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arXiv · 0802.0641

The hypertoric intersection cohomology ring

Tom Braden·Nicholas J. Proudfoot
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Abstract

We present a functorial computation of the equivariant intersection cohomology of a hypertoric variety, and endow it with a natural ring structure. When the hyperplane arrangement associated with the hypertoric variety is unimodular, we show that this ring structure is induced by a ring structure on the equivariant intersection cohomology sheaf in the equivariant derived category. The computation is given in terms of a localization functor which takes equivariant sheaves on a sufficiently nice stratified space to sheaves on a poset.

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Tom Braden, Nicholas J. Proudfoot. 2008-10-04. The hypertoric intersection cohomology ring. https://doi.org/10.1007/s00222-009-0181-y

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