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From moment graphs to intersection cohomology

Tom Braden·Robert MacPherson
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Abstract

We describe a method of computing equivariant and ordinary intersection cohomology of certain varieties with actions of algebraic tori, in terms of structure of the zero- and one-dimensional orbits. The class of varieties to which our formula applies includes Schubert varieties in flag varieties and affine flag varieties. We also prove a monotonicity result on local intersection cohomology stalks.

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Tom Braden, Robert MacPherson. 2001-01-09. From moment graphs to intersection cohomology. https://arxiv.org/abs/math/0008200

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