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The equivariant cohomology of hypertoric varieties and their real loci

Megumi Harada·Tara S. Holm
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Abstract

Let M be a Hamiltonian T space with a proper moment map, bounded below in some component. In this setting, we give a combinatorial description of the T-equivariant cohomology of M, extending results of Goresky, Kottwitz and MacPherson and techniques of Tolman and Weitsman. Moreover, when M is equipped with an antisymplectic involution σanticommuting with the action of T, we also extend to this noncompact setting the ``mod 2'' versions of these results to the real locus Q:= M^σof M. We give applications of these results to the theory of hypertoric varieties.

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Megumi Harada, Tara S. Holm. 2004-05-21. The equivariant cohomology of hypertoric varieties and their real loci. https://arxiv.org/abs/math/0405422

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