{ "id": "math/0609616", "version": "v2", "published": "2006-09-21T16:30:21.000Z", "updated": "2007-02-22T23:10:18.000Z", "title": "Conjugacy in Garside Groups III: Periodic braids", "authors": [ "Joan S. Birman", "Volker Gebhardt", "Juan Gonzalez-Meneses" ], "comment": "33 pages, 13 figures. Classical references implying Corollaries 12 and 15 have been added. To appear in Journal of Algebra", "categories": [ "math.GT", "math.GR" ], "abstract": "An element in Artin's braid group B_n is said to be periodic if some power of it lies in the center of B_n. In this paper we prove that all previously known algorithms for solving the conjugacy search problem in B_n are exponential in the braid index n for the special case of periodic braids. We overcome this difficulty by putting to work several known isomorphisms between Garside structures in the braid group B_n and other Garside groups. This allows us to obtain a polynomial solution to the original problem in the spirit of the previously known algorithms. This paper is the third in a series of papers by the same authors about the conjugacy problem in Garside groups. They have a unified goal: the development of a polynomial algorithm for the conjugacy decision and search problems in B_n, which generalizes to other Garside groups whenever possible. It is our hope that the methods introduced here will allow the generalization of the results in this paper to all Artin-Tits groups of spherical type.", "revisions": [ { "version": "v2", "updated": "2007-02-22T23:10:18.000Z" } ], "analyses": { "subjects": [ "20F36", "20F10" ], "keywords": [ "garside groups", "periodic braids", "conjugacy search problem", "artins braid group", "artin-tits groups" ], "note": { "typesetting": "TeX", "pages": 33, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2006math......9616B" } } }