{ "id": "0706.3425", "version": "v2", "published": "2007-06-23T01:56:53.000Z", "updated": "2008-03-24T16:18:43.000Z", "title": "Twisted conjugacy classes in nilpotent groups", "authors": [ "Daciberg Gonçalves", "Peter Wong" ], "comment": "22 pages; section 6 has been moved to section 2 and minor modification has been made on exposition; to be published in Crelle J", "journal": "J. Reine Angew. Math. 633 (2009), 11--27", "categories": [ "math.GR", "math.AT" ], "abstract": "A group is said to have the $R_\\infty$ property if every automorphism has an infinite number of twisted conjugacy classes. We study the question whether $G$ has the $R_\\infty$ property when $G$ is a finitely generated torsion-free nilpotent group. As a consequence, we show that for every positive integer $n\\ge 5$, there is a compact nilmanifold of dimension $n$ on which every homeomorphism is isotopic to a fixed point free homeomorphism. As a by-product, we give a purely group theoretic proof that the free group on two generators has the $R_\\infty$ property. The $R_{\\infty}$ property for virtually abelian and for $\\mathcal C$-nilpotent groups are also discussed.", "revisions": [ { "version": "v2", "updated": "2008-03-24T16:18:43.000Z" } ], "analyses": { "subjects": [ "20E45", "55M20" ], "keywords": [ "twisted conjugacy classes", "purely group theoretic proof", "finitely generated torsion-free nilpotent group", "fixed point free homeomorphism", "compact nilmanifold" ], "tags": [ "journal article" ], "note": { "typesetting": "TeX", "pages": 22, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2007arXiv0706.3425G" } } }