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Related papers: Notes on character sheaves

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Building on a geometric counterpart of Steinberg's tensor product formula for simple representations of a connected reductive algebraic group $G$ over a field of positive characteristic, and following an idea of…

Representation Theory · Mathematics 2024-03-26 Pramod N. Achar , Simon Riche

In this paper we introduce a new ingredient, invariant systems of differential equations, to our study of character sheaves on graded Lie algebras. The character sheaves we construct in this paper, together with the ones constructed in…

Representation Theory · Mathematics 2024-10-29 Kari Vilonen , Ting Xue

We prove a weak version of Lusztig's conjecture on explicit description of the asymptotic Hecke algebras (both finite and affine), and explain its relation to Lusztig's classification of character sheaves.

Representation Theory · Mathematics 2007-10-29 Roman Bezrukavnikov , Michael Finkelberg , Victor Ostrik

We prove a conjecture by Lusztig, which describes the tensor categories of perverse sheaves on affine flag manifolds, with tensor structure provided by truncated convolution, in terms of the Langlands dual group. We also give a geometric…

Representation Theory · Mathematics 2012-01-04 Roman Bezrukavnikov

We address some questions posed by Goss related to the modularity of Drinfeld modules of rank 1 defined over the field of rational functions in one variable with coefficients in a finite field. For each positive characteristic valued…

Number Theory · Mathematics 2017-05-15 Rudolph Perkins

We present a brief summary of the recent discovery of direct tensorial analogue of characters. We distinguish three degrees of generalization: (1) $c$-number Kronecker characters made with the help of symmetric group characters and…

High Energy Physics - Theory · Physics 2018-12-11 H. Itoyama , A. Mironov , A. Morozov

We give a description of certain categories of equivariant coherent sheaves on Grothendieck's resolution in terms of the categorical affine Hecke algebra of Soergel. As an application, we deduce a relationship of these coherent sheaf…

Algebraic Geometry · Mathematics 2011-08-22 Christopher Dodd

In the first part, we construct a new isomorphism between the endomorphism algebra of an induced cuspidal character sheaf and the group algebra of the relative Weyl group involved. We show it differs from the isomorphism of Lusztig by a…

Group Theory · Mathematics 2007-05-23 Cedric Bonnafe

We give a description of simple functors taking finitely generated values, from a small additive category to the category of vector spaces over a field. This result is analogous to Steinberg's tensor product theorems in group representation…

Representation Theory · Mathematics 2021-05-05 Aurélien Djament , Antoine Touzé , Christine Vespa

We propose a categorification of the Chern character that refines earlier work of To\"en and Vezzosi and of Ganter and Kapranov. If X is an algebraic stack, our categorified Chern character is a symmetric monoidal functor from a category of…

K-Theory and Homology · Mathematics 2017-01-17 Marc Hoyois , Sarah Scherotzke , Nicolò Sibilla

We give a Tannakian description for categories of l-adic perverse sheaves on semiabelian varieties which combines a construction of Gabber and Loeser for algebraic tori with a generic vanishing theorem for the cohomology of constructible…

Algebraic Geometry · Mathematics 2015-03-30 Thomas Krämer

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

In this paper, we prove Lusztig's conjecture for finite special linear groups, i.e., we show that characteristic functions of character sheaves coincide with almost characters up to scalar constants, under the condition that the…

Representation Theory · Mathematics 2007-05-23 Toshiaki Shoji

We study a category of Iwahori-equivariant modular perverse sheaves on some avatar of the semi-infinite flag variety, by adapting the work of Arkhipov-Bezrukavnikov-Braverman-Gaitsgory-Mirkovi\'c. We then construct a functor between the…

Representation Theory · Mathematics 2026-04-02 Emilien Zabeth

In this paper we provide a "combinatorial" description of the category of tilting perverse sheaves on the affine flag variety of a reductive algebraic group, and its free-monodromic variant, with coefficients in a field of positive…

Representation Theory · Mathematics 2024-07-08 Roman Bezrukavnikov , Simon Riche

We study connections between the topology of generic character varieties of fundamental groups of punctured Riemann surfaces, Macdonald polynomials, quiver representations, Hilbert schemes on surfaces, modular forms and multiplicities in…

Representation Theory · Mathematics 2011-09-29 Tamas Hausel , Emmanuel Letellier , Fernando Rodriguez-Villegas

The theory of character sheaves on a reductive group is extended to a class of varieties which includes the strata of the De Concini-Procesi completion of an adjoint group.

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

Let $k$ be a field of characteristic $0$ endowed with a complex embedding $\sigma: k \hookrightarrow \mathbb{C}$. In this paper we complete the construction of the six functor formalism on perverse Nori motives over quasi-projective…

Algebraic Geometry · Mathematics 2026-02-11 Luca Terenzi

Let $X \subset \mathbb{P}^{n+1}$ be a smooth Fano hypersurface of dimension $n$ and degree $d$. The derived category of coherent sheaves on $X$ contains an interesting subcategory called the Kuznetsov component $\mathcal{A}_X$. We show that…

Algebraic Geometry · Mathematics 2022-08-30 Dmitrii Pirozhkov

In this paper we construct full support character sheaves for stably graded Lie algebras. Conjecturally these are precisely the cuspidal character sheaves. Irreducible representations of Hecke algebras associated to complex reflection…

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