MS Seminar (Mathematics - String Theory)

Speaker: Georg Oberdieck (University of Bonn)
Title: Gopakumar-Vafa invariants for holomorphic-symplectic 4-folds
Date (JST): Thu, Feb 17, 2022, 17:00 - 18:30
Place: Zoom
Abstract: Gopakumar and Vafa defined invariants of Calabi-Yau 3-folds which underlie all Gromov-Witten invariants and are conjecturally (now proven) integers. Klemm and Pandharipande, and Pandharipande and Zinger defined similar invariants for Calabi-Yau 4 and 5-folds.

This talk, based on joint work with Yalong Cao and Yukinobu Toda, I will introduce parallel invariants for holomorphic-symplectic 4-folds (in primitive curve classes). A new phenomenon is the appearance of genus 2 curves. I will discuss computations of our invariants for various geometries, in particular for K3xK3 and the Hilbert square K3^[2].