English
Related papers

Related papers: Positivity in Weighted Flag Varieties

200 papers

We extend the short presentation due to [Borel '53] of the cohomology ring of a generalized flag manifold to a relatively short presentation of the cohomology of any of its Schubert varieties. Our result is stated in a root-system uniform…

Combinatorics · Mathematics 2010-11-29 Victor Reiner , Alexander Woo , Alexander Yong

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

Let $\pi:X\to Y$ be a factor map, where $(X,\sigma_X)$ and $(Y,\sigma_Y)$ are subshifts over finite alphabets. Assume that $X$ satisfies weak specification. Let $\ba=(a_1,a_2)\in \R^2$ with $a_1>0$ and $a_2\geq 0$. Let $f$ be a continuous…

Dynamical Systems · Mathematics 2009-09-24 De-Jun Feng

In this article we introduce flag Bott manifolds of general Lie type as the total spaces of iterated flag bundles. They generalize the notion of flag Bott manifolds and generalized Bott manifolds, and admit nice torus actions. We calculate…

Algebraic Topology · Mathematics 2020-06-09 Shizuo Kaji , Shintarô Kuroki , Eunjeong Lee , Dong Youp Suh

The main result of this paper is the existence of Galois representations associated with the mod $p$ (or mod $p^m$) cohomology of the locally symmetric spaces for $\GL_n$ over a totally real or CM field, proving conjectures of Ash and…

Number Theory · Mathematics 2015-06-03 Peter Scholze

Toric orbifolds are a topological generalization of projective toric varieties associated to simplicial fans. We introduce some sufficient conditions on the combinatorial data associated to a toric orbifold to ensure the existence of an…

Algebraic Geometry · Mathematics 2021-06-29 Soumen Sarkar , V. Uma

The purpose of the paper is to give a sharp asymptotic description of the weights that appear in the syzygies of a toric variety. We prove that as the positivity of the embedding increases, in any strand of syzygies, torus weights after…

Algebraic Geometry · Mathematics 2015-01-28 Xin Zhou

Let $\mathfrak{g}$ be an untwisted affine Lie algebra with associated Weyl group $W_a$. To any level 0 weight $\gamma$ we associate a weighted graph $\Gamma_\gamma$ that encodes the orbit of $\gamma$ under the action $W_a$. We show that the…

Combinatorics · Mathematics 2023-06-29 Jérémie Guilhot , Cédric Lecouvey , Pierre Tarrago

We give the explicit formulas of the flag curvatures of left invariant Matsumoto and Kropina metrics of Berwald type. We can see these formulas are different from previous results given recently. Using these formulas, we prove that at any…

Differential Geometry · Mathematics 2024-07-23 Masoumeh Hosseini , Hamid Reza Salimi Moghaddam

We relate properties of weighted flags (or multiflags) of type AD to statistics of the corresponding Weyl groups. For type A, we recover the Mahonian statistics on symmetric groups. Finally, we sketch briefly an easy extension incorporating…

Combinatorics · Mathematics 2018-11-13 Roland Bacher

Let $\mathcal{H}$ be a noncommutative regular projective curve over a perfect field $k$. We study global and local properties of the Auslander-Reiten translation $\tau$ and give an explicit description of the complete local rings, with the…

Algebraic Geometry · Mathematics 2017-02-09 Dirk Kussin

We determine the structure of the equivariant cohomology and $K$-theory of Bott towers. By restriction, we obtain similar results for Bott-Samelson varieties. This results allow us to describe more precisely the equivariant cohomology and…

Algebraic Geometry · Mathematics 2007-05-23 Matthieu Willems

The paper computes the Witt-sheaf cohomology rings of partial flag varieties in type A in terms of the Pontryagin classes of the subquotient bundles. The proof is based on a Leray-Hirsch-type theorem for Witt-sheaf cohomology for the…

Algebraic Geometry · Mathematics 2024-11-18 Thomas Hudson , Ákos K. Matszangosz , Matthias Wendt

We show a Z^2-filtered algebraic structure and a "quantum to classical" principle on the torus-equivariant quantum cohomology of a complete flag variety of general Lie type, generalizing earlier works of Leung and the second author. We also…

Algebraic Geometry · Mathematics 2015-06-03 Yongdong Huang , Changzheng Li

Let G be a split semisimple linear algebraic group over a field k0. Let E be a G-torsor over a field extension k of k0. Let h be an algebraic oriented cohomology theory in the sense of Levine-Morel. Consider a twisted form E/B of the…

Algebraic Geometry · Mathematics 2016-06-27 Alexander Neshitov , Victor Petrov , Nikita Semenov , Kirill Zainoulline

We give a presentation for the (integral) torus-equivariant Chow ring of the quot scheme, a smooth compactification of the space of rational curves of degree d in the Grassmannian. For this presentation, we refine Evain's extension of the…

Algebraic Geometry · Mathematics 2010-03-29 Tom Braden , Linda Chen , Frank Sottile

We prove that the group of normalized cohomological invariants of degree 3 modulo the subgroup of semidecomposable invariants of a semisimple split linear algebraic group G is isomorphic to the torsion part of the Chow group of codimension…

Algebraic Geometry · Mathematics 2015-08-19 Alexander Merkurjev , Alexander Neshitov , Kirill Zainoulline

In the first half of this article we define a new weight homology functor on Voevodsky's category of effective motives, and investigate some of its properties. In special cases we recover Gillet-Soul\'e's weight homology, and Geisser's…

Algebraic Geometry · Mathematics 2014-11-24 Shane Kelly , Shuji Saito

We prove that graded $k$-Schur functions are $G$-equivariant Euler characteristics of vector bundles on the flag variety, settling a conjecture of Chen-Haiman. We expose a new miraculous shift invariance property of the graded $k$-Schur…

Combinatorics · Mathematics 2018-04-12 Jonah Blasiak , Jennifer Morse , Anna Pun , Daniel Summers

Let $G/H$ be a homogeneous variety, and let $X$ be a $G$-equivariant embedding of $G/H$such that the number of $G$-orbits in $X$ is finite. We show that the equivariant Borel-Moore homology of $X$ has a filtration with associated graded…

Algebraic Geometry · Mathematics 2019-06-06 Aram Bingham , Mahir Bilen Can , Yıldıray Ozan