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Let D be a connected component of a reductive group over an algebraically closed field. We define a surjective map from the unipotent character sheaves on D to the set of strata of D, extending an earlier result which applied to connected…

Representation Theory · Mathematics 2023-04-19 G. Lusztig

We develop the rudiments of a finite-dimensional representation theory of groups over idempotent semifields by considering linear actions on tropical linear spaces. This can be considered a tropical representation theory, a characteristic…

Representation Theory · Mathematics 2018-10-23 Noah Giansiracusa , Jacob Manaker

We present an exposition of our ongoing project in a new area of applicable mathematics: practical computation with finitely generated linear groups over infinite fields. Methodology and algorithms available for practical computation in…

Group Theory · Mathematics 2021-10-01 A. S. Detinko , D. L. Flannery

We define a class of pre-ordered abelian groups that we call finite-by-Presburger groups, and prove that their theory is model-complete. We show that certain quotients of the multiplicative group of a local field of characteristic zero are…

Logic · Mathematics 2016-03-30 Jamshid Derakhshan , Angus Macintyre

We show that any complex (respectively real) representation of finite group naturally generates a open-closed (respectively Klein) topological field theory over complex numbers. We relate the 1-point correlator for the projective plane in…

Representation Theory · Mathematics 2011-07-19 Sergey A. Loktev , Sergey M. Natanzon

In this paper we show how a theorem of Jantzen relating the character of a finite dimensional irreducible representation of a disconnected semisimple algebraic group on elements outside the connected component of identity to character of an…

Representation Theory · Mathematics 2007-09-19 Shrawan Kumar , George Lusztig , Dipendra Prasad

In this lecture, we survey a number of recent results and developments regarding the representation theory of infinite-dimensional quantum groups (quantum affine algebras and related algebras), as well as their connections with cluster…

Representation Theory · Mathematics 2025-10-09 David Hernandez

Let $G$ be a simple algebraic group of exceptional type over an algebraically closed field of characteristic $p > 0$. This paper continues a long-standing effort to classify the connected reductive subgroups of $G$. Having previously…

Group Theory · Mathematics 2023-04-18 Alastair J. Litterick , Adam R. Thomas

We prove that the homology groups of any connected reductive group over a field with coefficients in the Steinberg representation vanish in a range. The generalizes work of Ash-Putman-Sam on the classical split groups. We state a…

Algebraic Topology · Mathematics 2025-09-03 Jeremy Miller , Peter Patzt , Andrew Putman

Recently there has been a lot of research and progress in profinite groups. We survey some of the new results and discuss open problems. A central theme is decompositions of finite groups into bounded products of subsets of various kinds…

Group Theory · Mathematics 2012-02-23 Nikolay Nikolov

In this paper we define a new algebraic object: the disguised-groups. We show the main properties of the disguised-groups and, as a consequence, we will see that disguised-groups coincide with regular semigroups. We prove many of the…

Group Theory · Mathematics 2020-06-08 Eduardo Blanco-Gómez

In this article we extend independent results of Lusztig and H\'ezard concerning the existence of irreducible characters of finite reductive groups, (defined in good characteristic and arising from simple algebraic groups), satisfying a…

Representation Theory · Mathematics 2014-04-01 Jay Taylor

In this paper we determine the representation type of some algebras of infinite matrices continuously controlled at infinity by a compact metrizable space. We explicitly classify their finitely presented modules in the finite and tame…

Representation Theory · Mathematics 2007-05-23 Fernando Muro

The Cremona group of rank n over a field k is the group of birational automorphisms of the n-dimensional projective space over the field k. We study the minimal dimension such that all finite subgroups of the Cremona group have a faithful…

Algebraic Geometry · Mathematics 2025-07-08 Alexander Duncan , Bailey Heath , Christian Urech

We study unitary representations of semidirect products of a compact quantum group with a finite group. We give a classification of all irreducible unitary representations, a description of the conjugate representation of irreducible…

Operator Algebras · Mathematics 2020-09-28 Hua Wang

We classify all finite groups of essential dimension 2 over an algebraically closed field of characteristic 0.

Algebraic Geometry · Mathematics 2013-08-21 Alexander Duncan

This abstract presents (without proofs) some new results on commutativity degree of finite groups.

Group Theory · Mathematics 2010-09-29 Rajat Kanti Nath , Ashish Kumar Das

We introduce a linearized version of group field theory. It can be viewed either as a group field theory over the additive group of a vector space or as an asymptotic expansion of any group field theory around the unit group element. We…

High Energy Physics - Theory · Physics 2014-11-20 Joseph Ben Geloun , Thomas Krajewski , Jacques Magnen , Vincent Rivasseau

We close a gap in the explicit determination of the generalized Springer correspondence for a connected reductive group in good characteristic.

Representation Theory · Mathematics 2016-09-05 G. Lusztig

In this paper we study groups definable in existentially closed partial differential fields of characteristic 0 with an automorphism which commutes with the derivations. In particular, we study Zariski dense definable subgroups of simple…