L-cohomology of hyperkähler quotients
نویسنده
چکیده
Jost and Zuo’s theorem (adapting an earlier idea of Gromov [7]) states that if the Kähler form ω on a complete Kähler manifold satisfies ω = dβ, where β is a one-form of linear growth, then the only L harmonic forms lie in the middle dimension. An application of the same argument shows further that if G is a connected Lie group of isometries on a complete Riemannian manifold generated by Killing vector fields of linear growth, then G acts trivially on the space of L harmonic forms.
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