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Related papers: Decomposition numbers for perverse sheaves

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The aim of this paper is to identify a certain tensor category of perverse sheaves on the real loop Grassmannian of a real form $G_{\mathbb R}$ of a connected reductive complex algebraic group $G$ with the category of finite-dimensional…

Algebraic Geometry · Mathematics 2007-05-23 David Nadler

These notes aim to give a first introduction to intersection cohomology and perverse sheaves with applications to representation theory or quantum groups in mind.

Representation Theory · Mathematics 2007-05-23 Konstanze Rietsch

We define and describe the properties of a class of perverse sheaves which is very useful when the base ring is not a field.

Algebraic Geometry · Mathematics 2024-07-10 David B. Massey

This paper is the first in a series. The main goal of the series is to present a geometric construction of certain remarkable tensor categories arising from quantum groups coresponding to the value of deformation parameter $q$ equal to a…

High Energy Physics - Theory · Physics 2008-02-03 M. Finkelberg , V. Schechtman

In this paper, we carry out several computations involving graded (or $\mathbb{G}_{\mathrm{m}}$-equivariant) perverse-coherent sheaves on the nilpotent cone of a reductive group in good characteristic. In the first part of the paper, we…

Representation Theory · Mathematics 2019-03-11 Pramod N. Achar , William D. Hardesty

In this paper we give a geometric version of the Satake isomorphism. Given a connected complex reductive algebraic group, we show that the category of representations of its Langlands dual is naturally equivalent to a certain category of…

Representation Theory · Mathematics 2018-02-14 I. Mirkovic , K. Vilonen

Let H be a Hecke algebra arising as an endomorphism algebra of the representation of a Chevalley group G over F_q induced by a unipotent cuspidal representation of a Levi quotient L of a parabolic subgroup. We assume that L is not a torus.…

Representation Theory · Mathematics 2015-01-30 G. Lusztig

Let $G$ be a simple simply connected complex algebraic group and let $\mathfrak{g}_*$ be a $\mathbf{Z}/m$-grading on its Lie algebra $\mathfrak{g}$. In a recent series of articles, G. Lusztig and Z. Yun, studied the classification of simple…

Representation Theory · Mathematics 2022-03-14 Wille Liu

We prove an isomorphism for simple perverse sheaves on the affine Grassmannian of a connected reductive algebraic group that is a geometric counterpart (in light of the Finkelberg-Mirkovi\'c conjecture) of the Steinberg tensor product…

Representation Theory · Mathematics 2022-02-17 Pramod N. Achar , Simon Riche

We describe the equivariant cohomology of cofibers of spherical perverse sheaves on the affine Grassmannian of a reductive algebraic group in terms of the geometry of the Langlands dual group. In fact we give two equivalent descriptions:…

Representation Theory · Mathematics 2014-03-25 Victor Ginzburg , Simon Riche

The purpose of this paper is to introduce and study certain irreducible perverse l-adic sheaves on a reductive group G over a finite field (we call them gamma-sheaves). One can construct such a sheaf starting with (almost) every…

Algebraic Geometry · Mathematics 2007-05-23 Alexander Braverman , David Kazhdan

We generalize the decomposition theorem for perverse sheaves to Artin stacks with affine stabilizers over finite fields.

Algebraic Geometry · Mathematics 2019-12-19 Shenghao Sun

We study perverse sheaves of categories their connections to classical algebraic geometry. We show how perverse sheaves of categories encode naturally derived categories of coherent sheaves on $\mathbb{P}^1$ bundles, semiorthogonal…

Algebraic Geometry · Mathematics 2019-07-01 Andrew Harder , Ludmil Katzarkov

We consider categories of generalized perverse sheaves, with relaxed constructibility conditions, by means of the process of gluing $t$-structures and we exhibit explicit abelian categories defined in terms of standard sheaves categories…

Algebraic Geometry · Mathematics 2007-05-23 F. Gudiel-Rodriguez , L. Narvaez-Macarro

An intrinsic construction of the tensor category of finite dimensional representations of the Langlands dual group of G in terms of a tensor category of perverse sheaves on the loop group, LG, is given. The construction is applied to the…

alg-geom · Mathematics 2008-02-03 Victor Ginzburg

We consider the category of perverse sheaves on a complex vector space smooth with respect to a stratification given by an arrangement of hyperplanes with real equations. As shown in an earlier wotk of two of the authors, this category can…

Algebraic Topology · Mathematics 2022-06-28 Michael Finkelberg , Mikhail Kapranov , Vadim Schechtman

On the complement $X= {\mathbb C}^2 - \bigcup_{i=1}^n L_i$ to a central plane line arrangement $\bigcup_{i=1}^n L_i \subset {\mathbb C}^2$, a locally constant sheaf of complex vector spaces $\mathcal L_a$ is associated to any multi-index $a…

Algebraic Topology · Mathematics 2017-03-09 Rikard Bøgvad , Iara Gonçalves

The category of perverse sheaves on the affine Grassmannian of a complex reductive group $G$ gives a canonical geometric construction of the split form of the Langlands dual group $\check G_\bZ$ over the integers. Given a field $k$, we give…

Representation Theory · Mathematics 2008-11-18 Vivek Dhand

Perverse schobers are categorifications of perverse sheaves. We construct a perverse schober on a partial compactification of the stringy K\"ahler moduli space (SKMS) associated by Halpern-Leistner and Sam to a quasi-symmetric…

Algebraic Geometry · Mathematics 2019-09-06 Špela Špenko , Michel Van den Bergh

In this article we address the length of perverse sheaves arising as direct images of rank one local systems on complements of hyperplane arrangements. In the case of a cone over an essential line arrangement with at most triple points, we…

Algebraic Topology · Mathematics 2019-09-10 Nero Budur , Yongqiang Liu