{ "id": "2011.05792", "version": "v1", "published": "2020-11-11T14:10:31.000Z", "updated": "2020-11-11T14:10:31.000Z", "title": "Signature of surface bundles and bounded cohomology", "authors": [ "Ursula Hamenstädt" ], "comment": "26 pages", "categories": [ "math.GT" ], "abstract": "Extending a result of Morita, we show that all tautological classes of the moduli space of genus g curves are bounded. As an application, we obtain that for a surface bundle $E\\to B$ over a closed surface, the Eulder characteristic $\\chi(E)$ and the signature $\\sigma(E)$ are related by $\\vert 3 \\sigma(E)\\vert \\leq \\vert \\chi(E)\\vert$.", "revisions": [ { "version": "v1", "updated": "2020-11-11T14:10:31.000Z" } ], "analyses": { "subjects": [ "20J06", "55N10", "57M07" ], "keywords": [ "surface bundle", "bounded cohomology", "moduli space", "eulder characteristic" ], "note": { "typesetting": "TeX", "pages": 26, "language": "en", "license": "arXiv", "status": "editable" } } }