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Related papers: Schubert defects in Lagrangian Grassmannians

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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

We give an explicit formula for the degree of the Grothendieck polynomial of a Grassmannian permutation and a closely related formula for the Castelnuovo-Mumford regularity of the Schubert determinantal ideal of a Grassmannian permutation.…

Combinatorics · Mathematics 2020-07-30 Jenna Rajchgot , Yi Ren , Colleen Robichaux , Avery St. Dizier , Anna Weigandt

The Drinfel'd Lagrangian Grassmannian compactifies the space of algebraic maps of fixed degree from the projective line into the Lagrangian Grassmannian. It has a natural projective embedding arising from the canonical embedding of the…

Algebraic Geometry · Mathematics 2008-06-05 James Ruffo

We study the three point genus zero Gromov-Witten invariants on the Grassmannians which parametrize non-maximal isotropic subspaces in a vector space equipped with a nondegenerate symmetric or skew-symmetric form. We establish Pieri rules…

Algebraic Geometry · Mathematics 2015-05-13 Anders S. Buch , Andrew Kresch , Harry Tamvakis

We consider the Grassmannian X of (n-k)-dimensional subspaces of an n-dimensional complex vector space. We describe a `mirror dual' Landau-Ginzburg model for X consisting of the complement of a particular anti-canonical divisor in a…

Algebraic Geometry · Mathematics 2020-12-21 Bethany Marsh , Konstanze Rietsch

We describe recent work on positive descriptions of the structure constants of the cohomology of homogeneous spaces such as the Grassmannian, by degenerations and related methods. We give various extensions of these rules, some new and…

Algebraic Geometry · Mathematics 2007-05-23 Izzet Coskun , Ravi Vakil

We classify Schubert problems in the Grassmannian of 4-planes in 9-dimensional space by their Galois groups. Of the 31,806 essential Schubert problems in this Grassmannian, there are only 149 whose Galois group does not contain the…

Algebraic Geometry · Mathematics 2022-12-06 Abraham Martin del Campo , Frank Sottile , Robert Williams

We investigate cosmological perturbations of f(G) gravity in the presence of a scalar field. Using the 1 + 3 covariant formalism, we present the energy overdensity perturbation equations responsible for large scale structure formation.…

General Relativity and Quantum Cosmology · Physics 2023-12-27 Albert Munyeshyaka , Joseph Ntahompagaze , Tom Mutabazi , Manasse. R Mbonye

Let X be the direct product of two Grassmann varieties of k- and l-planes in a finite-dimensional vector space V, and let B be the isotropy group of a complete flag in V. We consider B-orbits in X, which are an analog to Schubert cells in…

Algebraic Geometry · Mathematics 2009-07-03 Evgeny Smirnov

In this paper we discuss physical derivations of the quantum K theory rings of symplectic Grassmannians. We compare to standard presentations in terms of Schubert cycles, but most of our work revolves around a proposed description in terms…

High Energy Physics - Theory · Physics 2023-08-30 W. Gu , L. Mihalcea , E. Sharpe , H. Zou

Let X be a symplectic or odd orthogonal Grassmannian parametrizing isotropic subspaces in a vector space equipped with a nondegenerate (skew) symmetric form. We prove a Giambelli formula which expresses an arbitrary Schubert class in…

Algebraic Geometry · Mathematics 2010-08-05 Anders S. Buch , Andrew Kresch , Harry Tamvakis

We obtain a combinatorial expression for the coefficients of the boundary map of real isotropic and odd orthogonal Grassmannians providing a natural generalization of the formulas already obtained for Lagrangian and maximal isotropic…

Algebraic Topology · Mathematics 2023-03-10 Jordan Lambert , Lonardo Rabelo

We describe a Schubert induction theorem, a tool for analyzing intersections on a Grassmannian over an arbitrary base ring. The key ingredient in the proof is the Geometric Littlewood-Richardson rule, described in a companion paper.…

Algebraic Geometry · Mathematics 2007-05-23 Ravi Vakil

Let $Q$ be a quiver of extended Dynkin type $D$. In this first of two papers, we show that the quiver Grassmannian $Gr_e(M)$ has a decomposition into affine spaces for every dimension vector $e$ and every indecomposable representation $M$…

Representation Theory · Mathematics 2015-07-03 Oliver Lorscheid , Thorsten Weist

The {\em Schubert derivation} is a distinguished Hasse-Schmidt derivation on the exterior algebra of a free abelian group, encoding the formalism of Schubert calculus for all Grassmannians at once. The purpose of this paper is to extend the…

Algebraic Geometry · Mathematics 2019-02-14 Letterio Gatto , Parham Salehyan

We study subsets of Grassmann varieties G(l,m) over a field F, such that these subsets are unions of Schubert cycles, with respect to a fixed flag. We study the linear spans of, and in case of positive characteristic, the number of points…

Algebraic Geometry · Mathematics 2007-05-23 Johan P. Hansen , Trygve Johnsen , Kristian Ranestad

We construct a family of moduli spaces, called generalized Lagrangian flag schemes, that are reducible Gorenstein (hence singular), and that admit well-behaved pushforward and pullback operations in Hermitian $K$-theory. These schemes arise…

Algebraic Geometry · Mathematics 2025-08-12 Tao Huang , Heng Xie

We study the equivariant cohomology of spherical perverse sheaves on the affine Grassmannian of a connected reductive group $G$ with support in the affine Grassmannian of any Levi subgroup $L$ of $G$. In doing so, we extend the work of…

Representation Theory · Mathematics 2023-09-19 Mark Macerato

Given a Schubert class on $Gr(k,V)$ where $V$ is a symplectic vector space of dimension $2n$, we consider its restriction to the symplectic Grassmannian $SpGr(k,V)$ of isotropic subspaces. Pragacz gave tableau formulae for positively…

Representation Theory · Mathematics 2019-04-16 Iva Halacheva , Allen Knutson , Paul Zinn-Justin

We outline a proof of a geometric version of the Satake isomorphism. Given a connected, complex algebraic reductive group G we show that the tensor category of representations of the dual group $\check G$ is naturally equivalent to a…

alg-geom · Mathematics 2008-02-03 Ivan Mirković , Kari Vilonen