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Related papers: Algebraic invariants for Bestvina-Brady groups

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The virtual singular braid group arises as a natural common generalization of classical singular braid groups and virtual braid groups. In this paper, we study several algebraic properties of the virtual singular braid group $VSG_n$. We…

Group Theory · Mathematics 2026-04-10 Oscar Ocampo

From a group $H$ and a non-trivial element $h$ of $H$, we define a representation $\rho: B_n \to \Aut(G)$, where $B_n$ denotes the braid group on $n$ strands, and $G$ denotes the free product of $n$ copies of $H$. Such a representation…

Group Theory · Mathematics 2007-05-23 John Crisp , Luis Paris

We prove that every right-angled Artin group occurs as a finite-index subgroup of the outer automorphism group of another right-angled Artin group. We furthermore show that the latter group can be chosen in such a way that the quotient is…

Group Theory · Mathematics 2024-03-14 Manuel Wiedmer

The f-invariant is an injective homomorphism from the 2-line of the Adams-Novikov spectral sequence to a group which is closely related to divided congruences of elliptic modular forms. We compute the f-invariant for two infinite families…

Algebraic Topology · Mathematics 2007-05-23 Jens Hornbostel , Niko Naumann

We initiate the study of C*-algebras and groupoids arising from left regular representations of Garside categories, a notion which originated from the study of Braid groups. Every higher rank graph is a Garside category in a natural way. We…

Operator Algebras · Mathematics 2022-05-03 Xin Li

We consider $\Sigma$-invariants of Artin groups that satisfy the $K(\pi,1)$-conjecture. These invariants determine the cohomological finiteness conditions of subgroups that contain the derived subgroup. We extend a known result for even…

Group Theory · Mathematics 2024-02-21 Marcos Escartín Ferrer , Conchita Martínez Pérez

The present work is concerned with characterizing some algebraic invariants of edge ideals of hypergraphs. To this aim, firstly, we introduce some kinds of combinatorial invariants similar to matching numbers for hypergraphs. Then we…

Commutative Algebra · Mathematics 2025-06-10 Somayeh Moradi , Fahimeh Khosh-Ahang Ghasr

We provide an explicit construction that allows one to easily decompose a graph braid group as a graph of groups. This allows us to compute the braid groups of a wide range of graphs, as well as providing two general criteria for a graph…

Group Theory · Mathematics 2023-09-15 Daniel Berlyne

In this paper we study topological invariants of a class of random groups. Namely, we study right angled Artin groups associated to random graphs and investigate their Betti numbers, cohomological dimension and topological complexity. The…

Algebraic Topology · Mathematics 2011-01-11 Armindo Costa , Michael Farber

In arXiv:0910.1727 we find certain finite homomorphic images of Artin braid group into appropriate symmetric groups, which a posteriori are extensions of the symmetric group on n letters by an abelian group. The main theorem of this paper…

Group Theory · Mathematics 2010-04-19 Valentin Vankov Iliev

For each subcomplex of the standard CW-structure on any torus, we compute the homology of a certain infinite cyclic regular covering space. In all cases when the homology is finitely generated, we also compute the cohomology ring. For…

Algebraic Topology · Mathematics 2007-12-03 Ian J Leary , Muge Saadetoglu

We solve the isomorphism problem for braid groups on trees with $n = 4$ or 5 strands. We do so in three main steps, each of which is interesting in its own right. First, we establish some tools and terminology for dealing with computations…

Group Theory · Mathematics 2010-04-05 Lucas Sabalka

We show that the class of large-type Artin groups is invariant under isomorphism, in stark contrast with the corresponding situation for Coxeter groups. We obtain this result by providing a purely algebraic characterisation of large-type…

Group Theory · Mathematics 2023-05-11 Alexandre Martin , Nicolas Vaskou

We reduce the $K(\pi,1)$-conjecture for all Artin groups to properties of Artin groups whose Coxeter diagrams are trees, from which we deduce new classes of Artin groups satisfying the $K(\pi,1)$-conjecture. This relies on constructing…

Group Theory · Mathematics 2026-02-23 Jingyin Huang

In this note, we characterise when the kernel of a rational character of a right-anlged Artin group, also known as generalised Bestiva-Brady group, is finitely generated and finitely presented. In these cases, we exhibit a finite generating…

Group Theory · Mathematics 2024-09-11 Montserrat Casals-Ruiz , Ilya Kazachkov , Mallika Roy

The braid group $B_{n}$, endowed with Artin's presentation, admits two distinguished involutions. One is the anti-automorphism ${\rm{rev}}: B_{n} \to B_{n}$, $v \mapsto \bar{v}$, defined by reading braids in the reverse order (from right to…

Geometric Topology · Mathematics 2007-05-23 Florian Deloup

We give a necessary and sufficient condition for a graph to have a right-angled Artin group as its braid group for braid index $\ge 5$. In order to have the necessity part, graphs are organized into small classes so that one of homological…

Geometric Topology · Mathematics 2010-06-24 Jee Hyoun Kim , Ki Hyoung Ko , Hyo Won Park

It has long been known that the combinatorial properties of a graph $\Gamma$ are closely related to the group theoretic properties of its right angled artin group (raag). It's natural to ask if the graph homomorphisms are similarly related…

Group Theory · Mathematics 2025-09-24 Chris Grossack

We reduce a strong version of the twist conjecture for Artin groups to Artin groups whose defining graphs have no separating vertices. This produces new examples of Artin groups satisfying the conjecture, and sheds more light on the…

Group Theory · Mathematics 2026-05-13 Oli Jones , Giorgio Mangioni , Giovanni Sartori

We report on results about a study of algebraic graph invariants, based on computer exploration, and motivated by graph-isomorphism and reconstruction problems.

Combinatorics · Mathematics 2008-12-17 Pouzet Maurice , Nicolas M. Thiéry