{ "id": "math/0702608", "version": "v1", "published": "2007-02-21T09:39:56.000Z", "updated": "2007-02-21T09:39:56.000Z", "title": "Pseudo-Anosov homeomorphisms and the lower central series of a surface group", "authors": [ "Justin Malestein" ], "comment": "23 pages, 8 figures; previous versions of this paper had the title: An algebraic criterion to detect pseudo-Anosovs", "journal": "Algebr. Geom. Topol. {\\bf 7} (2007), pp. 1921--1948", "categories": [ "math.GT" ], "abstract": "Let Gamma_k be the lower central series of a surface group Gamma of a compact surface S with one boundary component. A simple question to ponder is whether a mapping class of S can be determined to be pseudo-Anosov given only the data of its action on Gamma/Gamma_k for some k. In this paper, to each mapping class f which acts trivially on Gamma/Gamma_{k+1}, we associate an invariant Psi_k(f) in End(H_1(S, Z)) which is constructed from its action on Gamma/Gamma_{k+2} . We show that if the characteristic polynomial of Psi_k(f) is irreducible over Z, then f must be pseudo-Anosov. Some explicit mapping classes are then shown to be pseudo-Anosov.", "revisions": [ { "version": "v1", "updated": "2007-02-21T09:39:56.000Z" } ], "analyses": { "subjects": [ "57M60", "37E30" ], "keywords": [ "lower central series", "pseudo-anosov homeomorphisms", "surface group gamma", "boundary component", "compact surface" ], "tags": [ "journal article" ], "note": { "typesetting": "TeX", "pages": 23, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2007math......2608M" } } }