{ "id": "0711.0990", "version": "v2", "published": "2007-11-07T01:31:40.000Z", "updated": "2008-12-12T07:07:27.000Z", "title": "A combinatorial formula for Earle's twisted 1-cocycle on the mapping class group \\mathcal{M}_{g,*}", "authors": [ "Yusuke Kuno" ], "comment": "10 pages; corrected typos", "journal": "Mathematical Proceedings of the Cambridge Philosophical Society, 146, issue 01, pp. 109-118, 2009", "doi": "10.1017/S0305004108001680", "categories": [ "math.GT", "math.CV" ], "abstract": "We present a formula expressing Earle's twisted 1-cocycle on the mapping class group of a closed oriented surface of genus >=2 relative to a fixed base point, with coefficients in the first homology group of the surface. For this purpose we compare it with Morita's twisted 1-cocycle which is combinatorial. The key is the computation of these cocycles on a particular element of the mapping class group, which is topologically a hyperelliptic involution.", "revisions": [ { "version": "v2", "updated": "2008-12-12T07:07:27.000Z" } ], "analyses": { "subjects": [ "57N05", "32G15" ], "keywords": [ "mapping class group", "combinatorial formula", "first homology group", "formula expressing earles" ], "tags": [ "journal article" ], "note": { "typesetting": "TeX", "pages": 10, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2007arXiv0711.0990K" } } }