3 papers
math.SG2026
Symplectic torus actions with non-contractible orbits
Rei Henigman, Yael Karshon
We prove that a symplectic action on a closed connected -dimensional symplectic manifold is Hamiltonian if and only if its orbits are contractible. This generalizes a…
math.SG2024
Maximal symplectic torus actions
Rei Henigman
There are several different notions of maximal torus actions on smooth manifolds, in various contexts: symplectic, Riemannian, complex. In the symplectic context, for the so-called…
math.SG2024
Classification of symplectic non-Hamiltonian circle actions on 4-manifolds
Rei Henigman
We classify symplectic non-Hamiltonian circle actions on compact connected symplectic 4-manifolds, up to equivariant symplectomorphisms. Namely, we define a set of invariants, show…