{ "id": "0906.2254", "version": "v2", "published": "2009-06-12T04:14:38.000Z", "updated": "2010-01-21T08:11:05.000Z", "title": "On intersections of conjugacy classes and Bruhat cells", "authors": [ "Kei Yuen Chan", "Jiang-Hua Lu", "Simon Kai Ming To" ], "comment": "20 pages. Revised version. to appear in Transformation Groups", "categories": [ "math.RT" ], "abstract": "For a connected complex semi-simple Lie group $G$ and a fixed pair $(B, B^-)$ of opposite Borel subgroups of $G$, we determine when the intersection of a conjugacy class $C$ in $G$ and a double coset $BwB^-$ is non-empty, where $w$ is in the Weyl group $W$ of $G$. The question comes from Poisson geometry, and our answer is in terms of the Bruhat order on $W$ and an involution $\\mc \\in W$ associated to $C$. We study properties of the elements $\\mc$. For $G = SL(n+1, \\Cset)$, we describe $\\mc$ explicitly for every conjugacy class $C$, and for the case when $w \\in W$ is an involution, we also give an explicit answer to when $C \\cap (BwB)$ is non-empty.", "revisions": [ { "version": "v2", "updated": "2010-01-21T08:11:05.000Z" } ], "analyses": { "keywords": [ "conjugacy classes", "bruhat cells", "intersection", "connected complex semi-simple lie group", "opposite borel subgroups" ], "note": { "typesetting": "TeX", "pages": 20, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2009arXiv0906.2254Y" } } }