Laure Flapan : Extremal divisors on moduli spaces of K3 surfaces

Posted by Ben Bakker , part of the Algebraic Geometry Seminar.

At

March 17, 2025, 3 p.m.

In

636 SEO

Abstract

We study the cone of pseudoeffective divisors on moduli spaces of K3 surfaces. We give numerical criteria for when (the irreducible components of) a Noether-Lefschetz divisor on these moduli spaces is an extremal ray of the pseudoeffective cone and use this to exhibit many new extremal divisors. We also discuss the question of whether the pseudoeffective cone is generated by Noether-Lefschetz divisors.