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Related papers: Geometric presentations for Thompson's groups

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We study the properties of groups that have presentations in which the square of each generator gives the identity and all relations are of even length. We consider the parabolic subgroups of such a group and show that every element has a…

Group Theory · Mathematics 2021-07-23 Isobel Webster

We give a new technique for constructing presentations by generators and relations for representations of groups like $SL_n(\mathbb{Z})$ and $Sp_{2g}(\mathbb{Z})$. Our results play an important role in recent work of the authors calculating…

Representation Theory · Mathematics 2025-04-02 Daniel Minahan , Andrew Putman

We give several new positive finite presentations for the pure braid group that are easy to remember and simple in form. All of our presentations involve a metric on the punctured disc so that the punctures are arranged "convexly", which is…

Geometric Topology · Mathematics 2007-05-23 Dan Margalit , Jon McCammond

In this paper we show that the cloning system construction of Skipper and Zaremsky [SZ21], under sufficient conditions, gives rise to Thompson-Like groups which are stable; in particular, these are McDuff groups in the sense of Deprez and…

Operator Algebras · Mathematics 2024-10-04 Rolando de Santiago , Patrick DeBonis , Krishnendu Khan

We show the irreducibility of some unitary representations of the group of symplectomorphisms and the group of contactomorphisms.

Representation Theory · Mathematics 2014-04-17 Łukasz Garncarek

Let $F$ be a global field. Let $G$ be a non trivial finite \'etale tame $F$-group scheme. We define height functions on the set of $G$-torsors over $F,$ which generalize the usual heights such as discriminant. As an analogue of the Malle…

Number Theory · Mathematics 2024-02-27 Ratko Darda , Takehiko Yasuda

In this paper, using some properties of fundamental groups and covering spaces of connected polyhedra and CW-complexes, we present topological proof for some famous theorems about finitely presented groups.

Algebraic Topology · Mathematics 2010-12-09 Behrooz Mashayekhy , Hanieh Mirebrahimi

We introduce the Pythagorean C*-algebras and use the category/functor method to construct unitary representations of Thompson's groups from representations of them. We calculate several examples.

Group Theory · Mathematics 2018-07-18 Arnaud Brothier , Vaughan F. R. Jones

We develop a theory of equivariant group presentations and relate them to the second homology group of a group. Our main application says that the second homology group of the Torelli subgroup of the mapping class group is finitely…

Geometric Topology · Mathematics 2020-06-09 Martin Kassabov , Andrew Putman

We show that Thompson's group F does not satisfy Cannon's almost convexity condition AC(n) for any integer n in the standard finite two generator presentation. To accomplish this, we construct a family of pairs of elements at distance n…

Group Theory · Mathematics 2018-03-19 Sean Cleary , Jennifer Taback

We show that representations of the Thompson group $F$ in the automorphisms of a noncommutative probability space yield a large class of bilateral stationary noncommutative Markov processes. As a partial converse, bilateral stationary…

Operator Algebras · Mathematics 2022-10-28 Claus Köstler , Arundhathi Krishnan

We present a careful approximation of the geodesics in trees of hyperbolic or relatively hyperbolic groups. As an application we prove a combination theorem for finite graphs of relatively hyperbolic groups, with both Farb's and Gromov's…

Group Theory · Mathematics 2008-03-24 F. Gautero

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

We show that the Baum-Connes morphism twisted by a non-unitary representation, defined in [GA08], is an isomorphism for a large class of groups satisfying the Baum-Connes conjecture. Such class contains all the real semi-simple Lie groups,…

K-Theory and Homology · Mathematics 2008-04-29 Maria-Paula Gomez-Aparicio

In this paper, we continue our study of the class of diagram groups. Simply speaking, a diagram is a labelled plane graph bounded by a pair of paths (the top path and the bottom path). To multiply two diagrams, one simply identifies the top…

Group Theory · Mathematics 2007-05-23 Victor Guba , Mark Sapir

Much has been written on reciprocity laws in number theory and their connections with group representations. In this paper we explore more on these connections. We prove a "reciprocity Law" for certain specific representations of semidirect…

Representation Theory · Mathematics 2011-01-04 Sunil K. Chebolu , Jan Minac , Clive Reis

A topological group $G$ is said to have the L\'evy property if it admits a dense subgroup which is decomposed as the union of an increasing sequence of compact subgroups $\mathcal{G}=\{G_i:i\in\mathbb{N}\}$ of $G$ which exhibits…

Group Theory · Mathematics 2025-10-23 Wei Dai , Su Gao , Víctor Hugo Yañez

We have developed polynomial-time algorithms to generate terms of the cogrowth series for groups $\mathbb{Z}\wr \mathbb{Z},$ the lamplighter group, $(\mathbb{Z}\wr \mathbb{Z})\wr \mathbb{Z}$ and the Navas-Brin group $B.$ We have also given…

Group Theory · Mathematics 2020-02-18 Andrew Elvey Price , Anthony J Guttmann

Given a representation V of a group G, there are two natural ways of defining a representation of the group algebra k[G] in the external power V^{\wedge m}. The set L(V) of elements of k[G] for which these two ways give the same result is a…

Representation Theory · Mathematics 2014-04-11 Yurii M. Burman

A closed 3-form $H \in \Omega^3_0(M)$ defines an extension of $\Gamma(TM)$ by $\Omega^2_0(M)$. This fact leads to the definition of the group of $H$-twisted Hamiltonian symmetries $\Ham(M, \JJ; H)$ as well as Hamiltonian action of Lie group…

Differential Geometry · Mathematics 2007-05-23 Shengda Hu