Construction of symplectic structures on 4-manifolds with a free circle action
نویسنده
چکیده
Let M be a closed 4-manifold with a free circle action. If the orbit manifold N3 satisfies an appropriate fibering condition, then we show how to represent a cone in H2(M ;R) by symplectic forms. This generalizes earlier constructions by Thurston, Bouyakoub and Fernández et al . In the case that M is the product 4-manifold S1 ×N , our construction complements our previous results and allows us to determine completely the symplectic cone of such 4-manifolds.
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