English
Related papers

Related papers: Largeness of LERF and 1-relator groups

200 papers

We study a class of two-generator two-relator groups, denoted $J_n(m,k)$, that arise in the study of relative asphericity as groups satisfying a transitional curvature condition. Particular instances of these groups occur in the literature…

Group Theory · Mathematics 2016-07-08 William A. Bogley , Gerald Williams

Residual finiteness growth measures how well-approximated a group is by its finite quotients. We prove that some related growth functions characterize linearity for a class of groups including all hyperbolic groups.

Group Theory · Mathematics 2016-11-16 Khalid Bou-Rabee , D. B. McReynolds

We prove that the automorphism group of every infinitely-ended finitely generated group is acylindrically hyperbolic. In particular $\mathrm{Aut}(\mathbb{F}_n)$ is acylindrically hyperbolic for every $n\ge 2$. More generally, if $G$ is a…

Group Theory · Mathematics 2021-09-17 Anthony Genevois , Camille Horbez

Consider a one-ended word-hyperbolic group. If it is the fundamental group of a graph of free groups with cyclic edge groups then either it is the fundamental group of a surface or it contains a finitely generated one-ended subgroup of…

Group Theory · Mathematics 2014-11-11 Henry Wilton

It is well-known that random groups with at least as many relators as generators have vanishing first betti number with high probability. In this paper we extend this question and study maps from few-relators random groups to infinite…

Group Theory · Mathematics 2019-02-19 Gareth Wilkes

We revise the enumeration of the imprimitive rank two quaternionic reflection groups, adding missing groups and establishing isomorphisms between groups in the published tables. The isomorphisms are obtained as a consequence of the…

Group Theory · Mathematics 2025-10-28 Donald E Taylor

The study of word hyperbolic groups is a prominent topic in geometric group theory; however word hyperbolic groups are defined by a geometric condition which does not extend naturally to semigroups. We propose a linguistic definition.…

Group Theory · Mathematics 2007-05-23 Andrew Duncan , Robert H. Gilman

A group is known as `large' if some finite index subgroup admits a surjective homomorphism onto a non-abelian free group. In this paper, we give a necessary and sufficient condition for a finitely presented group to be large, in terms of…

Group Theory · Mathematics 2007-05-23 Marc Lackenby

Let $G$ be a group that is relatively hyperbolic with respect to a collection of subgroups $\{H_{\lambda}\}_{\lambda\in \Lambda}$. Suppose that $G$ is given by a finite relative presentation $\mathcal{P}$ with respect to this collection. We…

Group Theory · Mathematics 2025-01-09 Oleg Bogopolski

Sela introduced limit groups in his work on the Tarski problem, and showed that each limit group has a cyclic hierarchy. In this paper, a class of relatively hyperbolic groups, equipped with a hierarchy similar to the one for limit groups,…

Group Theory · Mathematics 2023-02-13 Aaron W. Messerla

We show that if $\Gamma$ is an infinite finitely generated finitely presented sofic group with zero first $L^{2}$ Betti number then the von Neumann algebra $L(\Gamma)$ is strongly $1$-bounded in the sense of Jung. In particular,…

Operator Algebras · Mathematics 2016-09-16 D. Shlyakhtenko

We provide polynomial lower bounds for residual finiteness of residually finite, finitely generated solvable groups that admit infinite order elements in the Fitting subgroup of strict distortion at least exponential. For this class of…

Group Theory · Mathematics 2019-12-03 Mark Pengitore

We give examples of hyperbolic groups with finite-rank free subgroups of huge (Ackermannian) distortion.

Group Theory · Mathematics 2011-05-10 Noel Brady , Will Dison , Tim Riley

The first $\ell^2$ Betti number of a group is non-decreasing under various embeddings arising from first order logic. Strict inequality is proved for elementary embeddings of non-abelian proper subgroups within torsion free hyperbolic…

Group Theory · Mathematics 2026-05-21 Connor MacMahon

Suppose $C(G)$ denotes the set of all cyclic subgroups of a finite group $G$, and $\mathcal{O}_{2}(G)$ denotes the number of elements of order $2$ in $G$. In [Marius T., Finite groups with a certain number of cyclic subgroups. The American…

Group Theory · Mathematics 2025-08-08 Vaibhav Chhajer , Sumana Hatui , Palash Sharma

We show that the first $L^2$-betti number of a finitely generated residually finite group can be estimated from below by using ordinary first betti numbers of finite index normal subgroups. As an application we construct a finitely…

Group Theory · Mathematics 2010-12-17 W. Lück , D. Osin

A subset of a group is characteristic if it is invariant under every automorphism of the group. We study word length in fundamental groups of closed hyperbolic surfaces with respect to characteristic generating sets consisting of a finite…

Group Theory · Mathematics 2008-04-07 Danny Calegari

We algebraically characterize free by cyclic groups that have coarse medians, and prove that this is equivalent to the a priori stronger properties of being colourable hierarchically hyperbolic groups and being quasi-isometric to CAT(0)…

Group Theory · Mathematics 2026-05-19 Eliot Bongiovanni , Pritam Ghosh , Funda Gültepe , Mark Hagen

A group $G$ with conjugation operation is a rack. We call such racks \emph{group racks}. In this paper we study finite group racks via their subrack lattices. Heckenberger, Shareshian, and Welker proved that the isomorphism type of the…

Group Theory · Mathematics 2026-04-14 Selçuk Kayacan

We show that a free-by-cyclic group with a polynomially growing monodromy is subgroup separable exactly when it is virtually $F_n \times \mathbb{Z}$. We also prove that random deficiency 1 groups are not subgroup separable with positive…

Group Theory · Mathematics 2023-09-06 Monika Kudlinska