Résume | ZOOM:870 3083 2332, demander le mot de passe à Olivier Benoist, Olivier Debarre ou Frederic Han, ou inscrivez vous sur la liste de diffusion
Abstract: We show that the degree of the Gauss map for subvarieties of
abelian varieties is semicontinuous in families, and we discuss its jump
loci. In the case of theta divisors this gives a finite stratification
of the moduli space of ppav's including the Torelli locus and the Prym
locus. More generally we obtain semicontinuity results for the
intersection cohomology of algebraic varieties with a finite morphism to
an abelian variety. This is joint work with Giulio Codogni; if time
permits, we will illustrate our techniques with some recent results
about Gauss maps on various Andreotti-Mayer loci. |