{ "id": "1109.2802", "version": "v4", "published": "2011-09-13T14:41:03.000Z", "updated": "2012-09-28T07:07:38.000Z", "title": "Prime-to-p étale covers of algebraic groups", "authors": [ "Michel Brion", "Tamás Szamuely" ], "comment": "14 pages, final version, to appear at Bulletin of the London Mathematical Society", "categories": [ "math.AG" ], "abstract": "Let G be a connected algebraic group over an algebraically closed field of characteristic p (possibly 0), and X a variety on which G acts transitively with connected stabilizers. We show that any \\'etale Galois cover of X of degree prime to p is also homogeneous, and that the maximal prime-to-p quotient of the \\'etale fundamental group of X is commutative. We moreover obtain an explicit bound for the number of topological generators of the said quotient. When G is commutative, we also obtain a description of the prime-to-p torsion in the Brauer group of G.", "revisions": [ { "version": "v4", "updated": "2012-09-28T07:07:38.000Z" } ], "analyses": { "subjects": [ "14E20", "14F35", "14L10", "14M17" ], "keywords": [ "etale fundamental group", "maximal prime-to-p quotient", "etale galois cover", "connected algebraic group", "brauer group" ], "note": { "typesetting": "TeX", "pages": 14, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2011arXiv1109.2802B" } } }