{ "id": "1405.1979", "version": "v2", "published": "2014-05-08T15:44:21.000Z", "updated": "2015-02-06T11:17:17.000Z", "title": "On finite groups of isometries of handlebodies in arbitrary dimensions and finite extensions of Schottky groups", "authors": [ "Mattia Mecchia", "Bruno P. Zimmermann" ], "comment": "13 pages; this is the final version to appear in Fund. Math", "categories": [ "math.GT" ], "abstract": "It is known that the order of a finite group of diffeomorphisms of a 3-dimensional handlebody of genus g > 1 is bounded by the linear polynomial 12(g-1), and that the order of a finite group of diffeomorphisms of a 4-dimensional handlebody (or equivalently, of its boundary 3-manifold), faithful on the fundamental group, is bounded by a quadratic polynomial in g (but not by a linear one). In the present paper we prove a generalization for handlebodies of arbitrary dimension d, uniformizing handlebodies by Schottky groups and considering finite groups of isometries of such handlebodies. We prove that the order of a finite group of isometries of a handlebody of dimension d acting faithfully on the fundamental group is bounded by a polynomial of degree d/2 in g if d is even, and of degree (d+1)/2 if d is odd, and that the degree d/2 for even d is best possible. This implies then analogous polynomial Jordan-type bounds for arbitrary finite groups of isometries of handlebodies (since a handlebody of dimension d > 3 admits S^1-actions, there does not exist an upper bound for the order of the group itself ).", "revisions": [ { "version": "v1", "updated": "2014-05-08T15:44:21.000Z", "title": "On finite groups of isometries of handlebodies of dimension d \\ge 3 and finite extensions of Schottky groups", "comment": "12 pages", "journal": null, "doi": null, "authors": [ "Bruno P. Zimmermann" ] }, { "version": "v2", "updated": "2015-02-06T11:17:17.000Z" } ], "analyses": { "subjects": [ "57S17", "57S25", "57M60", "20H10" ], "keywords": [ "handlebody", "schottky groups", "finite extensions", "isometries", "fundamental group" ], "note": { "typesetting": "TeX", "pages": 13, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2014arXiv1405.1979M" } } }