English
Related papers

Related papers: The conjugacy problem for Thompson-like groups

200 papers

We investigate the relationship between endomorphisms of the Cuntz algebra ${\mathcal O}_2$ and endomorphisms of the Thompson groups $F$, $T$ and $V$ represented inside the unitary group of ${\mathcal O}_2$. For an endomorphism $\lambda_u$…

Operator Algebras · Mathematics 2017-10-24 Selçuk Barlak , Jeong Hee Hong , Wojciech Szymanski

This paper is dedicated to the conjugacy problem in $GL(n,\Z)$ and its connection with algebraic number theory. This connection may be summed up in the Latimer-MacDuffee-Taussky Theorem, which, in a very broad sense, identifies the…

Number Theory · Mathematics 2016-11-18 Lennard F Bakker , Pedro Martins Rodrigues , Miguel M. R. Moreira

We study conjugacy classes of solutions to systems of equations and inequations over torsion-free hyperbolic groups, and describe an algorithm to recognize whether or not there are finitely many conjugacy classes of solutions to such a…

Group Theory · Mathematics 2014-02-26 Daniel Groves , Henry Wilton

We prove that Thompson's group $T$ and, more generally, all the Higman-Thompson groups $T_n$ have quadratic Dehn function.

Group Theory · Mathematics 2025-07-11 Matteo Migliorini

We give a reduction of the conjugacy problem among outer automorphisms of free (and torsion-free hyperbolic) groups to specific algorithmic problems pertaining to mapping tori of polynomially growing automorphisms. We explain how to use…

Group Theory · Mathematics 2025-10-03 François Dahmani , Nicholas Touikan

In his papers [2], [3] Brin introduced the higher dimensional Thompson groups nV which are generalizations to the Thompson's group V of self-homeomorphisms of the Cantor set and found a finite set of generators and relations in the case n =…

Group Theory · Mathematics 2011-05-19 Johanna Hennig , Francesco Matucci

Dehn fillings for relatively hyperbolic groups generalize the topological Dehn surgery on a non-compact hyperbolic $3$-manifold such as a hyperbolic knot complement. We prove a rigidity result saying that if two non-elementary relatively…

Group Theory · Mathematics 2018-11-14 François Dahmani , Vincent Guirardel

We study quasimorphisms and bounded cohomology of a variety of braided versions of Thompson groups. Our first main result is that the Brin--Dehornoy braided Thompson group $bV$ has an infinite-dimensional space of quasimorphisms and thus…

Group Theory · Mathematics 2024-07-10 Francesco Fournier-Facio , Yash Lodha , Matthew C. B. Zaremsky

We give a solution to Dehn's isomorphism problem for the class of all hyperbolic groups, possibly with torsion. We also prove a relative version for groups with peripheral structures. As a corollary, we give a uniform solution to…

Group Theory · Mathematics 2021-04-02 François Dahmani , Vincent Guirardel

We compare three approaches to the notion of conjugacy for semigroups, the first one via the transitive closure of the $uv\sim vu$ relation, the second one via an action of inverse semigroups on themselves by partial transformations, and…

Group Theory · Mathematics 2010-04-02 Ganna Kudryavtseva , Volodymyr Mazorchuk

We study the isometry group of a globally hyperbolic spatially compact Lorentz surface. Such a group acts on the circle, and we show that when the isometry group acts non properly, the subgroups of $\mathrm{Diff}(\mathbb{S}^1)$ obtained are…

Differential Geometry · Mathematics 2014-05-28 Daniel Monclair

The goal of this paper is to construct quasi-isometrically embedded subgroups of Thompson's group $F$ which are isomorphic to $\fz^n$ for all $n$. A result estimating the norm of an element of Thompson's group is found. As a corollary,…

Group Theory · Mathematics 2007-05-23 Jose Burillo

We prove that Thompson's group $F$ has a subgroup $H$ such that the conjugacy problem in $H$ is undecidable and the membership problem in $H$ is easily decidable. The subgroup $H$ of $F$ is a closed subgroup of $F$. That is, every function…

Group Theory · Mathematics 2021-05-04 Gili Golan , Mark Sapir

The Thompson-Higman groups G_{k,i} have a natural generalization to monoids M_{k,i}, and inverse monoids Inv_{k,i}. We study some structural features of M_{k,i} and Inv_{k,i} and investigate the computational complexity of decision…

Group Theory · Mathematics 2009-04-17 Jean-Camille Birget

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

Thompson's group $V$ has a rich variety of subgroups, containing all finite groups, all finitely generated free groups and all finitely generated abelian groups, the finitary permutation group of a countable set, as well as many wreath…

Group Theory · Mathematics 2020-09-29 José Burillo , Sean Cleary , Claas E. Röver

We generalize the Brin-Higman-Thompson groups $n G_{k,1}$ to monoids $n M_{k,1}$, for $n \ge 1$ and $k \ge 2$, by replacing bijections by partial functions. The monoid $n M_{k,1}$ has $n G_{k,1}$ as its group of units, and is…

Group Theory · Mathematics 2020-06-30 J. C. Birget

Let $G$ be a linear algebraic group over an algebraically closed field of characteristic $p\geq 0$. We show that if $H_1$ and $H_2$ are connected subgroups of $G$ such that $H_1$ and $H_2$ have a common maximal unipotent subgroup and…

Group Theory · Mathematics 2018-01-03 Daniel Lond , Benjamin Martin

This paper studies when a pair of elements in F are the images of the standard generators of F under a self monomorphism.

Group Theory · Mathematics 2009-12-04 Bronlyn Wassink

We look at the automorphisms of Thompson type groups of piecewise linear homeomorphisms of the real line or circle that use slopes that are integral powers of a fixed integer n with n>2. We show that large numbers of "exotic" automorphisms…

Group Theory · Mathematics 2013-09-04 Matthew G. Brin , Fernando Guzman