{ "id": "2001.02027", "version": "v1", "published": "2020-01-07T13:43:55.000Z", "updated": "2020-01-07T13:43:55.000Z", "title": "Twisted conjugacy and commensurability invariance", "authors": [ "Parameswaran Sankaran", "Peter Wong" ], "comment": "15 pages", "categories": [ "math.GR" ], "abstract": "A group $G$ is said to have property $R_{\\infty}$ if for every automorphism $\\varphi \\in {\\rm Aut}(G)$, the cardinality of the set of $\\varphi$-twisted conjugacy classes is infinite. Many classes of groups are known to have such property. However, very few examples are known for which $R_{\\infty}$ is {\\it geometric}, i.e., if $G$ has property $R_{\\infty}$ then any group quasi-isometric to $G$ also has property $R_{\\infty}$. In this paper, we give examples of groups and conditions under which $R_{\\infty}$ is preserved under commensurability. The main tool is to employ the Bieri-Neumann-Strebel invariants and other related invariants.", "revisions": [ { "version": "v1", "updated": "2020-01-07T13:43:55.000Z" } ], "analyses": { "subjects": [ "20F65", "20E45" ], "keywords": [ "commensurability invariance", "bieri-neumann-strebel invariants", "main tool", "twisted conjugacy classes", "group quasi-isometric" ], "note": { "typesetting": "TeX", "pages": 15, "language": "en", "license": "arXiv", "status": "editable" } } }