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arXiv math/98120061998-12-02math.DGmath.AGmath.ATmath.SG

On the cohomology rings of Hamiltonian T-spaces

Susan Tolman, Jonathan Weitsman

备注：: correction to references

英文摘要：

Let $M$ be a symplectic manifold equipped with a Hamiltonian action of a torus $T$. Let $F$ denote the fixed point set of the $T$-action and let $i:F\hookrightarrow M$ denote the inclusion. By a theorem of F. Kirwan \cite{K} the induced map $i^*:H_T^*(M) \to H_T^*(F)$ in equivariant cohomology is an injection. We give a simple proof of a formula of Goresky-Kottwitz-MacPherson \cite{GKM} for the image of the map $i^*$.

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