English
Related papers

Related papers: Flat braid groups, right-angled Artin groups, and …

200 papers

We give formulae for the first homology of the $n$-braid group and the pure 2-braid group over a finite graph in terms of graph theoretic invariants. As immediate consequences, a graph is planar if and only if the first homology of the…

Geometric Topology · Mathematics 2015-03-17 Ki Hyoung Ko , Hyo Won Park

We prove that the conjugacy problem in right-angled Artin groups (RAAGs), as well as in a large and natural class of subgroups of RAAGs, can be solved in linear-time. This class of subgroups contains, for instance, all graph braid groups…

Group Theory · Mathematics 2008-02-14 John Crisp , Eddy Godelle , Bert Wiest

Let $M$ be the disk or a compact, connected surface without boundary different from the sphere $S^2$ and the real projective plane $\mathbb{R}P^2$, and let $N$ be a compact, connected surface (possibly with boundary). It is known that the…

Geometric Topology · Mathematics 2025-10-30 R. M. de A. Cruz

The rank of a hierarchically hyperbolic space is the maximal number of unbounded factors in a standard product region. For hierarchically hyperbolic groups, this coincides with the maximal dimension of a quasiflat. Examples for which the…

Geometric Topology · Mathematics 2020-08-25 Jason Behrstock , Mark F Hagen , Alessandro Sisto

A result of Allock [1](arXiv:math/9907194) states that certain orbifold braid groups contain Artin groups of type $D_n$, $\tilde{B}_n$ and $\tilde{D}_n$ as finite index subgroups. The underlying orbifolds have at most two cone points of…

Group Theory · Mathematics 2023-12-19 Jonas Flechsig

We compute the BNS-invariant for the pure symmetric automorphism groups of right-angled Artin groups. We use this calculation to show that the pure symmetric automorphism group of a right-angled Artin group is itself not a right-angled…

Group Theory · Mathematics 2013-11-12 Nic Koban , Adam Piggott

We show that graph products of finite abelian groups are elementarily equivalent if and only if they are $\exists\forall$-equivalent if and only if they are isomorphic. In particular, two right-angled Coxeter groups are elementarily…

Group Theory · Mathematics 2014-02-26 Montserrat Casals-Ruiz , Ilya Kazachkov , Vladimir Remeslennikov

We determine the factorial growth rate of the number of finite index subgroups of right-angled Artin groups as a function of the index. This turns out to depend solely on the independence number of the defining graph. We also make a…

Group Theory · Mathematics 2019-09-11 Hyungryul Baik , Bram Petri , Jean Raimbault

We show that the simple elements of the dual Garside structure of an Artin group of type $D_n$ are Mikado braids, giving a positive answer to a conjecture of Digne and the second author. To this end, we use an embedding of the Artin group…

Group Theory · Mathematics 2017-10-25 Barbara Baumeister , Thomas Gobet

We classify two-dimensional right-angled Coxeter groups that are quasiisometric to a right-angled Artin group defined by a tree, and show that when this is true the right-angled Coxeter group actually contains a visible finite index…

Group Theory · Mathematics 2025-11-12 Christopher H. Cashen

We consider braids on $m+n$ strands, such that the first $m$ strands are trivially fixed. We denote the set of all such braids by $B_{m,n}$. Via concatenation $B_{m,n}$ acquires a group structure. The objective of this paper is to find a…

Geometric Topology · Mathematics 2016-09-07 Sofia Lambropoulou

We prove similar theorems concerning the structure of bundles involving complements of fiber-type hyperplane arrangements and orbit configuration spaces. These results facilitate analysis of the fundamental groups of these spaces, which may…

Geometric Topology · Mathematics 2007-05-23 Daniel C. Cohen

For a finite simplicial graph $\Gamma$, let $A(\Gamma)$ denote the right-angled Artin group on $\Gamma$. Recently Kim and Koberda introduced the extension graph $\Gamma^e$ for $\Gamma$, and established the Extension Graph Theorem: for…

Geometric Topology · Mathematics 2018-07-03 Eon-Kyung Lee , Sang-Jin Lee

We prove some conditions for the existence of higher dimensional algebraic fibering of group extensions. This leads to various corollaries on incoherence of groups and some geometric examples of algebraic fibers of type $F_n$ but not…

Group Theory · Mathematics 2023-11-13 Dessislava H. Kochloukova , Stefano Vidussi

We study the large-scale geometry of graph braid groups $\mathbb{B}_n(\mathsf{\Gamma})$, viewed as the fundamental groups of discrete configuration spaces $UD_n(\mathsf{\Gamma})$, which are special cube complexes in the sense of…

Geometric Topology · Mathematics 2026-03-25 Byung Hee An , Sangrok Oh

Let $M$ be a compact surface without boundary, and $n\geq 2$. We analyse the quotient group $B_n(M)/\Gamma_2(P_n(M))$ of the surface braid group $B_{n}(M)$ by the commutator subgroup $\Gamma_2(P_n(M))$ of the pure braid group $P_{n}(M)$. If…

In \cite{Oh22}, the second author defined a complex of groups decomposition of the fundamental group of a finitely generated 2-dimensional special group, called an \emph{intersection complex}, which is a quasi-isometry invariant. In this…

Group Theory · Mathematics 2025-02-17 Byung Hee An , Sangrok Oh

In this article, we consider qualified notions of geometric finiteness in mapping class groups called parabolically geometrically finite (PGF) and reducibly geometrically finite (RGF). We examine several constructions of subgroups and…

Geometric Topology · Mathematics 2025-09-16 Tarik Aougab , Harrison Bray , Spencer Dowdall , Hannah Hoganson , Sara Maloni , Brandis Whitfield

A finite simple graph \G determines a right-angled Artin group G_\G, with one generator for each vertex v, and with one commutator relation vw=wv for each pair of vertices joined by an edge. The Bestvina-Brady group N_\G is the kernel of…

Algebraic Geometry · Mathematics 2007-12-04 Alexandru Dimca , Stefan Papadima , Alexander I. Suciu

We attach to every Coxeter system (W,S) an extension C_W of the corresponding Iwahori-Hecke algebra. We construct a 1-parameter family of (generically surjective) morphisms from the group algebra of the corresponding Artin group onto C_W.…

Representation Theory · Mathematics 2017-01-16 Ivan Marin