{ "id": "1205.4119", "version": "v2", "published": "2012-05-18T09:19:07.000Z", "updated": "2012-05-22T09:48:30.000Z", "title": "Moduli of sheaves and the Chow group of K3 surfaces", "authors": [ "Kieran G. O'Grady" ], "comment": "Deleted a footnote and replaced it by a sentence in the main body of the paper", "categories": [ "math.AG" ], "abstract": "Let X be a projective complex K3 surface. Beauville and Voisin singled out a 0-cycle c_X on X of degree 1: it is represented by any point lying on a rational curve in X. Huybrechts proved that the second Chern class of a rigid simple vector-bundle on X is a multiple of the Beauville-Voisin class c_X if certain hypotheses hold and he conjectured that the additional hypotheses are unnecessary. We believe that the following generalization of Huybrechts' conjecture holds. Let M and N be moduli spaces of stable pure sheaves on X (with fixed cohomological Chern characters) and suppose that they have the same dimension: then the set whose elements are second Chern classes of sheaves parametrized by the closure of M (in the corresponding moduli spaces of semistable sheaves) is equal to the set whose elements are second Chern classes of sheaves parametrized by the closure of N after a translation by a suitable multiple of c_X (so that degrees match). We will prove that the above statement holds under some additional assumptions.", "revisions": [ { "version": "v2", "updated": "2012-05-22T09:48:30.000Z" } ], "analyses": { "subjects": [ "14C15" ], "keywords": [ "chow group", "second chern classes", "moduli spaces", "projective complex k3 surface", "rigid simple vector-bundle" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2012arXiv1205.4119O" } } }