26/04/2021, 13:30 — 14:00 — Online
Grace Mwakyoma, LisMath, Instituto Superior Técnico, Universidade de Lisboa
Classification of Hamiltonian circle actions on compact symplectic orbifolds of dimension 4
In this talk I want to present my thesis work towards the classification of Hamiltonian circle actions on compact orbifolds of dimension 4, with isolated cyclic singularties.
I will start by explaining what orbifolds are and how circle actions are defined on them. Then I will explain how to associate a graph to any such space, and show that two 4 dimensional orbifolds with Hamiltonian circle actions are isomorphic, if and only if their graphs are isomorphic. I will then give a list of minimal models from which many orbifolds with a Hamiltonian circle action can be constructed.This work is inspired and based on the work of Yael Karshon, who classified Hamiltonian circle actions on compact manifolds of dimension four.