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Related papers: A Note on Parabolic Subgroups of a Coxeter Group

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Let $(W,S)$ be a Coxeter system with $I\subseteq S$ such that the parabolic subgroup $W_I$ is finite. Associated to this data there is a \textit{Hecke algebra} $\scH$ and a \textit{parabolic Hecke algebra}…

Representation Theory · Mathematics 2011-10-31 Peter Abramenko , James Parkinson , Hendrik Van Maldeghem

One can observe that Coxeter groups and right-angled Artin groups share the same solution to the word problem. On the other hand, in his study of reflection subgroups of Coxeter groups Dyer introduces a family of groups, which we call Dyer…

Group Theory · Mathematics 2022-12-22 Luis Paris , Mireille Soergel

The main goal of this note is to determine and to count the normal subgroups of a ZM-group. We also indicate some necessary and sufficient conditions such that the normal subgroups of a ZM-group form a chain.

Group Theory · Mathematics 2015-02-18 Marius Tarnauceanu

A Coxeter system is an ordered pair (W,S) where S is the generating set in a particular type of presentation for the Coxeter group W. A subgroup of W is called special if it is generated by a subset of S. Amalgamated product decompositions…

Group Theory · Mathematics 2007-05-23 Michael L. Mihalik , Steven Tschantz

Given a function defined over a parabolic subgroup of a Coxeter group, equidistributed with the length, we give a procedure to construct a function over the entire group, equidistributed with the length. Such a procedure permits to define…

Combinatorics · Mathematics 2018-08-23 Paolo Sentinelli

In this note we give some new results concerning the subgroup commutativity degree of a finite group $G$. These are obtained by considering the minimum of subgroup commutativity degrees of all sections of $G$.

Group Theory · Mathematics 2018-02-13 Marius Tărnăuceanu

The conjugacy classes of so-called special involutions parameterize the constituents of the action of a finite Coxeter group on the cohomology of the complement of its complexified hyperplane arrangement. In this note we give a short…

Group Theory · Mathematics 2007-05-23 Goetz Pfeiffer , Gerhard Roehrle

For right-angled Coxeter groups $W_{\Gamma}$, we obtain a condition on $\Gamma$ that is necessary and sufficient to ensure that $W_{\Gamma}$ is thick and thus not relatively hyperbolic. We show that Coxeter groups which are not thick all…

Group Theory · Mathematics 2017-03-22 Jason Behrstock , Mark F. Hagen , Alessandro Sisto , Pierre-Emmanuel Caprace

We revisit the structure of the normalizer $N_W(P)$ of a parabolic subgroup $P$ in a finite Coxeter group $W$, originally described by Howlett. Building on Howlett's Lemma, which provides canonical complements for reflection subgroups, and…

Group Theory · Mathematics 2026-03-30 J. Matthew Douglass , Götz Pfeiffer , Gerhard Roehrle

We consider a cocompact discrete reflection group $W$ of a CAT(0) space $X$. Then $W$ becomes a Coxeter group. In this paper, we study an analogy between the Davis-Moussong complex $\Sigma(W,S)$ and the CAT(0) space $X$, and show several…

Group Theory · Mathematics 2010-11-30 Tetsuya Hosaka

We show that a group that is hyperbolic relative to strongly shortcut groups is itself strongly shortcut, thus obtaining new examples of strongly shortcut groups. The proof relies on a result of independent interest: we show that every…

Group Theory · Mathematics 2023-10-24 Nima Hoda , Suraj Krishna M S

This paper examines a systematic method to construct a pair of (inter-related) root systems for arbitrary Coxeter groups from a class of non-standard geometric representations. This method can be employed to construct generalizations of…

Representation Theory · Mathematics 2013-03-18 Xiang Fu

The aim of this note is to show that every subset of a given topological space is the intersection of a preopen and a preclosed set, therefore $\beta$-locally closed, and that every topological space is $\beta$-submaximal.

General Topology · Mathematics 2007-05-23 Julian Dontchev , Maximilian Ganster

The aim of this work is to prove a conjecture related to the Combinatorial Invariance Conjecture of Kazhdan-Lusztig polynomials, in the parabolic setting, for lower intervals in every arbitrary Coxeter group. This result improves and…

Combinatorics · Mathematics 2018-07-09 Mario Marietti

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 prove that any standard parabolic subgroup of any Artin group is convex with respect to the standard generating set.

Group Theory · Mathematics 2017-05-04 Ruth Charney , Luis Paris

We show that the geometric realisation of the poset of proper parabolic subgroups of a large-type Artin group has a systolic geometry. We use this geometry to show that the set of parabolic subgroups of a large-type Artin group is stable…

Group Theory · Mathematics 2021-01-19 María Cumplido , Alexandre Martin , Nicolas Vaskou

We study classes of right-angled Coxeter groups with respect to the strong submodel relation of parabolic subgroup. We show that the class of all right-angled Coxeter group is not smooth, and establish some general combinatorial criteria…

Logic · Mathematics 2019-12-19 Tapani Hyttinen , Gianluca Paolini

In this paper, we study the decomposition of Bruhat intervals in a Coxeter group with respect to cosets of a parabolic subgroup. Our main result is that the intersection of a lower Bruhat interval with a parabolic coset contains a unique…

Combinatorics · Mathematics 2022-05-24 Suho Oh , Edward Richmond

In this paper, we show that the center of every Coxeter group is finite and isomorphic to $(\Z_2)^n$ for some $n\ge 0$. Moreover, for a Coxeter system $(W,S)$, we prove that $Z(W)=Z(W_{S\setminus\tilde{S}})$ and $Z(W_{\tilde{S}})=1$, where…

Group Theory · Mathematics 2007-05-23 Tetsuya Hosaka