{ "id": "math/0611454", "version": "v3", "published": "2006-11-15T10:18:48.000Z", "updated": "2006-12-05T17:08:58.000Z", "title": "A fast algorithm to the conjugacy problem on generic braids", "authors": [ "Ki Hyoung Ko", "Jang Won Lee" ], "comment": "12 pages, 1 figure. to appear in the Proceedings of the International Workshop on Knot Theory for Scientific Objects: OCAMI Studies Vol 1. Knot Theory for Scientific Objects", "categories": [ "math.GT", "math.GR" ], "abstract": "Random braids that are formed by multiplying randomly chosen permutation braids are studied by analyzing their behavior under Garside's weighted decomposition and cycling. Using this analysis, we propose a polynomial-time algorithm to the conjugacy problem that is successful for random braids in overwhelming probability. As either the braid index or the number of permutation-braid factors increases, the success probability converges to 1 and so, contrary to the common belief, the distribution of hard instances for the conjugacy problem is getting sparser. We also prove a conjecture by Birman and Gonz\\'{a}lez-Meneses that any pseudo-Anosov braid can be made to have a special weighted decomposition after taking power and cycling. Moreover we give polynomial upper bounds for the power and the number of iterated cyclings required.", "revisions": [ { "version": "v3", "updated": "2006-12-05T17:08:58.000Z" } ], "analyses": { "subjects": [ "20F36", "20F10" ], "keywords": [ "conjugacy problem", "generic braids", "fast algorithm", "random braids", "polynomial upper bounds" ], "note": { "typesetting": "TeX", "pages": 12, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2006math.....11454K" } } }