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arXiv · alg-geom/9501001

Cohomology of compact hyperkaehler manifolds

Abstract

Let M be a compact simply connected hyperkähler (or holomorphically symplectic) manifold, \dim H^2(M)=n. Assume that M is not a product of hyperkaehler manifolds. We prove that the Lie algebra so(n-3,3) acts by automorphisms on the cohomology ring H^*(M). Under this action, the space H^2(M) is isomorphic to the fundamental representation of so(n-3,3). Let A^r be the subring of H^*(M) generated by H^2(M). We construct an action of the Lie algebra so(n-2,4) on the space A, which preserves A^r. The space A^r is an irreducible representation of so(n-2,4). This makes it possible to compute the ring A^r explicitely.

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BibTeXRIS

Misha Verbitsky. 1995-05-13. Cohomology of compact hyperkaehler manifolds. https://arxiv.org/abs/alg-geom/9501001

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