Weakly Lefschetz symplectic manifolds.

Abstract

For a symplectic manifold, the harmonic cohomology of symplectic divisors (introduced by Donaldson, 1996) and of the more general symplectic zero loci (introduced by Auroux, 1997) are compared with that of its ambient space. We also study symplectic manifolds satisfying a weakly Lefschetz property, that is, the s–Lefschetz property. In particular, we consider the symplectic blow-ups CPm of the complex projective space CPm along weakly Lefschetz symplectic submanifolds M ⊂ CPm. As an application we construct, for each even integer s ≥ 2, compact symplectic manifolds which are s–Lefschetz but not (s + 1)–Lefschetz.