T15:38:13.000Z" } ], "analyses": { "subjects": [ "03E15", "46B03" ], "keywords": [ "separable banach spaces", "borel reducible", "equivalence relations", "isomorphism", "complemented biembeddability" ], "note": { "typesetting": "TeX", "pages": 23, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2004math......6477F" } } }