Positivity of equivariant Schubert classes through moment map degeneration
نویسندگان
چکیده
منابع مشابه
Positivity of Equivariant Schubert Classes through Moment Map Degeneration
For a flag manifold M = G/B with the canonical torus action, the T−equivariant cohomology is generated by equivariant Schubert classes, with one class τu for every element u of the Weyl group W . These classes are determined by their restrictions to the fixed point set M ≃ W , and the restrictions are polynomials with nonnegative integer coefficients in the simple roots. The main result of this...
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We prove a positivity property for the cup product in the T -equivariant cohomology of the flag variety. This was conjectured by D. Peterson and has as a consequence a conjecture of S. Billey. The result for the flag variety follows from a more general result about algebraic varieties with an action of a solvable linear algebraic group such that the unipotent radical acts with finitely many orb...
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Let LGn denote the Lagrangian Grassmannian parametrizing maximal isotropic (Lagrangian) subspaces of a fixed symplectic vector space of dimension 2n. For each strict partition λ = (λ1, . . . , λk) with λ1 ≤ n there is a Schubert variety X(λ). Let T denote a maximal torus of the symplectic group acting on LGn. Consider the T -equivariant cohomology of LGn and the T -equivariant fundamental class...
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ژورنال
عنوان ژورنال: Journal of Symplectic Geometry
سال: 2010
ISSN: 1527-5256,1540-2347
DOI: 10.4310/jsg.2010.v8.n4.a2