{ "id": "math/0301104", "version": "v2", "published": "2003-01-10T17:32:41.000Z", "updated": "2003-06-17T10:31:44.000Z", "title": "Freely braided elements in Coxeter groups", "authors": [ "R. M. Green", "J. Losonczy" ], "comment": "18 pages, AMSTeX. Results renumbered to agree with published version", "journal": "Annals of Combinatorics 6 (2002), 337-348", "categories": [ "math.CO", "math.GR" ], "abstract": "We introduce a notion of \"freely braided element\" for simply laced Coxeter groups. We show that an arbitrary group element $w$ has at most $2^{N(w)}$ commutation classes of reduced expressions, where $N(w)$ is a certain statistic defined in terms of the positive roots made negative by $w$. This bound is achieved if $w$ is freely braided. In the type $A$ setting, we show that the bound is achieved only for freely braided $w$.", "revisions": [ { "version": "v2", "updated": "2003-06-17T10:31:44.000Z" } ], "analyses": { "subjects": [ "20F55" ], "keywords": [ "freely braided element", "arbitrary group element", "simply laced coxeter groups", "commutation classes", "reduced expressions" ], "tags": [ "journal article" ], "note": { "typesetting": "AMS-TeX", "pages": 18, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2003math......1104G" } } }