Tue, March 24, 2026
10:20 am - 11:15 am
Math Tower (MW) 154
Laure Flapan
Michigan State University
Title
Cones of divisors on moduli spaces of K3 surfaces
Abstract
An important, yet notoriously difficult invariant for understanding the birational geometry of an algebraic variety X is its cone of pseudoeffective divisors. In this talk, we will focus on the case that X is a moduli space of polarized K3 surfaces or hyperkähler manifolds. In this case, such an X comes equipped with a special class of divisors, called Noether-Lefschetz divisors. We will describe numerical criteria for when a Noether-Lefschetz divisor is extremal on such an X and discuss the question of whether the psuedoeffective cone is generated by Noether-Lefschetz divisors. This is joint work with Ignacio Barros and Riccardo Zuffetti.