{ "id": "1605.01192", "version": "v1", "published": "2016-05-04T09:30:02.000Z", "updated": "2016-05-04T09:30:02.000Z", "title": "Admitting a coarse embedding is not preserved under group extensions", "authors": [ "Goulnara Arzhantseva", "Romain Tessera" ], "comment": "15 pages", "categories": [ "math.GR", "math.FA", "math.MG" ], "abstract": "We construct a finitely generated group which is an extension of two groups coarsely embeddable into Hilbert space but which itself does not coarsely embed into Hilbert space. Our construction also provides a new infinite monster group: the first example of a finitely generated group that does not coarsely embed into Hilbert space and yet does not contain a weakly embedded expander.", "revisions": [ { "version": "v1", "updated": "2016-05-04T09:30:02.000Z" } ], "analyses": { "subjects": [ "46B85", "20F69", "22D10", "20E22" ], "keywords": [ "group extensions", "coarse embedding", "hilbert space", "finitely generated group", "infinite monster group" ], "note": { "typesetting": "TeX", "pages": 15, "language": "en", "license": "arXiv", "status": "editable" } } }