A Multiplicative Formula for Structure Constants in the Cohomology of Flag Varieties
نویسنده
چکیده
Let G be a complex semi-simple Lie group and let P, Q be a pair of parabolic subgroups of G such that Q contains P . Consider the flag varieties G/P , G/Q and Q/P . We show that certain structure constants in H∗(G/P ) with respect to the Schubert basis can be written as a product of structure constants coming from H∗(G/Q) and H∗(Q/P ) in a very natural way. The primary application is to compute Levi-movable structure constants defined by Belkale and Kumar in [2]. We also give a generalization of this product formula in the branching Schubert calculus setting.
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تاریخ انتشار 2008