Gleb Smirnov (ETHZ)
Title: Flops and non-Hamiltonian loops of diffeomorphisms
Abstract: In this talk, we will look at the topological structure of the identity component of the diffeomorphism group of algebraic surfaces. The main statement is simple: a simply-connected algebraic surface admits a loop of diffeomorphisms that is not homotopic to any loop of Hamiltonian diffeomorphisms. We will prove this statement under the mild assumption that our surface is a smoothing of a surface with a single double point singularity.
- A noter, le vendredi à 15h15 heure de Paris : Symplectic Zoominar (CRM-Montreal, Princeton/IAS, Tel Aviv, and Paris): https://dms.umontreal.ca/~cornea/Seminar.html