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Related papers: On Thompson Groups for Wa\.zewski Dendrites

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A remarkable result of Thompson states that a finite group is soluble if and only if its two-generated subgroups are soluble. This result has been generalized in numerous ways, and it is in the core of a wide area of research in the theory…

Group Theory · Mathematics 2019-08-12 P. Hauck , L. S. Kazarin , A. Martínez-Pastor , M. D. Pérez-Ramos

Recall that a group $G$ is said to be $\frac{3}{2}$-generated if every non-trivial element of $G$ belongs to a generating pair of $G$. Thompson's group $V$ was proved to be $\frac{3}{2}$-generated by Donoven and Harper in 2019. It was the…

Group Theory · Mathematics 2022-10-10 Gili Golan

This note serves as a short and reader-friendly introduction to twisted Brin-Thompson groups, which were recently constructed by Belk and the author to provide a family of simple groups with a variety of interesting properties. Most…

Group Theory · Mathematics 2022-01-04 Matthew C. B. Zaremsky

This article is dedicated to the study of asymptotically rigid mapping class groups of infinitely-punctured surfaces obtained by thickening planar trees. Such groups include the braided Ptolemy-Thompson groups $T^\sharp,T^\ast$ introduced…

Group Theory · Mathematics 2022-08-17 Anthony Genevois , Anne Lonjou , Christian Urech

It is shown that the restriction of the action of any group with finite orbit on the minimal sets of dendrites is equicontinuous. Consequently, we obtain that the action of any amenable group and Thompson group on dendrite restricted on…

Dynamical Systems · Mathematics 2019-04-15 el Houcein el Abdalaoui , Issam Naghmouchi

It is well known that every finite simple group has a generating pair. Moreover, Guralnick and Kantor proved that every finite simple group has the stronger property, known as $\frac{3}{2}$-generation, that every nontrivial element is…

Group Theory · Mathematics 2023-04-21 Scott Harper

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 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

We prove that Thompson's group F is not minimally almost convex with respect to any generating set which is a subset of the standard infinite generating set for F and which contains x_1. We use this to show that F is not almost convex with…

Group Theory · Mathematics 2021-09-24 Matthew Horak , Melanie Stein , Jennifer Taback

We investigate fixed-point properties of automorphisms of groups similar to R. Thompson's group $F$. Revisiting work of Gon\c{c}alves-Kochloukova, we deduce a cohomological criterion to detect infinite fixed-point sets in the…

We continue the study of projective Fra\"{i}ss\'{e} limits of trees initiated by Charatonik and Roe and we construct many generalized Wa\.{z}ewski dendrites as the topological realization of a projective Fra\"{i}ss\'{e} limit of families of…

Logic · Mathematics 2024-01-17 Alessandro Codenotti , Aleksandra Kwiatkowska

Given a finitely generated linear group $G$ over $\mathbb{Q}$, we construct a simple group $\Gamma$ that has the same finiteness properties as $G$ and admits $G$ as a quasi-retract. As an application, we construct a simple group of type…

Group Theory · Mathematics 2025-10-03 Claudio Llosa Isenrich , Eduard Schesler , Xiaolei Wu

We prove new results about the remarkable infinite simple groups introduced by Richard Thompson in the 1960s. We define the groups as partial transformation groups and we give a faithful representation in the Cuntz C*-algebra. For the…

Group Theory · Mathematics 2007-05-23 Jean-Camille Birget

Through the glasses of didactic reduction: We consider a (periodic) tessellation $\Delta$ of either Euclidean or hyperbolic $n$-space $M$. By a piecewise isometric rearrangement of $\Delta$ we mean the process of cutting $M$ along corank-1…

Group Theory · Mathematics 2021-10-13 Robert Bieri , Heike Sach

The authors classify the finite index subgroups of R. Thompson's group $F$. All such groups that are not isomorphic to $F$ are non-split extensions of finite cyclic groups by $F$. The classification describes precisely which finite index…

Group Theory · Mathematics 2007-11-08 Collin Bleak , Bronlyn Wassink

Hughes has defined a class of groups, which we call FSS (finite similarity structure) groups. Each FSS group acts on a compact ultrametric space by local similarities. The best-known example is Thompson's group V. Guided by previous work on…

Group Theory · Mathematics 2012-06-14 Daniel S. Farley , Bruce Hughes

A group is $\frac32$-generated if every non-trivial element is part of a generating pair. In 2019, Donoven and Harper showed that many Thompson groups are $\frac32$-generated and posed five questions. The first of these is whether there…

Group Theory · Mathematics 2021-12-03 Charles Garnet Cox

We prove a variety of results about the group von Neumann algebras associated to Thompson-like groups arising from so called $d$-ary cloning systems. Cloning systems are a framework developed by Witzel and the second author, with a $d$-ary…

Operator Algebras · Mathematics 2022-01-11 Eli Bashwinger , Matthew C. B. Zaremsky

Let $G$ be a finitely generated group, and let $\Sigma$ be a finite subset that generates $G$ as a monoid. The \emph{word problem of $G$ with respect to $\Sigma$} consists of all words in the free monoid $\Sigma^{\ast}$ that are equal to…

Group Theory · Mathematics 2014-12-04 Rose Berns-Zieve , Dana Fry , Johnny Gillings , Hannah Hoganson , Heather Mathews

The purpose of this paper is to study the properties of the irrational-slope Thompson's group $F_\tau$ introduced by Cleary in 1995. We construct presentations, both finite and infinite and we describe its combinatorial structure using…

Group Theory · Mathematics 2021-03-04 José Burillo , Brita Nucinkis , Lawrence Reeves