{ "id": "math/9809154", "version": "v1", "published": "1998-09-28T01:31:17.000Z", "updated": "1998-09-28T01:31:17.000Z", "title": "On Complexity of the Word Problem in Braid Groups and Mapping Class Groups", "authors": [ "Hessam Hamidi-Tehrani" ], "comment": "29 pages, 12 figures. To appear in Topology and its applications", "categories": [ "math.GT" ], "abstract": "We prove that the word problem in the mapping class group of the once-punctured surface of genus g has complexity O(|w|^2 g for |w| > log(g) where |w| is the length of the word in a (standard) set of generators. The corresponding bound in the case of the closed surface is O(|w|^2 g^2). We also carry out the same methods for the braid groups, and show that this gives a bound which improves the best known bound in this case; namely, the complexity of the word problem in the n-braid group is O(|w|^2 n), for |w| > log n. We state a similar result for mapping class groups of surfaces with several punctures.", "revisions": [ { "version": "v1", "updated": "1998-09-28T01:31:17.000Z" } ], "analyses": { "subjects": [ "20F10", "68Q25", "57S05" ], "keywords": [ "mapping class group", "word problem", "braid groups", "complexity", "n-braid group" ], "note": { "typesetting": "TeX", "pages": 29, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "1998math......9154H" } } }