Mixed Hodge structures in log symplectic geometry

2020/05/22 by Andrew Harder, Harder, Andrew
Mathematics · #Advanced Algebra and Geometry #Algebraic Geometry (math.AG) #Algebraic Geometry and Number Theory #FOS: Mathematics #Geometry and complex manifolds

paper · pdf · doi:10.48550/arxiv.2005.11367

openalex publication_date 2020/05/22 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28

Abstract

We study the cohomology rings of snc log symplectic pairs (X,Y) which have log symplectic forms of pure weight. We show that under a certain natural condition, the cohomology ring of X ∖ Y exhibits the curious hard Lefschetz property. Analogous results are shown to hold for limit mixed Hodge structures associated to good degenerations of projective irreducible holomorphic symplectic manifolds. We provide several examples of log symplectic pairs of pure weight including a class of cluster-type varieties, and examples coming from the work of Feigin and Odesski. We show that the components of the central fiber of good degenerations of projective irreducible holomorphic symplectic manifolds produce log symplectic pairs.

Citations

• Cell decompositions of character varieties

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