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Inventiones mathematicae

, Volume 177, Issue 2, pp 337–379 | Cite as

The hypertoric intersection cohomology ring

  • Tom BradenEmail author
  • Nicholas Proudfoot
Article

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.

Keywords

Toric Variety Localization Functor Equivariant Cohomology Schubert Variety Hyperplane Arrangement 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Springer-Verlag 2009

Authors and Affiliations

  1. 1.Department of Mathematics and StatisticsUniversity of MassachusettsAmherstUSA
  2. 2.Department of MathematicsUniversity of OregonEugeneUSA

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