Lagrangian links quasimorphisms and non-simplicity of Hameomorphism group

Abstract: We will explain the construction of a sequence of homogeneous quasimorphisms of the area preserving homeomorphism group of the disc using Lagrangian Floer theory for links. This sequence of quasimorphisms has asymptotically vanishing defect, so it is asymptotically a homomorphism. We will then explain how studying the subleading asymptotic of these quasimorphisms enable us to show that the Hameomorphism group is not the smallest normal subgroup of the area preserving homeomorphism group. This is a joint work with Daniel Cristofaro-Gardiner, Vincent Humilière, Sobhan Seyfaddini and Ivan Smith.

Mathematics

Audience: researchers in the topic

Rutgers symplectic geometry seminar

Series comments: Please contact the organizers for zoom link Soham Chanda, Yuhan Sun, Chris Woodward