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Related papers: On conjugacy classes in a reductive group

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Suppose that $\tilde{G}$ is a connected reductive group defined over a field $k$, and $\Gamma$ is a finite group acting via $k$-automorphisms of $\tilde{G}$ satisfying a certain quasi-semisimplicity condition. Then the connected part of the…

Representation Theory · Mathematics 2014-07-28 Jeffrey D. Adler , Joshua M. Lansky

In an earlier paper by Kazhdan and the author, a map from the set of unipotent classes in a reductive connected group over C to the conjugacy classes in the Weyl group was defined. Here we present some experimental evidence for a possibly…

Representation Theory · Mathematics 2009-07-24 G. Lusztig

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

There are several graphs defined on groups. Among them we consider graphs whose vertex set consists conjugacy classes of a group $G$ and adjacency is defined by properties of the elements of conjugacy classes. In particular, we consider…

Group Theory · Mathematics 2024-03-20 P. J. Cameron , F. E. Jannat , R. K. Nath , R. Sharafdini

Let $S$ be a semigroup. The elements $a,b\in S$ are called primarily conjugate if $a=xy$ and $b=yx$ for certain $x,y\in S$. The relation of conjugacy is defined as the transitive closure of the relation of primary conjugacy. In the case…

Group Theory · Mathematics 2007-05-23 Ganna Kudryavtseva

Let G be a finite group. An element x in G is a real element if x is conjugate to its inverse in G. For x in G, the conjugacy class x^G is said to be a real conjugacy class if every element of x^G is real. We show that if 4 divides no real…

Group Theory · Mathematics 2013-06-28 Hung P. Tong-Viet

We express the set of representations from a cyclic $p$-group to a connected $p$-compact group in terms of the associated reflection group and compute its cardinality for each exotic $p$-compact group.

Algebraic Topology · Mathematics 2025-10-14 José Cantarero , Bernardo Villarreal

Many results have been established that show how arithmetic conditions on conjugacy class sizes affect group structure. A conjugacy class in $G$ is called vanishing if there exists some irreducible character of $G$ which evaluates to zero…

Group Theory · Mathematics 2015-09-23 Julian Brough

Let G be a simple algebraic group over an algebraically closed field k of bad characteristic. We classify the spherical unipotent conjugacy classes of G. We also show that if the characteristic of k is 2, then the fixed point subgroup of…

Group Theory · Mathematics 2009-06-30 Mauro Costantini

A new general formula for the number of conjugacy classes of subgroups of given index in a finitely generated group is obtained.

Combinatorics · Mathematics 2007-05-23 A. D. Mednykh

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 classify the finite groups $G$ which satisfies the condition that every complex irreducible character,whose degree's square doesn't divide the index of its kernel in $G$, lies in the same Galois conjugacy class.

Group Theory · Mathematics 2022-08-17 Yu Zeng , Dongfang Yang

Let G be a simple complex algebraic group. By using a notion of a G-category we define invariants of tangles with flat G-connections in their complements. We also show that quantized universal enveloping algebras at roots of unity provide…

Quantum Algebra · Mathematics 2010-08-10 R. Kashaev , N. Reshetikhin

Let G be a reductive linear algebraic group over an algebraically closed field of characteristic p > 0. A subgroup of G is said to be separable in G if its global and infinitesimal centralizers have the same dimension. We study the…

Group Theory · Mathematics 2008-08-12 Michael Bate , Benjamin Martin , Gerhard Roehrle , Rudolf Tange

We give an apriori description of a set of irreducible representations of a Weyl group which parametrize the nilpotent orbits in the Lie algebra of a connected reductive group in arbitrary characteristic. We also answer a question of Serre…

Representation Theory · Mathematics 2008-11-25 G. Lusztig

Let $G$ be a connected reductive algebraic group with simply connected derived subgroup. Over the complex numbers there exists a local method to study the geometric properties of a point $g$ in the closure of a Jordan class of $G$ in terms…

Representation Theory · Mathematics 2025-08-05 Filippo Ambrosio

We define noncommutative deformations $W_q^s(G)$ of algebras of functions on certain (finite coverings of) transversal slices to the set of conjugacy classes in an algebraic group $G$ which play the role of Slodowy slices in algebraic group…

Representation Theory · Mathematics 2015-06-29 A. Sevostyanov

We show that the stable module $\infty$-category of a finite group $G$ decomposes in three different ways as a limit of the stable module $\infty$-categories of certain subgroups of $G$. Analogously to Dwyer's terminology for homology…

Representation Theory · Mathematics 2020-09-25 Joshua Hunt

We compute the number of orbit types for simply connected simple algebraic groups over algebraically closed fields as well as for compact simply connected simple Lie groups. We also compute the number of orbit types for the adjoint action…

Group Theory · Mathematics 2013-03-19 Anirban Bose

By algebraic group theory, there is a map from the semisimple conjugacy classes of a finite group of Lie type to the conjugacy classes of the Weyl group. Picking a semisimple class uniformly at random yields a probability measure on…

Number Theory · Mathematics 2007-05-23 Jason Fulman