Immersed spheres in symplectic 4-manifolds
We discuss conditions under which a symplectic 4-manifold has a compatible Kähler structure. The theory of \(J\)-holomorphic embedded spheres is extended to the immersed case. As a consequence, it is shown that a symplectic 4-manifold which has two different minimal reductions must be the blow-up of a rational or ruled surface.
scientific article; zbMATH DE number 118272
scientific article