Deformation theory and moduli spaces of abelian varieties in positive characteristic (Elena Mantovan, Berkeley) The theory of abelian varieties is a very classical topic in algebraic geometry which plays a fundamental role in number theory, and in particular in the Langlands program. Abelian varieties in positive characteristic exhibit interesting features not seen in characteristic zero. In my working group, we will study some of the extra structure present when studying abelian varieties mod p. Possible topics will include: - Honda-Tate theory (i.e. classification of abelian varieties over finite fields up to isogeny) - Serre-Tate theory (i.e. deformation theory of ordinary abelian varieties) - Newton polygons and stratifications of the moduli spaces of abelian varieties