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Related papers: Character sheaves on certain spherical varieties

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In this paper we develop the theory of perverse sheaves on Artin stacks continuing the study in "The six operations for sheaves on Artin stacks I: Finite Coefficients" and "The six operations for sheaves on Artin stacks II: Adic…

Algebraic Geometry · Mathematics 2007-05-23 Yves Laszlo , Martin Olsson

We give an explicit description of character sheaves for the symmetric pairs associated to inner involutions of the special linear groups. We make use of the general strategy given in [VX1] and central character consideration. We also…

Representation Theory · Mathematics 2025-03-25 Kari Vilonen , Ting Xue

We determine versal non-commutative deformations of some simple collections in the categories of perverse coherent sheaves arising from tilting generators for projective morphisms.

Algebraic Geometry · Mathematics 2018-06-14 Yujiro Kawamata

We prove a microlocal characterisation of character sheaves on a reductive Lie algebra over an algebraically closed field of sufficiently large positive characteristic: a perverse irreducible G-equivariant sheaf is a character sheaf if and…

Representation Theory · Mathematics 2024-05-14 Tong Zhou

In the first section we study a functor of Bezrukavnikov, Finkelberg and Ostrik defined on character sheaves; we compute it in a Grothendieck group taking weights into account. In the second section we enlarge the class of character sheaves…

Representation Theory · Mathematics 2008-05-07 G. Lusztig

Exotic sheaves are certain complexes of coherent sheaves on the cotangent bundle of the flag variety of a reductive group. They are closely related to perverse-coherent sheaves on the nilpotent cone. This expository article includes the…

Representation Theory · Mathematics 2014-09-26 Pramod N. Achar

We consider non-commutative deformations of sheaves on algebraic varieties. We develop some tools to determine parameter algebras of versal non-commutative deformations for partial simple collections and the structure sheaves of smooth…

Algebraic Geometry · Mathematics 2021-08-31 Yujiro Kawamata

It is well known that the category of quasi-coherent sheaves on a gerbe banded by a diagonalizable group decomposes according to the characters of the group. We establish the corresponding decomposition of the unbounded derived category of…

Algebraic Geometry · Mathematics 2019-02-20 Daniel Bergh , Olaf M. Schnürer

Inspired by the foundational work of Bezrukavnikov and Chan \cite{BC24} on character sheaves for parahoric subgroups and an alternative interpretation of deep level Deligne-Lusztig characters in \cite{Nie_24}, we present a parallel but…

Representation Theory · Mathematics 2025-09-24 Alexander B. Ivanov , Sian Nie , Zhihang Yu

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

We define and study convolution of parabolic character sheaves. As an application we attach to any parabolic character sheaf the orbit of a tame local system on the maximal torus under a subgroup of the Weyl group.

Representation Theory · Mathematics 2007-05-23 G. Lusztig

We classify morphisms from proper varieties to Brauer-Severi varieties, which generalizes the classical correspondence between morphisms to projective space and globally generated invertible sheaves. As an application, we study del Pezzo…

Algebraic Geometry · Mathematics 2017-02-10 Christian Liedtke

We conjecture that any perverse sheaf on a compact aspherical K\"ahler manifold has non-negative Euler characteristic. This extends the Singer-Hopf conjecture in the K\"ahler setting. We verify the stronger conjecture when the manifold X…

Algebraic Geometry · Mathematics 2025-01-31 Donu Arapura , Botong Wang

The geometric Satake isomorphism is an equivalence between the categories of spherical perverse sheaves on affine Grassmanian and the category of representations of the Langlands dual group. We provide a similar description for derived…

Representation Theory · Mathematics 2020-02-13 Sergey Arkhipov , Roman Bezrukavnikov

A class of perverse sheaves on framed representation varieties of the Jordan quiver is defined. Its relationship with product of symmetric groups, tensor product of Schur algebras, and tensor product of Fock spaces are addressed.

Representation Theory · Mathematics 2012-09-18 Yiqiang Li

On a complex contact manifold, or complex symplectic manifold with weight-1 circle action, we construct a sheaf of stable categories carrying a t-structure which is locally equivalent to a microlocalization of the perverse t-structure.

Symplectic Geometry · Mathematics 2025-12-17 Laurent Côté , Christopher Kuo , David Nadler , Vivek Shende

Let H be an arrangement of real hyperplanes in R^n. The complexification of H defines a natural stratification of C^n. We denote by Perv(C^n, H) the category of perverse sheaves on C^n smooth with respect to this stratification. We give a…

Algebraic Topology · Mathematics 2015-02-04 Mikhail Kapranov , Vadim Schechtman

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

We give a geometric construction of tilting perverse sheaves using stratified Morse theory, torus actions, and nearby cycles.

Representation Theory · Mathematics 2007-05-23 David Nadler

Another introduction to perverse sheaves with some exercises. Expanded version of five lectures at the 2015 PCMI.

Algebraic Geometry · Mathematics 2016-11-15 Mark Andrea A. de Cataldo