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Related papers: Geometric presentations for Thompson's groups

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We construct a "higher dimensional" version 2V of Thompson's group V. Like V it is an infinite, finitely presented, simple subgroup of the homeomorphism group of the Cantor set, but we show that it is not isomorphic to V by showing that the…

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

If $\phi$ is an automorphism of a group $G$ and $x,y\in G$, we say that $x$ and $y$ are $\phi$-twisted conjugates if there exists an $z\in G$ such that $y=z.x.\phi(z^{-1})$. This is an equivalence relation. If there are infinitely many…

Group Theory · Mathematics 2014-01-20 Daciberg Goncalves , Parameswaran Sankaran

We prove a variety of results about subgroups of Thompson's group $V$. First we prove that every action graph of a finitely generated subgroup of $V$ acting on an orbit in Cantor space is quasi-isometric to a tree. Then we prove that for a…

Group Theory · Mathematics 2026-05-21 James Hyde , Rachel Skipper , Matthew C. B. Zaremsky

A machine developed by the second author produces a rich family of unitary representations of the Thompson groups F,T and V. We use it to give direct proofs of two previously known results. First, we exhibit a unitary representation of V…

Group Theory · Mathematics 2018-05-08 Arnaud Brothier , Vaughan F. R. Jones

We construct the first examples of finitely presented simple groups of orientation-preserving homeomorphisms of the real line. Our examples are also of type $F_{\infty}$, have infinite geometric dimension, and admit a nontrivial homogeneous…

Group Theory · Mathematics 2023-12-27 James Hyde , Yash Lodha

We show that each of Thompson's groups F, T, and V have infinitely many ends relative to certain subgroups. We go on to show that T and V both have Serre's property FA, i.e., any action of T or V on a tree will have a fixed point. (The…

Group Theory · Mathematics 2007-08-13 Daniel Farley

We define and investigate a geometric object, called an associative geometry, corresponding to an associative algebra (and, more generally, to an associative pair). Associative geometries combine aspects of Lie groups and of generalized…

Rings and Algebras · Mathematics 2010-05-19 Wolfgang Bertram , Michael Kinyon

We define and investigate a geometric object, called an associative geometry, corresponding to an associative algebra (and, more generally, to an associative pair). Associative geometries combine aspects of Lie groups and of generalized…

Rings and Algebras · Mathematics 2010-05-31 Wolfgang Bertram , Michael Kinyon

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 construct a family of groups from suitable higher rank graphs which are analogues of the finite symmetric groups. We introduce homological invariants showing that many of our groups are, for example, not isomorphic to $nV$, when $n \geq…

Group Theory · Mathematics 2023-02-28 Mark V Lawson , Aidan Sims , Alina Vdovina

Presentations are computed for a braided version BV of Thompson's group V and for V itself showing that there is an Artin group/Coxeter group relation between them. The presentation for V is obtained from that for BV by declaring all that…

Group Theory · Mathematics 2013-08-08 Matthew G. Brin

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

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

We provide a new characterization of amenability for countable groups, based on frame representations admitting almost invariant vectors. By relaxing the frame inequalities, thereby weakening amenability, we obtain a large class of…

Group Theory · Mathematics 2025-12-03 Dorin Ervin Dutkay , Catalin Georgescu , Gabriel Picioroaga

We prove that a permutation group in which different finite sets have different stabilizers cannot satisfy any group law. For locally compact topological groups with this property we show that almost all finite subsets of the group generate…

Group Theory · Mathematics 2007-05-23 Miklos Abert

In the quest in constructing conformal field theories (CFT) Jones has discovered a beautiful and deep connection between CFT, Richard Thompson's groups and knot theory. This led to a powerful functorial framework for constructing actions of…

Group Theory · Mathematics 2021-12-03 Arnaud Brothier

We prove that the braided Thompson's groups $V_{\rm br}$ and $F_{\rm br}$ are of type $F_\infty$, confirming a conjecture by John Meier. The proof involves showing that matching complexes of arcs on surfaces are highly connected. In an…

Group Theory · Mathematics 2021-06-23 Kai-Uwe Bux , Martin Fluch , Marco Marschler , Stefan Witzel , Matthew C. B. Zaremsky

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 a recent paper, we showed that groups admitting "veelike actions" on a finite language embed in mapping class groups of certain two-sided subshifts. In this note, we illustrate this theorem for the embedding of Thompson's $V$ by…

Group Theory · Mathematics 2021-04-07 Ville Salo

In this paper, we compute the {\Sigma}^n(G) and {\Omega}^n(G) invariants when 1 \rightarrow H \rightarrow G \rightarrow K \rightarrow 1 is a short exact sequence of finitely generated groups with K finite. We also give sufficient conditions…

Group Theory · Mathematics 2012-06-11 Nic Koban , Peter Wong