English
Related papers

Related papers: New Presentations of Thompson's Groups and Applica…

200 papers

In this paper, it is shown that the reduced $\ell^p$-cohomology is trivial for a class of finitely generated amenable groups called transport amenable. These groups are those for which there exist a sequence of measures $\xi_n$ converging…

Group Theory · Mathematics 2013-04-15 Antoine Gournay

The purpose of this article is to formulate conjectural generalizations of Hindman's Theorem and Ellis's Lemma for nonassociative binary systems and relate them to the amenability problem for Thompson's group $F$. Partial results are…

Combinatorics · Mathematics 2018-07-18 Justin Tatch Moore

In 1968, John Thompson proved that a finite group $G$ is solvable if and only if every $2$-generator subgroup of $G$ is solvable. In this paper, we prove that solvability of a finite group $G$ is guaranteed by a seemingly weaker condition:…

Group Theory · Mathematics 2010-08-02 Silvio Dolfi , Marcel Herzog , Cheryl E. Praeger

In these notes we will survey recent results on various finitary approximation properties of infinite groups. We will discuss various restrictions on groups that are approximated for example by finite solvable groups or finite-dimensional…

Group Theory · Mathematics 2017-12-06 Andreas Thom

We study topological full groups attached to groupoid models for left regular representations of Garside categories. Groups arising in this way include Thompson's group $V$ and many of its variations such as R\"over-Nekrashevych groups. Our…

Operator Algebras · Mathematics 2024-10-15 Xin Li

In this note we show that the members of a certain class of local similarity groups are l2-invisible, i.e. the non-reduced group homology of the regular unitary representation vanishes in all degrees. This class contains for example…

Algebraic Topology · Mathematics 2019-02-20 Roman Sauer , Werner Thumann

It is not known whether Thompson's group F is automatic. With the recent extensions of the notion of an automatic group to graph automatic by Kharlampovich, Khoussainov and Miasnikov and then to C-graph automatic by the authors, a…

Group Theory · Mathematics 2015-01-21 Murray Elder , Jennifer Taback

We prove the following three closely related results. The first is that every finite simple group has a profinite presentation with 2 generators and at most 18 relations. The second is that if G is a finite simple group, F a field and M an…

Group Theory · Mathematics 2007-11-20 Robert Guralnick , William M. Kantor , Martin Kassabov , Alex Lubotzky

We provide the first example of a finitely presented (in fact, type $F_\infty$) group with elements whose stable commutator length is algebraic and irrational, answering a question of Calegari. Our example is the lift to the real line of…

Group Theory · Mathematics 2021-11-17 Francesco Fournier-Facio , Yash Lodha

We prove that every countable left-ordered group embeds into a finitely generated left-ordered simple group. Moreover, if the first group has a computable left-order, then the simple group also has a computable left-order. We also obtain a…

Group Theory · Mathematics 2022-03-09 Arman Darbinyan , Markus Steenbock

We introduce a new approach to representation theory of finite groups that uses some basic algebraic geometry and allows to do all the theory without using characters. With this approach, to any finite group $G$ we associate a finite number…

Representation Theory · Mathematics 2024-11-05 Enrique Arrondo

In this note, we compute the {\Sigma}^1(G) invariant when 1 {\to} H {\to} G {\to} K {\to} 1 is a short exact sequence of finitely generated groups with K finite. As an application, we construct a group F semidirect Z_2 where F is the R.…

Group Theory · Mathematics 2011-12-22 Nic Koban , Peter Wong

We give an analog of Frobenius' theorem about the factorization of the group determinant on the group algebra of finite abelian groups and we extend it into dihedral groups and generalized quaternion groups. Furthermore, we describe the…

Representation Theory · Mathematics 2014-05-09 N. Yamaguchi

We describe a generalization of the concept of a pc presentation that applies to groups with a nontrivial solvable radical. Such a representation can be much more efficient in terms of memory use and even of arithmetic, than permuattion and…

Group Theory · Mathematics 2025-09-25 Alexander Hulpke

We consider Turing machines as actions over configurations in $\Sigma^{\mathbb{Z}^d}$ which only change them locally around a marked position that can move and carry a particular state. In this setting we study the monoid of Turing machines…

Group Theory · Mathematics 2019-04-26 Sebastián Barbieri , Jarkko Kari , Ville Salo

We observe that the determinant of the representation provides a little restriction for the structure of the graded quotients $\mathcal{G}_k^Q{F}$ introduced in both [Algebr. Geom. Topol. 1 (2001) 39-55] and [J. Knot Theory Ramifications 13…

Geometric Topology · Mathematics 2010-04-20 Yasushi Kasahara

We show that the abstract commensurator of Thompson's group F is composed of four building blocks: two isomorphism types of simple groups, the multiplicative group of the positive rationals and a cyclic group of order two. The main result…

Group Theory · Mathematics 2014-11-11 José Burillo , Sean Cleary , Claas E. Röver

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

We introduce forest diagrams to represent elements of Thompson's group F. These diagrams relate to a certain action of F on the real line in the same way that tree diagrams relate to the standard action of F on the unit interval. Using…

Group Theory · Mathematics 2018-10-30 James M. Belk , Kenneth S. Brown

To any family of languages LAN, let us associate the class, denoted $\pi(\text{LAN})$, of finitely generated groups that admit a group presentation whose set of relators forms a language in LAN. We show that the class of L-presented groups,…

Group Theory · Mathematics 2025-08-26 Laurent Bartholdi , Leon Pernak , Emmanuel Rauzy