{ "id": "math/0603685", "version": "v2", "published": "2006-03-29T15:38:19.000Z", "updated": "2009-06-03T16:00:15.000Z", "title": "Orbital Varieties and Unipotent Representations", "authors": [ "Thomas Pietraho" ], "comment": "35 pages", "categories": [ "math.RT" ], "abstract": "Using the notion of a Lagrangian covering, W. Graham and D. Vogan proposed a method of constructing representations from the coadjoint orbits for a complex semisimple Lie group $G$. When the coadjoint orbit $\\calO$ is nilpotent, a representation of $G$ is attached to each orbital variety of $\\calO$ in this way. In the setting of classical groups, we show that whenever it is possible to carry out the Graham-Vogan construction for an orbital variety of a spherical $\\mathcal{O}$, its infinitesimal character lies in a set of characters attached to $\\mathcal{O}$ by W. M. McGovern. Furthermore, we show that it is possible to carry out the Graham-Vogan construction for a sufficient number of orbital varieties to account for all the infinitesimal characters in this set.", "revisions": [ { "version": "v2", "updated": "2009-06-03T16:00:15.000Z" } ], "analyses": { "subjects": [ "22E46" ], "keywords": [ "orbital variety", "unipotent representations", "coadjoint orbit", "graham-vogan construction", "complex semisimple lie group" ], "note": { "typesetting": "TeX", "pages": 35, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2006math......3685P" } } }