{ "id": "2101.03060", "version": "v1", "published": "2021-01-08T15:26:39.000Z", "updated": "2021-01-08T15:26:39.000Z", "title": "Convex cores for actions on finite-rank median algebras", "authors": [ "Elia Fioravanti" ], "comment": "28 pages, no figures", "categories": [ "math.GT", "math.GR" ], "abstract": "We show that every action of a finitely generated group on a finite-rank median algebra admits a nonempty \"convex core\", even when no metric or topology is given. We then use this to deduce an analogue of the flat torus theorem for actions on connected finite-rank median spaces. We also prove that isometries of connected finite-rank median spaces are either elliptic or loxodromic.", "revisions": [ { "version": "v1", "updated": "2021-01-08T15:26:39.000Z" } ], "analyses": { "keywords": [ "convex core", "connected finite-rank median spaces", "finite-rank median algebra admits", "flat torus theorem", "finitely generated group" ], "note": { "typesetting": "TeX", "pages": 28, "language": "en", "license": "arXiv", "status": "editable" } } }