English
Related papers

Related papers: Braided Thompson groups with and without quasimorp…

200 papers

The braided Thompson group $\mathcal B$ is an asymptotic mapping class group of a sphere punctured along the standard Cantor set, endowed with a rigid structure. Inspired from the case of finite type surfaces we consider a Hatcher-Thurston…

Geometric Topology · Mathematics 2019-01-25 Louis Funar , Maxime Nguyen

We construct a family of infinite simple groups that we call \emph{twisted Brin-Thompson groups}, generalizing Brin's higher-dimensional Thompson groups $sV$ ($s\in\mathbb{N}$). We use twisted Brin-Thompson groups to prove a variety of…

Group Theory · Mathematics 2022-08-17 James Belk , Matthew C. B. Zaremsky

We describe pure braided versions of Thompson's group F. These groups, $BF$ and $\hat{BF}$, are subgroups of the braided versions of Thompson's group V, introduced by Brin and Dehornoy. Unlike V, elements of F are order-preserving self-maps…

Group Theory · Mathematics 2018-03-19 Thomas Brady , Jose Burillo , Sean Cleary , Melanie Stein

We consider Thompson's groups from the perspective of mapping class groups of surfaces of infinite type. This point of view leads us to the braided Thompson groups, which are extensions of Thompson's groups by infinite (spherical) braid…

Group Theory · Mathematics 2013-10-25 Louis Funar , Christophe Kapoudjian , Vlad Sergiescu

We present a generalization of the Dehornoy-Brin braided Thompson group $BV_2$ that uses recursive braids. Our new groups are denoted by $BV_{n,r}(H)$, for all $n\geq 2,r\geq 1$ and $H \leq \mathcal{B}_n$, where $\mathcal{B}_n$ is the braid…

Group Theory · Mathematics 2020-07-31 Julio Aroca , María Cumplido

The main result of this article is that any braided (resp. annular, planar) diagram group $D$ splits as a short exact sequence $1 \to R \to D \to S \to 1$ where $R$ is a subgroup of some right-angled Artin group and $S$ a subgroup of…

Group Theory · Mathematics 2019-08-26 Anthony Genevois

Motivated by Burillo, Cleary and Roever's summary on obstructions of subgroups of Thompson's group $V,$ we explored the higher dimensional version of the groups, Brin-Thompson groups $nV$ and $SV,$ a class of infinite dimensional…

Group Theory · Mathematics 2025-04-03 Xiaobing Sheng

Matthew Brin and Patrick Dehornoy independently discovered a braided version BV of Thompson's group V. In this paper, we discuss some properties of BV that might make the group interesting for group based cryptography. In particular, we…

Group Theory · Mathematics 2008-07-02 Kai-Uwe Bux , Dmitriy Sonkin

Hughes defined a class of groups that act as local similarities on compact ultrametric spaces. Guba and Sapir had previously defined braided diagram groups over semigroup presentations. The two classes of groups share some common…

Group Theory · Mathematics 2014-06-19 Daniel Farley , Bruce Hughes

We study the bounded cohomology of certain groups acting on the Cantor set. More specifically, we consider the full group of homeomorphisms of the Cantor set as well as Thompson's group $V$. We prove that both of these groups are boundedly…

Group Theory · Mathematics 2022-10-04 Konstantin Andritsch

We show that the \s{\phi}-labeled Thompson groups and the twisted Brin--Thompson groups are boundedly acyclic. This allows us to prove several new embedding results for groups. First, every group of type $F_n$ embeds quasi-isometrically…

Group Theory · Mathematics 2025-04-15 Fan Wu , Xiaolei Wu , Mengfei Zhao , Zixiang Zhou

In previous work, joint with Bux, Fluch, Marschler and Witzel, we proved that the braided Thompson groups are of type $\textrm{F}_\infty$. The proof utilized certain contractible cube complexes, which in this paper we prove are CAT(0). We…

Group Theory · Mathematics 2021-04-13 Matthew C. B. Zaremsky

We construct braided versions $sV_{br}$ of the Brin-Thompson groups $sV$ and prove that they are of type $F_\infty$. The proof involves showing that the matching complexes of colored arcs on surfaces are highly connected.

Group Theory · Mathematics 2021-01-12 Robert Spahn

Braided Thompson's groups are finitely presented groups introduced by Brin and Dehornoy which contain the ordinary braid groups $B_n$, the finitary braid group $B_{\infty}$ and Thompson's group $F$ as subgroups. We describe some of the…

Group Theory · Mathematics 2018-03-19 José Burillo , Sean Cleary

We study a class of generalisations of Thompson's group $V$ arising naturally as topological full groups of purely infinite, minimal groupoids. In the process, we show that the derived subgroup of such a group is 2-generated whenever it is…

Group Theory · Mathematics 2024-04-29 Eusebio Gardella , Owen Tanner

The groups QF, QT, and QV are groups of quasi-automorphisms of the infinite binary tree. Their names indicate a similarity with Thompson's well-known groups F, T, and V. We will use the theory of diagram groups over semigroup presentations…

Group Theory · Mathematics 2018-05-02 Samuel Audino , Delaney R. Aydel , Daniel S. Farley

Pursueing our investigations on the relations between Thompson groups and mapping class groups, we introduce the group $T^*$ (and its further generalizations) which is an extension of the Ptolemy-Thompson group $T$ by means of the full…

Geometric Topology · Mathematics 2014-11-11 Louis Funar , Christophe Kapoudjian

We introduce a refinement of bounded cohomology and prove that the suitable comparison homomorphisms vanish for an amenable group. We investigate in this context Thompson's group F and provide further evidence towards its amenability. We…

Group Theory · Mathematics 2025-12-23 Światosław R. Gal , Jarek Kędra

We prove that the Brin-Thompson groups sV, also called higher dimensional Thompson's groups, are of type F_\infty for all natural numbers s. This result was previously shown for s up to 3, by considering the action of sV on a naturally…

Group Theory · Mathematics 2014-03-19 Martin Fluch , Marco Marschler , Stefan Witzel , Matthew C. B. Zaremsky

We show that pure subgroups of infinitely braided Thompson's are bi-orderable. For every finitely generated pure subgroup, we give explicit sets of generators.

Group Theory · Mathematics 2023-12-18 María Cumplido
‹ Prev 1 2 3 10 Next ›