# Olof Bergvall: Cohomology of moduli spaces of Del Pezzo surfaces

**Time: **
Wed 2019-02-20 11.00 - 12.00

**Lecturer: **
Olof Bergvall (Uppsala)

**Location: ** Room 306, House 6, Kräftriket, Department of Mathematics, Stockholm University ￼ ￼

Abstract:

A geometric marking of a Del Pezzo surface is a special type of basis for its Picard lattice. There is a Weyl group W acting on the moduli space M of geometrically marked Del Pezzo surfaces of degree d (by changing markings) and we would like to understand the cohomology groups of M as representations of W. We shall see how this can be achieved by comparing two fairly different descriptions of M and its relatives - point sets in the projective plane (over finite fields) and subspace arrangements (of hyperplanes and tori). Parts of the talk are joint work with Jonas Bergström and Frank Gounelas.