English
Related papers

Related papers: Equivariant cohomology, Schubert calculus, and edg…

200 papers

Knutson, Tao, and Woodward formulated a Littlewood-Richardson rule for the cohomology ring of Grassmannians in terms of puzzles. Vakil and Wheeler-Zinn-Justin have found additional triangular puzzle pieces that allow one to express…

Combinatorics · Mathematics 2020-01-08 Pavlo Pylyavskyy , Jed Yang

In this paper, we study the T_w-equivariant cohomology of the weighted Grassmannians wGr(d,n) introduced by Corti-Reid where T_w is the n-dimensional torus that naturally acts on wGr(d,n). We introduce the equivariant weighted Schubert…

Algebraic Topology · Mathematics 2013-10-30 Hiraku Abe , Tomoo Matsumura

An important combinatorial result in equivariant cohomology and $K$-theory Schubert calculus is represented by the formulas of Billey and Graham-Willems for the localization of Schubert classes at torus fixed points. These formulas work…

Algebraic Geometry · Mathematics 2017-11-01 Cristian Lenart , Kirill Zainoulline

We introduce balanced shifted tableaux, as an analogue of balanced tableaux of Edelman and Greene, from the perspective of root systems of type B and C. We show that they are equinumerous to standard Young tableaux of the corresponding…

Combinatorics · Mathematics 2022-03-24 Jiyang Gao , Shiliang Gao , Yibo Gao

We state a precise conjectural isomorphism between localizations of the equivariant quantum K-theory ring of a flag variety and the equivariant K-homology ring of the affine Grassmannian, in particular relating their Schubert bases and…

Algebraic Geometry · Mathematics 2017-05-10 Thomas Lam , Changzheng Li , Leonardo C. Mihalcea , Mark Shimozono

We show that interlacing triangular arrays, introduced by Aggarwal-Borodin-Wheeler to study certain probability measures, can be used to compute structure constants for multiplying Schubert classes in the $K$-theory of Grassmannians, in the…

Combinatorics · Mathematics 2025-05-06 Christian Gaetz , Yibo Gao

Let X be an orthogonal Grassmannian parametrizing isotropic subspaces in an even dimensional vector space equipped with a nondegenerate symmetric form. We prove a Giambelli formula which expresses an arbitrary Schubert class in the singular…

Algebraic Geometry · Mathematics 2012-04-02 Anders S. Buch , Andrew Kresch , Harry Tamvakis

We introduce a family of rings of symmetric functions depending on an infinite sequence of parameters. A distinguished basis of such a ring is comprised by analogues of the Schur functions. The corresponding structure coefficients are…

Algebraic Geometry · Mathematics 2009-06-03 A. I. Molev

Let $T$ be a torus acting on $\CC^n$ in such a way that, for all $1\leq k\leq n$, the induced action on the grassmannian $G(k,n)$ has only isolated fixed points. This paper proposes a natural, elementary, explicit description of the…

Algebraic Geometry · Mathematics 2007-05-23 Letterio Gatto , Taise Santiago

The goal of the paper is to introduce a version of Schubert calculus for each dihedral reflection group W. That is, to each "sufficiently rich'' spherical building Y of type W we associate a certain cohomology theory and verify that, first,…

Group Theory · Mathematics 2010-08-11 Arkady Berenstein , Michael Kapovich

The ring of symmetric functions occupies a central place in algebraic combinatorics, with a particularly notable role in Schubert calculus, where the standard cell decompositions of Grassmannians yield the celebrated family of Schur…

Algebraic Topology · Mathematics 2023-07-20 Oliver Pechenik , Matthew Satriano

We describe the torus-equivariant cohomology of weighted partial flag orbifolds ${\mathrm{w}}\Sigma$ of type $A$. We establish counterparts of several results known for the partial flag variety that collectively constitute what we refer to…

Algebraic Topology · Mathematics 2019-06-14 Haniya Azam , Shaheen Nazir , Muhammad Imran Qureshi

This text is an introduction to equivariant cohomology, a classical tool for topological transformation groups, and to equivariant intersection theory, a much more recent topic initiated by D. Edidin and W. Graham. It is based on lectures…

Algebraic Geometry · Mathematics 2007-05-23 Michel Brion

These are lecture notes from the IMPANGA 2010 Summer School. The lectures survey some of the main features of equivariant cohomology at an introductory level. The first part is an overview, including basic definitions and examples. In the…

Algebraic Geometry · Mathematics 2011-12-08 Dave Anderson

We study root-theoretic Young diagrams to investigate the existence of a Lie-type uniform and nonnegative combinatorial rule for Schubert calculus. We provide formulas for (co)adjoint varieties of classical Lie type. This is a simplest case…

Combinatorics · Mathematics 2016-08-04 Dominic Searles , Alexander Yong

This is a review/announcement of results concerning the connection between certain exactly solvable two-dimensional models of statistical mechanics, namely loop models, and the equivariant $K$-theory of the cotangent bundle of the…

Algebraic Geometry · Mathematics 2018-07-16 Paul Zinn-Justin

Based on Thomas and Yong's K-theoretic jeu de taquin algorithm, we prove a uniform Littlewood-Richardson rule for the K-theoretic Schubert structure constants of all minuscule homogeneous spaces. Our formula is new in all types. For the…

Algebraic Geometry · Mathematics 2013-06-25 Anders Skovsted Buch , Matthew J. Samuel

The saturation theorem of [Knutson-Tao '99] concerns the nonvanishing of Littlewood-Richardson coefficients. In combination with work of [Klyachko '98], it implies [Horn '62]'s conjecture about eigenvalues of sums of Hermitian matrices.…

Combinatorics · Mathematics 2013-12-02 David Anderson , Edward Richmond , Alexander Yong

We generalize our puzzle formula for ordinary Schubert calculus on Grassmannians, to a formula for the T-equivariant Schubert calculus. The structure constants to be calculated are polynomials in {y_{i+1} - y_i}; they were shown…

Algebraic Topology · Mathematics 2010-04-26 Allen Knutson , Terence Tao

We prove an explicit combinatorial formula for the structure constants of the Grothendieck ring of a Grassmann variety with respect to its basis of Schubert structure sheaves. We furthermore relate K-theory of Grassmannians to a bialgebra…

Algebraic Geometry · Mathematics 2007-05-23 Anders Skovsted Buch