{ "id": "1603.06804", "version": "v1", "published": "2016-03-22T14:22:09.000Z", "updated": "2016-03-22T14:22:09.000Z", "title": "Subgroup graph methods for presentations of finitely generated groups and the connectivity of associated simplicial complexes", "authors": [ "Cora Welsch" ], "categories": [ "math.GR" ], "abstract": "In this article we generalize the theory of subgroup graphs of subgroups of free groups to finite index subgroups $H$ of finitely generated groups $G$. We study and prove various properties of $H$ in relation to its subgroup graph $\\Gamma(H)$. For a finitely generated group $G$ we consider the poset $P_{\\text{fi}}(G)$ of all right cosets of all proper finite index subgroups of $G$. We use the theory of subgroup graphs to prove that for many finitely generated infinite groups the order complex $\\Delta P_{\\text{fi}} (G)$ and the corresponding nerve complex are contractible.", "revisions": [ { "version": "v1", "updated": "2016-03-22T14:22:09.000Z" } ], "analyses": { "keywords": [ "finitely generated group", "subgroup graph methods", "associated simplicial complexes", "presentations", "connectivity" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable" } } }