Symplectix 26 juin 2020

 Séance en visioconférence ( lien sur demande à symplectix@gmail.com ) à 13h45

Lien: http://bigbluebutton3.imj-prg.fr/b/cla-jeh-jn7

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