2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/77792Let $M$ be a symplectic manifold, equipped with a semifree symplectic circle action with a finite, nonempty fixed point set. We show that the circle action must be Hamiltonian, and $M$ must have the equivariant cohomology and Chern classes of $(P^1)^n$.Differential GeometrySymplectic Geometrytext