{ "id": "0906.1601", "version": "v1", "published": "2009-06-08T21:12:20.000Z", "updated": "2009-06-08T21:12:20.000Z", "title": "Roots of Dehn twists", "authors": [ "Darryl McCullough", "Kashyap Rajeevsarathy" ], "comment": "15 pages, 6 figures", "categories": [ "math.GT" ], "abstract": "D. Margalit and S. Schleimer found examples of roots of the Dehn twist about a nonseparating curve in a closed orientable surface, that is, homeomorphisms whose nth power is isotopic to the Dehn twist. Our main theorem gives elementary number-theoretic conditions that describe the values of n for which an nth root exists, given the genus of the surface. Among its applications, we show that n must be odd, that the Margalit-Schleimer roots achieve the maximum value of n among the roots for a given genus, and that for a given odd n, nth roots exist for all genera greater than (n-2)(n-1)/2. We also describe all nth roots having n greater than or equal to the genus.", "revisions": [ { "version": "v1", "updated": "2009-06-08T21:12:20.000Z" } ], "analyses": { "subjects": [ "57M99" ], "keywords": [ "dehn twist", "nth root", "elementary number-theoretic conditions", "margalit-schleimer roots achieve", "main theorem" ], "note": { "typesetting": "TeX", "pages": 15, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2009arXiv0906.1601M" } } }