ERC StG 307119 - mini-workshop at Pavia

26 November 2015, Aula Beltrami, Dipartimento di Matematica "F. Casorati", Pavia

Speakers: Cinzia Casagrande (Torino), Ruadhai Dervan (Cambridge), Stefan Schreieder (Bonn).


14:00 - 15:00 Cinzia Casagrande: "On the birational geometry of Fano 4-folds with large second Betti number"

We will review some results and open problems in the study of the geometry of (smooth, complex) Fano 4-folds, in particular in the case of large second Betti number.

15:10 - 16:10 Ruadhai Dervan: "K-stability of finite covers"

An important result of Chen-Donaldson-Sun and Tian relates the existence of Kaehler-Einstein metrics on Fano varieties to an algebro-geometric notion called K-stability. K-stability is however understood in very few cases. We show that certain finite covers of K-stable Fano varieties are K-stable.

16:15 - 16:45 coffee break (at "bar della nave" - follow the organisers!)

16:45 - 17:45 Stefan Schreieder: "Theta divisors with curve summands and the Schottky problem"

This talk is about the following converse of Riemann's theorem: let A be an indecomposable principally polarized abelian variety whose theta divisor can be written as a sum Theta=C+Y of a curve C and a codimension two subvariety Y. Then C is smooth and A is isomorphic to the Jacobian of C. As an easy consequence, we deduce that an irreducible theta divisor admits a dominant rational map from a product of curves if and only if the corresponding principally polarized abelian variety is the Jacobian of a curve.

Organisers: Giulio Codogni, Paola Frediani, Jacopo Stoppa.

Registered participants: Anna Barbieri, Alberto Canonaco, Elisabetta Colombo, Pietro Pirola, Paola Porru, Paolo Stellari, Tom Sutherland, Elisa Tenni, Sara Torelli, Bert Van Geemen.

Social dinner: Osteria alle Carceri, 8 pm.