{ "id": "1204.4418", "version": "v1", "published": "2012-04-19T17:37:43.000Z", "updated": "2012-04-19T17:37:43.000Z", "title": "The Picard group of a coarse moduli space of vector bundles in positive characteristic", "authors": [ "Norbert Hoffmann" ], "comment": "8 pages. to appear in: Central European Journal of Mathematics", "categories": [ "math.AG" ], "abstract": "Let C be a smooth projective curve over an algebraically closed field of arbitrary characteristic. Let M_{r,L}^{ss} denote the projective coarse moduli scheme of semistable rank r vector bundles over C with fixed determinant L. We prove Pic(M_{r,L}^{ss}) = Z, identify the ample generator, and deduce that M_{r,L}^{ss} is locally factorial. In characteristic zero, this has already been proved by Dr\\'{e}zet and Narasimhan. The main point of the present note is to circumvent the usual problems with Geometric Invariant Theory in positive caracteristic.", "revisions": [ { "version": "v1", "updated": "2012-04-19T17:37:43.000Z" } ], "analyses": { "subjects": [ "14D20", "14H60" ], "keywords": [ "coarse moduli space", "vector bundles", "picard group", "positive characteristic", "projective coarse moduli scheme" ], "note": { "typesetting": "TeX", "pages": 8, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2012arXiv1204.4418H" } } }