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Related papers: Hyperbolic hydra

200 papers

Part 1 : We remark that the conjugacy problem for pairs of hyperbolic au- tomorphisms of a finitely presented group (typically a free group) is decidable. The solution that we propose uses the isomorphism problem for the suspensions, and…

Group Theory · Mathematics 2020-07-20 François Dahmani

We propose a new model for random quotients of groups using independent random walks. In this model, we show that random quotients of acylindrical hyperbolic groups asymptotically almost surely remain acylindrically hyperbolic. Our main…

Group Theory · Mathematics 2026-01-28 Carolyn Abbott , Daniel Berlyne , Giorgio Mangioni , Thomas Ng , Alexander J. Rasmussen

Let G be a group which is hyperbolic relative to a collection of subgroups A, and it is also hyperbolic relative to a collection of subgroups B. Suppose that the collection A contains B. We characterize, for subgroups of G, when…

Group Theory · Mathematics 2011-05-03 Eduardo Martinez-Pedroza

We prove that infinitely presented graphical $Gr(7)$ small cancellation groups are acylindrically hyperbolic. In particular, infinitely presented classical $C(7)$-groups and, hence, classical $C'(\frac{1}{6})$-groups are acylindrically…

Group Theory · Mathematics 2016-02-10 Dominik Gruber , Alessandro Sisto

We introduce a number of new tools for the study of relatively hyperbolic groups. First, given a relatively hyperbolic group G, we construct a nice combinatorial Gromov hyperbolic model space acted on properly by G, which reflects the…

Group Theory · Mathematics 2009-03-29 Daniel Groves , Jason Fox Manning

We present a new notion of non-positively curved groups: the collection of discrete countable groups acting (AU-)acylindrically on finite products of $\delta$-hyperbolic spaces with general type factors and associated subdirect products.…

Group Theory · Mathematics 2025-12-29 Sahana Balasubramanya , Talia Fernos

We begin the investigation of Gamma-limit groups, where Gamma is a torsion-free group which is hyperbolic relative to a collection of free abelian subgroups. Using the results of Drutu and Sapir, we adapt the results from math.GR/0404440 to…

Group Theory · Mathematics 2016-01-20 Daniel Groves

We prove that hyperbolic groups with logarithmic separation profiles split over cyclic groups. This shows that such groups can be inductively built from Fuchsian groups and free groups by amalgamations and HNN extensions over finite or…

Group Theory · Mathematics 2025-03-12 Nir Lazarovich , Corentin Le Coz

We call a finitely generated group lacunary hyperbolic if one of its asymptotic cones is an R-tree. We characterize lacunary hyperbolic groups as direct limits of Gromov hyperbolic groups satisfying certain restrictions on the hyperbolicity…

Group Theory · Mathematics 2009-04-29 A. Yu. Olshanskii , D. V. Osin , M. V. Sapir

We give estimates on asymptotic dimensions of products of general hyperbolic spaces with following applications to the hyperbolic groups. We give examples of strict inequality in the product theorem for the asymptotic dimension in the class…

Differential Geometry · Mathematics 2007-05-23 Nina Lebedeva

We study the subgroup structure, Hecke algebras, quasi-regular representations, and asymptotic properties of some fractal groups of branch type. We introduce parabolic subgroups, show that they are weakly maximal, and that the corresponding…

Group Theory · Mathematics 2009-11-27 Laurent Bartholdi , Rostislav I. Grigorchuk

Given a finitely generated subgroup $\Gamma \le \mathrm{Out}(\mathbb{F})$ of the outer automorphism group of the rank $r$ free group $\mathbb{F} = F_r$, there is a corresponding free group extension $1 \to \mathbb{F} \to E_{\Gamma} \to…

Geometric Topology · Mathematics 2018-03-16 Spencer Dowdall , Samuel J. Taylor

Let $m$ and $k$ be integers such that $|m|, \, |k| >1$ and $\gcd (m,k)=1$. We show that all Baumslag-Solitar groups $BS(m,mk)$ are non-residually finite groups hyperbolic relative to residually finite subgroups. By a result of Osin (2007),…

Group Theory · Mathematics 2019-03-07 Jan Kim , Donghi Lee

We give solutions to several decision problems in word hyperbolic groups

Group Theory · Mathematics 2007-05-23 Jean-Philippe Preaux

We determine the maximal hyperbolic reflection groups associated to the quadratic forms $-3x_0^2 + x_1^2 + ... + x_n^2$, $n \ge 2$, and present the Coxeter schemes of their fundamental polyhedra. These groups exist in dimensions up to 13,…

Group Theory · Mathematics 2010-09-29 John Mcleod

We develop the geometry of folding paths in Outer space and, as an application, prove that the complex of free factors of a free group of finite rank is hyperbolic.

Group Theory · Mathematics 2014-01-23 Mladen Bestvina , Mark Feighn

A basic point about hyperbolic groups is that they have "spaces at infinity" which are spaces of homogeneous type in the sense of Coifman and Weiss, and with a lot of self-similarity coming from the group. This short survey deals with some…

Classical Analysis and ODEs · Mathematics 2007-05-23 Stephen Semmes

We prove that every finitely presented group with positive first $\ell^2$-Betti number that virtually surjects onto $\mathbb Z$ is acylindrically hyperbolic. In particular, this implies acylindrical hyperbolicity of finitely presented…

Group Theory · Mathematics 2018-05-16 D. Osin

We construct examples of inhomogeneous isoparametric real hypersurfaces in complex hyperbolic spaces.

Differential Geometry · Mathematics 2010-11-24 J. Carlos Diaz-Ramos , Miguel Dominguez-Vazquez

We present a new notion of non-positively curved groups: the collection of discrete countable groups acting (AU-)acylindrically on finite products of $\delta$-hyperbolic spaces with general type factors. Inspired by the classical theory of…

Group Theory · Mathematics 2025-12-30 Sahana Balasubramanya , Talia Fernos