The hypertoric intersection cohomology ring

• 成果类型: Article
• 署名作者: Braden, Tom; Proudfoot, Nicholas
• 署名单位: University of Massachusetts System; University of Massachusetts Amherst; University of Oregon
• 刊物名称: INVENTIONES MATHEMATICAE
• ISSN/ISSBN: 0020-9910
• DOI: 10.1007/s00222-009-0181-y
• 发表日期: 2009
• 页码: 337-379
• 关键词: hard lefschetz theorem; koszul duality; localization

摘要

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.