Talks and Seminars

SAG: Vafa-Witten invariants and framed sheavesSeminar Algebraic Geometry (SAG)

by Noah Arbesfeld (Utrecht)

→ Europe/Berlin
MPIM, Vivatsgasse, 7 - Lecture Hall (Max Planck Institute for Mathematics)

MPIM, Vivatsgasse, 7 - Lecture Hall

Max Planck Institute for Mathematics

120
Description

Tanaka-Thomas?s algebro-geometric approach to Vafa-Witten theory defines invariants of projective surfaces using moduli spaces of stable Higgs pairs. I will present work with M. Kool and T. Laarakker, in which we express certain Vafa-Witten invariants in terms of the equivariant geometry of a quiver variety, the moduli space of torsion-free framed sheaves on P^2. I'll then present wall-crossing results for this moduli space of framed sheaves and extract consequences for Vafa-Witten invariants, including a formula for so-called "vertical" Vafa-Witten invariants in rank 2.