{ "id": "math/0306306", "version": "v5", "published": "2003-06-20T09:54:21.000Z", "updated": "2004-11-29T22:16:32.000Z", "title": "Limit groups and groups acting freely on R^n-trees", "authors": [ "Vincent Guirardel" ], "comment": "Published by Geometry and Topology at http://www.maths.warwick.ac.uk/gt/GTVol8/paper39.abs.html", "journal": "Geometry and Toplogy 8 (2004) 1427--1470", "doi": "10.2140/gt.2004.8.1427", "categories": [ "math.GR", "math.GT", "math.LO" ], "abstract": "We give a simple proof of the finite presentation of Sela's limit groups by using free actions on R^n-trees. We first prove that Sela's limit groups do have a free action on an R^n-tree. We then prove that a finitely generated group having a free action on an R^n-tree can be obtained from free abelian groups and surface groups by a finite sequence of free products and amalgamations over cyclic groups. As a corollary, such a group is finitely presented, has a finite classifying space, its abelian subgroups are finitely generated and contains only finitely many conjugacy classes of non-cyclic maximal abelian subgroups.", "revisions": [ { "version": "v5", "updated": "2004-11-29T22:16:32.000Z" } ], "analyses": { "subjects": [ "20E08", "20E26" ], "keywords": [ "groups acting", "selas limit groups", "free action", "non-cyclic maximal abelian subgroups", "free abelian groups" ], "tags": [ "journal article" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable" } } }