{ "id": "1706.06937", "version": "v1", "published": "2017-06-21T14:43:14.000Z", "updated": "2017-06-21T14:43:14.000Z", "title": "Weak commutativity and finiteness properties of groups", "authors": [ "Martin R Bridson", "Dessislava H Kochloukova" ], "comment": "12 pages, 2 figures", "categories": [ "math.GR" ], "abstract": "We consider the group $\\mathfrak{X}(G)$ obtained from $G\\ast G$ by forcing each element $g$ in the first free factor to commute with the copy of $g$ in the second free factor. Deceptively complicated finitely presented groups arise from this construction: $\\mathfrak{X}(G)$ is finitely presented if and only if $G$ is finitely presented, but if $F$ is a non-abelian free group of finite rank then $\\mathfrak{X}(F)$ has a subgroup of finite index whose third homology is not finitely generated.", "revisions": [ { "version": "v1", "updated": "2017-06-21T14:43:14.000Z" } ], "analyses": { "subjects": [ "20F05", "20J05", "20E06" ], "keywords": [ "finiteness properties", "weak commutativity", "non-abelian free group", "second free factor", "first free factor" ], "note": { "typesetting": "TeX", "pages": 12, "language": "en", "license": "arXiv", "status": "editable" } } }