The T–equivariant Cohomology of Bott–samelson Varieties
نویسنده
چکیده
We consider the T–equivariant cohomology of Bott–Samelson desingularisations of Schubert varieties in the flag manifold of a connected semi–simple complex algebraic group of adjoint type with maximal torus T . We construct a combinatorially pure (in the sense of T. Braden and R. Macpherson) sheaf on the Bruhat graph of the associated Weyl group such that its global sections give the T–equivariant cohomology of our Bott–Samelson resolution.
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Vanishing theorem for the cohomology of line bundles on Bott-Samelson varieties
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