Results 21 to 30 of about 41 (41)

Generic stabilizers for simple algebraic groups acting on orthogonal and symplectic Grassmannians

Forum of Mathematics, Sigma
We consider faithful actions of simple algebraic groups on self-dual irreducible modules and on the associated varieties of totally singular subspaces, under the assumption that the dimension of the group is at least as large as the dimension of the ...
Aluna Rizzoli
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EQUIVARIANT $K$ -THEORY OF GRASSMANNIANS

Forum of Mathematics, Pi, 2017
We address a unification of the Schubert calculus problems solved by Buch [A Littlewood–Richardson rule for the $K$ -theory of Grassmannians, Acta Math. 189 (
OLIVER PECHENIK, ALEXANDER YONG
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Δ–Springer varieties and Hall–Littlewood polynomials

Forum of Mathematics, Sigma
The $\Delta $ -Springer varieties are a generalization of Springer fibers introduced by Levinson, Woo and the author that have connections to the Delta Conjecture from algebraic combinatorics.
Sean T. Griffin
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K-Orbit closures and Hessenberg varieties

Forum of Mathematics, Sigma
This article explores the relationship between Hessenberg varieties associated with semisimple operators with two eigenvalues and orbit closures of a spherical subgroup of the general linear group.
Mahir Bilen Can, Martha Precup, John Shareshian, Özlem Uğurlu   +3 more
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Coordinate rings of regular nilpotent Hessenberg varieties in the open opposite schubert cell

Forum of Mathematics, Sigma
Dale Peterson has discovered a surprising result that the quantum cohomology ring of the flag variety $\operatorname {\mathrm {GL}}_n({\mathbb {C}})/B$ is isomorphic to the coordinate ring of the intersection of the Peterson variety ...
Tatsuya Horiguchi, Tomoaki Shirato
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Geometrization of the Satake transform for mod p Hecke algebras

Forum of Mathematics, Sigma
We geometrize the mod p Satake isomorphism of Herzig and Henniart–Vignéras using Witt vector affine flag varieties for reductive groups in mixed characteristic. We deduce this as a special case of a formula, stated in terms of the geometry of generalized
Robert Cass, Yujie Xu
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Combinatorial formulas for shifted dual stable Grothendieck polynomials

Forum of Mathematics, Sigma
The K-theoretic Schur P- and Q-functions $G\hspace {-0.2mm}P_\lambda $ and $G\hspace {-0.2mm}Q_\lambda $ may be concretely defined as weight-generating functions for semistandard shifted set-valued tableaux.
Joel Lewis, Eric Marberg
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An inverse Grassmannian Littlewood–Richardson rule and extensions

Forum of Mathematics, Sigma
Chow rings of flag varieties have bases of Schubert cycles $\sigma _u $ , indexed by permutations. A major problem of algebraic combinatorics is to give a positive combinatorial formula for the structure constants of this basis.
Oliver Pechenik, Anna Weigandt
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Quantum K theory of Grassmannians, Wilson line operators and Schur bundles

Forum of Mathematics, Sigma
We prove a ‘Whitney’ presentation, and a ‘Coulomb branch’ presentation, for the torus equivariant quantum K theory of the Grassmann manifold $\mathrm {Gr}(k;n)$ , inspired from physics, and stated in an earlier paper.
Wei Gu, Leonardo Mihalcea, Eric Sharpe, Hao Zou   +3 more
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Smooth locus of twisted affine Schubert varieties and twisted affine Demazure modules

Forum of Mathematics, Sigma
Let ${\mathscr {G}} $ be a special parahoric group scheme of twisted type over the ring of formal power series over $\mathbb {C}$ , excluding the absolutely special case of $A^{(2)}_{2\ell }$ .
Marc Besson, Jiuzu Hong
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