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Related papers: Involutions in Coxeter groups

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In this paper we give a classification of classes of involutions on an automorphism group of an octonion algebra over fields of characteristic 2, and describe the classes of their fixed point groups.

Group Theory · Mathematics 2016-11-30 John Hutchens , Nathaniel Schwartz

We prove that two reflection factorizations of a parabolic quasi-Coxeter element in a finite Coxeter group belong to the same Hurwitz orbit if and only if they generate the same subgroup and have the same multiset of conjugacy classes. As a…

Combinatorics · Mathematics 2024-02-07 Theo Douvropoulos , Joel Brewster Lewis

We introduce and study a combinatorially defined notion of root basis of a (real) root system of a possibly infinite Coxeter group. Known results on conjugacy up to sign of root bases of certain irreducible finite rank real root systems are…

Group Theory · Mathematics 2010-11-11 Matthew Dyer

We survey the existing parts of a classification of finite groups generated by orthogonal transformations in a finite-dimensional Euclidean space whose fixed point subspace has codimension one or two and extend it to a complete…

Group Theory · Mathematics 2017-11-02 Christian Lange , Marina A. Mikhailova

We study graph complexes related to configuration spaces and diffeomorphism groups of highly connected manifolds of odd dimension. In particular we compute the cohomology in the "high genus" limit. This paper is a continuation of previous…

Quantum Algebra · Mathematics 2022-08-22 Simon Brun , Thomas Willwacher

We introduce a notion of essential hyperbolic Coxeter polytope as a polytope which fits some minimality conditions. The problem of classification of hyperbolic reflection groups can be easily reduced to classification of essential Coxeter…

Combinatorics · Mathematics 2019-10-25 Anna Felikson , Pavel Tumarkin

Gaussian graphical models have become a well-recognized tool for the analysis of conditional independencies within a set of continuous random variables. From an inferential point of view, it is important to realize that they are composite…

Statistics Theory · Mathematics 2013-10-30 Jan Draisma , Sonja Kuhnt , Piotr Zwiernik

Motivated by work of Coxeter (1957), we study a class of algebras associated to Coxeter groups, which we term 'generalized nil-Coxeter algebras'. We construct the first finite-dimensional examples other than usual nil-Coxeter algebras;…

Rings and Algebras · Mathematics 2022-04-19 Apoorva Khare

In [BGLM] and [GLNP] it was conjectured that if $H$ is a simple Lie group of real rank at least 2, then the number of conjugacy classes of (arithmetic) lattices in $H$ of covolume at most $x$ is $x^{(\gamma(H)+o(1))\log x/\log\log x}$ where…

Group Theory · Mathematics 2018-04-03 Mikhail Belolipetsky , Alex Lubotzky

We describe the rings of invariants for the finite orthogonal groups of plus type in odd characteristic acting on the defining representations. We also describe the invariants of the corresponding Sylow subgroups in the defining…

Commutative Algebra · Mathematics 2026-03-12 H. E. A. Campbell , R. James Shank , David L. Wehlau

We use geometry of Davis complex of a Coxeter group to prove the following result: if G is an infinite indecomposable Coxeter group and $H\subset G$ is a finite index reflection subgroup then the rank of H is not less than the rank of G.…

Group Theory · Mathematics 2019-10-25 Anna Felikson , Pavel Tumarkin

We prove the dichotomy that every Coxeter group either has a strongly solid group von Neumann algebra or contains the product of an infinite cyclic group and a free group of rank 2. This generalizes the same dichotomy for right-angled…

Operator Algebras · Mathematics 2025-12-02 Martín Blufstein , Katherine Goldman , Koichi Oyakawa

The reflections in a Coxeter group are defined as conjugates of a single generator, and thus admit palindromic expressions as products of generators. Our main result gives closed formulas providing a palindromic reduced expression for each…

Combinatorics · Mathematics 2025-04-08 Elizabeth Milićević

The following results are proved: The center of any finite index subgroup of an irreducible, infinite, non-affine Coxeter group is trivial; Any finite index subgroup of an irreducible, infinite, non-affine Coxeter group cannot be expressed…

Group Theory · Mathematics 2007-05-23 Dongwen Qi

We prove that a finite complex reflection group has a generalized involution model, as defined by Bump and Ginzburg, if and only if each of its irreducible factors is either $G(r,p,n)$ with $\gcd(p,n)=1$; $G(r,p,2)$ with $r/p$ odd; or…

Representation Theory · Mathematics 2011-04-20 Eric Marberg

The $c_2$ invariant is an arithmetic graph invariant introduced by Schnetz and developed by Brown and Schnetz in order to better understand Feynman integrals. This document looks at the special case where the graph in question is a…

Combinatorics · Mathematics 2016-01-01 Karen Yeats

In this work, we establish a relationship between the sum of irreducible character degrees and the number of twisted involutions associated with the automorphisms of a finite group. We develop algorithmic frameworks for evaluating these…

Representation Theory · Mathematics 2026-05-25 Venkata Subbaiah Yerrapati , Rahul Dixit , Ajay Kumar Shukla

There has been recent interest in novel Clifford geometric invariants of linear transformations. This motivates the investigation of such invariants for a certain type of geometric transformation of interest in the context of root systems,…

Machine Learning · Computer Science 2024-05-28 Siqi Chen , Pierre-Philippe Dechant , Yang-Hui He , Elli Heyes , Edward Hirst , Dmitrii Riabchenko

We investigate the representations and the structure of Hecke algebras associated to certain finite complex reflection groups. We first describe computational methods for the construction of irreducible representations of these algebras,…

Representation Theory · Mathematics 2019-02-20 Gunter Malle , Jean Michel

For well-generated complex reflection groups, Chapuy and Stump gave a simple product for a generating function counting reflection factorizations of a Coxeter element by their length. This is refined here to record the number of reflections…

Combinatorics · Mathematics 2017-08-22 Elise delMas , Thomas Hameister , Victor Reiner