{ "id": "math/0110176", "version": "v2", "published": "2001-10-17T15:17:21.000Z", "updated": "2003-05-22T17:22:15.000Z", "title": "On uniqueness of JSJ decompositions of finitely generated groups", "authors": [ "Max Forester" ], "comment": "11 pages; shortened and reorganized; mathematical content unchanged", "journal": "Comment. Math. Helv. 78 (2003) 740-751", "doi": "10.1007/s00014-003-0780-y", "categories": [ "math.GR", "math.GT" ], "abstract": "We give an example of two JSJ decompositions of a group that are not related by conjugation, conjugation of edge-inclusions, and slide moves. This answers the question of Rips and Sela stated in \"Cyclic splittings of finitely presented groups and the canonical JSJ decomposition,\" Ann. of Math. 146 (1997), 53-109. On the other hand we observe that any two JSJ decompositions of a group are related by an elementary deformation, and that strongly slide-free JSJ decompositions are genuinely unique. These results hold for the decompositions of Rips and Sela, Dunwoody and Sageev, and Fujiwara and Papasoglu, and also for accessible decompositions.", "revisions": [ { "version": "v2", "updated": "2003-05-22T17:22:15.000Z" } ], "analyses": { "subjects": [ "20F65", "20E08", "57M07" ], "keywords": [ "finitely generated groups", "uniqueness", "strongly slide-free jsj decompositions", "cyclic splittings", "canonical jsj decomposition" ], "tags": [ "journal article" ], "note": { "typesetting": "TeX", "pages": 11, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2001math.....10176F" } } }