Speaker: Pranav Chakravarthy
Date: March 05, 2026
Affiliation: Université libre de Bruxelles

Abstract: In this talk, we present results on the homotopy type of the group of equivariant symplectomorphisms of $S^2 \times S^2$ and $\mathbb{C}P^2$ blown up once under the presence of a Hamiltonian circle and finite cyclic group actions. We show how questions about the homotopy type are related to questions about extensions of group actions. Our results rely on J-holomorphic techniques, Delzant's classification of toric actions, Karshon's classification of Hamiltonian circle actions on 4-manifolds. Time permitting, we shall discuss upcoming work on homotopy type of equivariant embedding spaces and their relation to symplectomorphism groups.