English
Related papers

Related papers: Reflection factorizations and quasi-Coxeter elemen…

200 papers

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 show that for a parabolic quasi-Coxeter element in an affine Coxeter group the Hurwitz action on its set of reduced factorizations into a product of reflections is transitive. We call an element of the Coxeter group parabolic…

Group Theory · Mathematics 2019-09-27 Patrick Wegener

We extend a result of Lewis and Reiner from finite Coxeter groups to all Coxeter groups by showing that two reflection factorizations of a Coxeter element lie in the same Hurwitz orbit if and only if they share the same multiset of…

Combinatorics · Mathematics 2019-01-18 Patrick Wegener , Sophiane Yahiatene

We show that in the complex reflection group $G_6$, reflection factorizations of a Coxeter element that have the same length and multiset of conjugacy classes are in the same Hurwitz orbit. This confirms one case of a conjecture of Lewis…

Combinatorics · Mathematics 2022-02-07 Gaurav Gawankar , Dounia Lazreq , Mehr Rai , Seth Sabar

We enumerate Hurwitz orbits of shortest reflection factorizations of an arbitrary element in the infinite family $G(m, p, n)$ of complex reflection groups. As a consequence, we characterize the elements for which the action is transitive…

Combinatorics · Mathematics 2022-06-17 Joel Brewster Lewis , Jiayuan Wang

We define parabolic quasi-Coxeter elements in well generated complex reflection groups. We characterize them in multiple natural ways, and we study two combinatorial objects associated with them: the collections $\operatorname{Red}_W(g)$ of…

Combinatorics · Mathematics 2024-01-01 Theo Douvropoulos , Joel Brewster Lewis , Alejandro H. Morales

In a finite real reflection group, two factorizations of a Coxeter element into an arbitrary number of reflections are shown to lie in the same orbit under the Hurwitz action if and only if they use the same multiset of conjugacy classes.…

Combinatorics · Mathematics 2016-12-12 Joel Brewster Lewis , Victor Reiner

We prove that the Hurwitz action on reflection factorizations of Coxeter elements is transitive up to certain natural constraints in the complex reflection groups G4 and G5. This affirms a more general conjecture by Lewis and Reiner in…

Combinatorics · Mathematics 2018-08-06 Zachery Peterson

We provide a necessary and sufficient condition on an element of a finite Coxeter group to ensure the transitivity of the Hurwitz action on its set of reduced decompositions into products of reflections. We show that this action is…

Group Theory · Mathematics 2015-12-16 Barbara Baumeister , Thomas Gobet , Kieran Roberts , Patrick Wegener

We show that the Hurwitz action is "as transitive as possible" on reflection factorizations of Coxeter elements in the well-generated complex reflection groups $G(d, 1, n)$ (the group of $d$-colored permutations) and $G(d, d, n)$.

Combinatorics · Mathematics 2020-06-29 Joel Brewster Lewis

We study the Hurwitz action of the classical braid group on factorisations of a Coxeter element c in a well-generated complex reflection group W. It is well-known that the Hurwitz action is transitive on the set of reduced decompositions of…

Group Theory · Mathematics 2010-01-27 Vivien Ripoll

We give uniform formulas for the number of full reflection factorizations of a parabolic quasi-Coxeter element in a Weyl group or complex reflection group, generalizing the formula for the genus-0 Hurwitz numbers. This paper is the…

Combinatorics · Mathematics 2025-05-20 Theo Douvropoulos , Joel Brewster Lewis , Alejandro H. Morales

In this note, we provide a short and self-contained proof that the braid group on n strands acts transitively on the set of reduced factorizations of a Coxeter element in a Coxeter group of finite rank n into products of reflections. We…

Group Theory · Mathematics 2014-02-12 Barbara Baumeister , Matthew Dyer , Christian Stump , Patrick Wegener

We consider the Hurwitz action on quasipositive factorizations of a 3-braid. In a previous paper, for any given 3-braid we described a certain finite set which contains at least one representative of each orbit. Here we give an algorithm to…

Group Theory · Mathematics 2024-12-04 Stepan Yu. Orevkov

We prove that two reflection factorizations of a given element in an exceptional rank-2 complex reflection group of tetrahedral type are Hurwitz-equivalent if and only if they generate the same subgroup and have the same multiset of…

Combinatorics · Mathematics 2021-10-19 Tyler Minnick , Colin Pirillo , Sarah Racile , Yueqi Wang

We prove universal (case-free) formulas for the weighted enumeration of factorizations of Coxeter elements into products of reflections valid in any well-generated reflection group $W$, in terms of the spectrum of an associated operator,…

Combinatorics · Mathematics 2023-06-14 Guillaume Chapuy , Theo Douvropoulos

We provide a variety of cases in which two factorizations have Hurwitz orbits of the same size. We begin with prototypical results about factorizations of length two, and show that cycling elements or flipping and inverting elements in any…

Combinatorics · Mathematics 2022-09-05 Colin Pirillo , Seth Sabar

We enumerate factorizations of a Coxeter element in a well generated complex reflection group into arbitrary factors, keeping track of the fixed space dimension of each factor. In the infinite families of generalized permutations, our…

Combinatorics · Mathematics 2024-02-07 Joel Brewster Lewis , Alejandro H. Morales

In this paper, we count factorizations of Coxeter elements in well-generated complex reflection groups into products of reflections. We obtain a simple product formula for the exponential generating function of such factorizations, which is…

Combinatorics · Mathematics 2015-06-12 Guillaume Chapuy , Christian Stump

We consider the Hurwitz action on quasipositive factorizations of 3-braids. We prove that every orbit contains an element of a special form. This fact provides an algorithm of finding representatives of every orbit for a given braid. We…

Group Theory · Mathematics 2024-12-03 Stepan Yu. Orevkov
‹ Prev 1 2 3 10 Next ›