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Excited Young diagrams and equivariant Schubert calculus

Takeshi Ikeda·Hiroshi Naruse
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Abstract

We describe the torus-equivariant cohomology ring of isotropic Grassmannians by using a localization map to the torus fixed points. We present two types of formulas for equivariant Schubert classes of these homogeneous spaces. The first formula involves combinatorial objects which we call ``excited Young diagrams'' and the second one is written in terms of factorial Schur $Q$- or $P$-functions. As an application, we give a Giambelli-type formula for the equivariant Schubert classes. We also give combinatorial and Pfaffian formulas for the multiplicity of a singular point in a Schubert variety.

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Takeshi Ikeda, Hiroshi Naruse. 2007-03-21. Excited Young diagrams and equivariant Schubert calculus. https://arxiv.org/abs/math/0703637

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