{ "id": "2008.11548", "version": "v1", "published": "2020-08-26T13:24:18.000Z", "updated": "2020-08-26T13:24:18.000Z", "title": "Thick isotopy property and the mapping class groups of Heegaard splittings", "authors": [ "Daiki Iguchi" ], "comment": "8 pages, 1 figure", "categories": [ "math.GT" ], "abstract": "Let $M$ be a closed orientable $3$-manifold and $S$ a Heegaard surface of $M$. The space of Heegaard surfaces $\\mathcal{H}(M,S)$ is defined to be the space of left cosets $\\mathrm{Diff}(M)/\\mathrm{Diff}(M,S)$. We prove that the fundamental group $\\pi_{1}(\\mathcal{H}(M,S))$ is finitely generated if and only if any element of $\\pi_{1}(\\mathcal{H}(M,S))$ can be represented by a \"thick\" isotopy. As an application, we prove that the mapping class group of a strongly irreducible Heegaard splitting of a closed hyperbolic $3$-manifold is finitely generated.", "revisions": [ { "version": "v1", "updated": "2020-08-26T13:24:18.000Z" } ], "analyses": { "subjects": [ "57M60", "57M50" ], "keywords": [ "mapping class group", "thick isotopy property", "heegaard splitting", "heegaard surface", "fundamental group" ], "note": { "typesetting": "TeX", "pages": 8, "language": "en", "license": "arXiv", "status": "editable" } } }