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Related papers: Character sheaves and generalizations

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In this paper we propose a construction of generic character sheaves on reductive groups over finite local rings at even levels, whose characteristic functions are higher Deligne--Lusztig characters when the parameters are generic. We…

Representation Theory · Mathematics 2018-05-01 Zhe Chen

We define the notion of character sheaf on a possibly disconnected reductive group. We show that the restriction functor carries a character sheaf to a direct sum of character sheaves.

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

Mirkovi\'c introduced the notion of character sheaves on a Lie algebra. Due to their simple geometric characterization, character sheaves on Lie algebras can be thought of as a simplified model for Lusztig's theory of character sheaves on…

Representation Theory · Mathematics 2024-07-23 Colton Sandvik

These notes are our contribution to the Proceedings of the ICM 2026. We discuss some results we have obtained (in part jointly with coauthors) regarding the representation theory of reductive algebraic groups over algebraically closed…

Representation Theory · Mathematics 2025-11-10 Pramod N. Achar , Simon Riche

We construct a supercharacter theory for the group of invertible elements of a reduced algebra. For the case of the triangular group, we obtain the formula for values of supercharacters on superclasses.

Representation Theory · Mathematics 2015-06-10 A. N. Panov

In this paper we provide a geometric framework for the study of characters of depth-zero representations of unramified groups over local fields with finite residue fields which is built directly on Lusztig's theory of character sheaves for…

Representation Theory · Mathematics 2007-05-23 Anne-Marie Aubert , Clifton Cunningham

Let A be a character sheaf on a reductive connected group G over an algebraically closed field. Assuming that the characteristic is not bad, we show that for certain conjugacy classes D in G the restriction of A to D is a local system up to…

Representation Theory · Mathematics 2012-06-22 G. Lusztig

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 give a definition of character sheaves on the group compactification which is equivalent to Lusztig's definition in \cite{L3}. We also prove some properties of the character sheaves on the group compactification.

Representation Theory · Mathematics 2007-05-23 Xuhua He

We apply the ideas of derived algebraic geometry and topological field theory to the representation theory of reductive groups. Our focus is the Hecke category of Borel-equivariant D-modules on the flag variety of a complex reductive group…

Representation Theory · Mathematics 2015-02-11 David Ben-Zvi , David Nadler

We establish a Springer theory for classical symmetric pairs. We give an explicit description of character sheaves in this setting. In particular we determine the cuspidal character sheaves.

Representation Theory · Mathematics 2025-03-25 Kari Vilonen , Ting Xue , with an appendix by Dennis Stanton

The character theory of finite groups has numerous basic questions that are often already quite involved: enumerating of irreducible characters, their character formulas, point-wise product decompositions, and restriction/induction between…

Representation Theory · Mathematics 2018-10-03 Farid Aliniaeifard , Nathaniel Thiem

This article is based on lectures given by the authors in 2005 and 2006. Our first goal is to present an introduction to the orbit method with an emphasis on the character theory of finite nilpotent groups. The second goal (motivated by a…

Representation Theory · Mathematics 2010-11-24 Mitya Boyarchenko , Vladimir Drinfeld

We show that certain Iwahori-Hecke algebras with unequal parameters can be realized in the framework of parabolic character sheaves.

Representation Theory · Mathematics 2025-04-04 G. Lusztig

This paper is an introduction to the use of perverse sheaves with positive characteristic coefficients in modular representation theory. In the first part, we survey results relating singularities in finite and affine Schubert varieties and…

Representation Theory · Mathematics 2014-10-07 Daniel Juteau , Carl Mautner , Geordie Williamson

With a view to determining character values of finite reductive groups at unipotent elements, we prove a number of results concerning inner products of generalised Gelfand-Graev characters with characteristic functions of character sheaves,…

Representation Theory · Mathematics 2015-02-03 François Digne , Gustav Lehrer , Jean Michel

In this paper we prove a new characterization of the distinguished unipotent orbits of a connected reductive group over an algebraically closed field of characteristic 0. For classical groups we prove the characterization by a combinatorial…

Representation Theory · Mathematics 2024-09-11 Alexander Bertoloni Meli , Teruhisa Koshikawa , Jonathan Leake

Using the character expansion method, we generalize several well-known integrals over the unitary group to the case where general complex matrices appear in the integrand. These integrals are of interest in the theory of random matrices and…

Mathematical Physics · Physics 2008-11-26 B. Schlittgen , T. Wettig

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

This paper concerns character sheaves of connected reductive algebraic groups defined over non-Archimedean local fields and their relation with characters of smooth representations. Although character sheaves were devised with characters of…

Representation Theory · Mathematics 2008-12-31 Clifton Cunningham , Hadi Salmasian