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Related papers: Generic torus orbit closures in Schubert varieties

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We prove that if $\sigma \in S_m$ is a pattern of $w \in S_n$, then we can express the Schubert polynomial $\mathfrak{S}_w$ as a monomial times $\mathfrak{S}_\sigma$ (in reindexed variables) plus a polynomial with nonnegative coefficients.…

Combinatorics · Mathematics 2020-11-17 Alex Fink , Karola Mészáros , Avery St. Dizier

Gelfand-Tsetlin polytopes are classical objects in algebraic combinatorics arising in the representation theory of $\mathfrak{gl}_n(\mathbb{C})$. The integer point transform of the Gelfand-Tsetlin polytope $\mathrm{GT}(\lambda)$ projects to…

Combinatorics · Mathematics 2019-03-28 Ricky Ini Liu , Karola Mészáros , Avery St. Dizier

Let G be a compact connected Lie group G and T its maximal torus. The coadjoint orbit O_lambda through lambda in Lie(T)^* is canonically a symplectic manifold. Therefore we can ask the question about its Gromov width. In many known cases…

Symplectic Geometry · Mathematics 2013-03-01 Milena Pabiniak

The ring K(G/B) is isomorphic to a quotient of a Laurent polynomial ring by an ideal generated by certain W-symmetric functions and has a basis given by classes O_w, where O_w is the class of the structure sheaf of the Schubert variety X_w.…

Representation Theory · Mathematics 2007-05-23 Harsh Pittie , Arun Ram

Let a compact torus $T=T^{n-1}$ act on an orientable smooth compact manifold $X=X^{2n}$ effectively, with nonempty finite set of fixed points, and suppose that stabilizers of all points are connected. If $H^{odd}(X)=0$ and the weights of…

Algebraic Topology · Mathematics 2026-02-10 Anton Ayzenberg , Mikiya Masuda

Let $G$ be a connected reductive algebraic group over an algebraically closed field ${\bf k}$ of characteristic not equal to 2, let $\B$ be the variety of all Borel subgroups of $G$, and let $K$ be a symmetric subgroup of $G$. Fixing a…

Representation Theory · Mathematics 2011-04-15 Sam Evens , Jiang-Hua Lu

We prove a positive combinatorial formula for the equivariant class of an orbit closure in the space of representations of an arbitrary quiver of type $A$. Our formula expresses this class as a sum of products of Schubert polynomials…

Algebraic Geometry · Mathematics 2007-05-23 A. S. Buch , R. Rimanyi

We present a new method to achieve an embedded desingularization of a toric variety. Let $W$ be a regular toric variety defined by a fan $\Sigma$ and $X\subset W$ be a toric embedding. We construct a finite sequence of combinatorial…

Algebraic Geometry · Mathematics 2011-10-21 Rocio Blanco , Santiago Encinas

The operational Chow cohomology classes of a complete toric variety are identified with certain functions, called Minkowski weights, on the corresponding fan. The natural product of Chow cohomology classes makes the Minkowski weights into a…

alg-geom · Mathematics 2008-02-03 William Fulton , Bernd Sturmfels

In the present notes we generalize the classical work of Demazure [Invariants sym\'etriques entiers des groupes de Weyl et torsion] to arbitrary oriented cohomology theories and formal group laws. Let G be a split semisemiple linear…

Algebraic Geometry · Mathematics 2013-02-27 Baptiste Calmès , Victor Petrov , Kirill Zainoulline

We compute the $GL_{r+1}$-equivariant Chow class of the $GL_{r+1}$-orbit closure of any point $(x_1, \ldots, x_n) \in (\mathbb{P}^r)^n$ in terms of the rank polytope of the matroid represented by $x_1, \ldots, x_n \in \mathbb{P}^r$. Using…

Algebraic Geometry · Mathematics 2019-12-13 Mitchell Lee , Anand Patel , Hunter Spink , Dennis Tseng

We analyse topological orbifold conformal field theories on the symmetric product of a complex surface M. By exploiting the mathematics literature we show that a canonical quotient of the operator ring has structure constants given by…

High Energy Physics - Theory · Physics 2020-12-02 Songyuan Li , Jan Troost

We study a family of polynomials whose values express degrees of Schubert varieties in the generalized complex flag manifold G/B. The polynomials are given by weighted sums over saturated chains in the Bruhat order. We derive several…

Combinatorics · Mathematics 2007-05-23 Alexander Postnikov , Richard P. Stanley

To a direct sum of holomorphic line bundles, we can associate two fibrations, whose fibers are, respectively, the corresponding full flag manifold and the corresponding projective space. Iterating these procedures gives, respectively, a…

Algebraic Topology · Mathematics 2021-05-11 Shintarô Kuroki , Eunjeong Lee , Jongbaek Song , Dong Youp Suh

In this paper, we study the all genus Gromov-Witten theory for any GKM orbifold $X$. We generalize the Givental formula which is studied in the smooth case in \cite{Giv2} \cite{Giv3} \cite{Giv4} to the orbifold case. Specifically, we…

Algebraic Geometry · Mathematics 2016-05-10 Zhengyu Zong

This article presents a formula for products of Schubert classes in the quantum cohomology ring of the Grassmannian. We introduce a generalization of Schur symmetric polynomials for shapes that are naturally embedded in a torus. Then we…

Combinatorics · Mathematics 2007-05-23 Alexander Postnikov

In this paper we prove that the counting polynomials of certain torus orbits in products of partial flag varieties coincides with the Kac polynomials of supernova quivers, which arise in the study of the moduli spaces of certain irregular…

Representation Theory · Mathematics 2013-09-04 Paul E. Gunnells , Emmanuel Letellier , Fernando Rodriguez Villegas

This article explores the relationship between Schubert varieties and equivariant embeddings, using the framework of homogeneous fiber bundles over flag varieties. We show that the homogenous fiber bundles obtained from…

Algebraic Geometry · Mathematics 2023-09-19 Mahir Bilen Can , Pinaki Saha

We give a criterion for a collection of polynomials to be a universal Gr\"{o}bner basis for an ideal in terms of the multidegree of the closure of the corresponding affine variety in $(\mathbb{P}^1)^N$. This criterion can be used to give…

Algebraic Geometry · Mathematics 2024-11-27 Daoji Huang , Matt Larson

Introduced by Kodama and Williams, Bruhat interval polytopes are generalized permutohedra closely connected to the study of torus orbit closures and total positivity in Schubert varieties. We show that the 1-skeleton posets of these…

Combinatorics · Mathematics 2023-07-26 Christian Gaetz