Séminaire Algèbre Géométrie Algébrique Topologie Algébrique :
Le 04 décembre 2008 à 11:15 - salle 431
Présentée par Lange Herbert - Friedrich-Alexander-Universität Erlangen-Nürnberg
Clifford indices for vector bundles on curves
Clifford's theorem gives a bound for the dimension of the space of sections of a line bundle on a smooth projective curve. this bound is sharp only for hyperelliptic curves. For other curves, Clifford indices are introduced in order to give a better bound. In the talk two definitions of Clifford indices for vector bundles on a smooth projective curve of genus greater or equal to two are proposed. Moreover their values and relation to the usual Clifford index are discussed. This is joint work with Peter Newstead.