{ "id": "1011.5045", "version": "v1", "published": "2010-11-23T10:05:56.000Z", "updated": "2010-11-23T10:05:56.000Z", "title": "The closure of a sheet is not always a union of sheets", "authors": [ "Michael Bulois" ], "comment": "short note, 3 pages", "categories": [ "math.RT" ], "abstract": "In this note we answer to a frequently asked question. If G is an algebraic group acting on a variety V, a G-sheet of V is an irreducible component of V^(m), the set of elements of V whose G-orbit has dimension m. We focus on the case of the adjoint action of a semisimple group on its Lie algebra. We give two families of examples of sheets whose closure is not a union of sheets in this setting.", "revisions": [ { "version": "v1", "updated": "2010-11-23T10:05:56.000Z" } ], "analyses": { "subjects": [ "17B45", "20G05" ], "keywords": [ "lie algebra", "semisimple group", "adjoint action", "irreducible component", "algebraic group acting" ], "note": { "typesetting": "TeX", "pages": 3, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2010arXiv1011.5045B" } } }