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On semifree symplectic circle actions with isolated fixed points

Susan Tolman·Jonathan Weitsman
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Abstract

Let $M$ 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 $(P^1)^n$.

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Susan Tolman, Jonathan Weitsman. 1998-12-02. On semifree symplectic circle actions with isolated fixed points. https://arxiv.org/abs/math/9812015

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