{ "id": "2308.15376", "version": "v1", "published": "2023-08-29T15:14:48.000Z", "updated": "2023-08-29T15:14:48.000Z", "title": "Isoperimetry in Finitely Generated Groups", "authors": [ "Bruno Luiz Santos Correia", "Marc Troyanov" ], "comment": "20 pages. The results in this paper refine those in arXiv:2110.15798", "categories": [ "math.GR" ], "abstract": "We revisit the isoperimetric inequalities for finitely generated groups introduced and studied by N. Varopoulos, T. Coulhon and L. Saloff-Coste. Namely we show that a lower bound on the isoperimetric quotient of finite subsets in a finitely generated group is given by the $\\U-$transform of its growth function, which is a variant of the Legendre transform. From this lower bound, we obtain some asymptotic estimates for the F{\\o}lner function of the group. The paper also includes a discussion of some basic definitions from Geometric Group Theory and some basic properties of the $\\U$-transform, including some computational techniques and its relation with the Legendre transform.", "revisions": [ { "version": "v1", "updated": "2023-08-29T15:14:48.000Z" } ], "analyses": { "subjects": [ "20F65", "20F69", "05C63" ], "keywords": [ "finitely generated group", "isoperimetry", "lower bound", "legendre transform", "geometric group theory" ], "note": { "typesetting": "TeX", "pages": 20, "language": "en", "license": "arXiv", "status": "editable" } } }