Circle valued momentum maps for symplectic periodic flows
نویسندگان
چکیده
We give a detailed proof of the well-known classical fact that every symplectic circle action on a compact manifold admits a circle valued momentum map relative to some symplectic form. This momentum map is Morse-Bott-Novikov and each connected component of the fixed point set has even index. These proofs do not appear to be written elsewhere.
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