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arXiv · 1610.08121

Kirwan surjectivity for quiver varieties

Kevin McGerty·Thomas Nevins
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Abstract

For algebraic varieties defined by hyperkahler or, more generally, algebraic symplectic reduction, it is a long-standing question whether the "hyperkahler Kirwan map" on cohomology is surjective. We resolve this question in the affirmative for Nakajima quiver varieties. We also establish similar results for other cohomology theories and for the derived category. Our proofs use only classical topological and geometric arguments.

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Kevin McGerty, Thomas Nevins. 2016-10-25. Kirwan surjectivity for quiver varieties. https://doi.org/10.1007/s00222-017-0765-x

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