# From Six to Four

## Location

383N

Event Series

Event Type

Seminar

Monday, February 5, 2024 4:00 PM

Amanda Hirschi (Sorbonne University)

I will discuss joint work with Luya Wang on the other direction of the Donaldson 4-6 problem. Specifically, we show that any two simply-connected symplectic 4-manifolds, whose products with S^2 are deformation equivalent, have the same Gromov-Witten invariants. The proof relies on a generalisation of the product formula of Hirschi-Swaminathan to include gravitational descendants, as well as using classical invariants to constrain the action of diffeomorphisms on cohomology.