{ "id": "2001.02822", "version": "v1", "published": "2020-01-09T03:34:33.000Z", "updated": "2020-01-09T03:34:33.000Z", "title": "Twisted conjugacy in free products", "authors": [ "Daciberg Goncalves", "Parameswaran Sankaran", "Peter Wong" ], "comment": "7 pages", "categories": [ "math.GR" ], "abstract": "Let $\\phi:G\\to G$ be an automorphism of a group which is a free-product of finitely many groups each of which is freely indecomposable and contains a proper finite index subgroup. We show that $G$ has infinitely many $\\phi$-twisted conjugacy classes. As an application, we show that if $G$ is the fundamental group of three-manifold which is not irreducible, then $G$ has the $R_\\infty$-property, that is, there are infinitely many $\\phi$-twisted conjugacy classes in $G$ for every automorphism $\\phi$ of $G$.", "revisions": [ { "version": "v1", "updated": "2020-01-09T03:34:33.000Z" } ], "analyses": { "subjects": [ "20E45", "22E40", "20E36" ], "keywords": [ "free products", "twisted conjugacy classes", "proper finite index subgroup", "automorphism", "fundamental group" ], "note": { "typesetting": "TeX", "pages": 7, "language": "en", "license": "arXiv", "status": "editable" } } }