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Related papers: Contractible, hyperbolic but non-CAT(0) complexes

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Let G be a group acting geometrically on a CAT(0) cube complex X. We prove first that G is hyperbolic relative to the collection P of subgroups if and only if the simplicial boundary of X is the disjoint union of a nonempty discrete set,…

Group Theory · Mathematics 2016-06-15 Jason Behrstock , Mark F. Hagen

We prove a combination theorem for hyperbolic groups, in the case of groups acting on complexes displaying combinatorial features reminiscent of non-positive curvature. Such complexes include for instance weakly systolic complexes and…

Group Theory · Mathematics 2019-09-19 Alexandre Martin , Damian Osajda

Block and Weinberger show that an arithmetic manifold can be endowed with a positive scalar curvature metric if and only if its $\rationals$-rank exceeds 2. We show in this article that these metrics are never in the same coarse class as…

Differential Geometry · Mathematics 2007-05-23 Stanley S. Chang

Many geometric structures associated to surface groups can be encoded in terms of invariant cross ratios on their circle at infinity; examples include points of Teichm\"uller space, Hitchin representations and geodesic currents. We add to…

Geometric Topology · Mathematics 2026-03-25 Jonas Beyrer , Elia Fioravanti

In this article we give an explicit algorithm which will determine, in a discrete and computable way, whether a finite piecewise Euclidean complex is non-positively curved. In particular, given such a complex we show how to define a boolean…

Geometric Topology · Mathematics 2012-05-16 Murray Elder , Jon McCammond

We study finite foldable cubical complexes of nonpositive curvature (in the sense of A.D. Alexandrov). We show that such a complex X admits a graph of spaces decomposition. It is also shown that when dim X=3, X contains a closed rank one…

Metric Geometry · Mathematics 2014-10-01 Xiangdong Xie

We prove that a CAT(0) free-by-cyclic tubular group with one vertex is virtually special, but many of them cannot virtually act freely and cocompactly on CAT(0) cube complexes. This partially confirms a question of Brady--Soroko…

Group Theory · Mathematics 2025-04-22 Xiaolei Wu , Shengkui Ye

We prove that many relatively hyperbolic groups obtained by relative strict hyperbolization admit a cocompact action on a CAT(0) cubical complex. Under suitable assumptions on the peripheral subgroups, these groups are residually finite and…

Group Theory · Mathematics 2025-04-04 Daniel Groves , Jean-François Lafont , Jason Fox Manning , Lorenzo Ruffoni

We define the class of high dimensional graph manifolds. These are compact smooth manifolds supporting a decomposition into finitely many pieces, each of which is diffeomorphic to the product of a torus with a finite volume hyperbolic…

Differential Geometry · Mathematics 2016-03-22 Roberto Frigerio , Jean-Francois Lafont , Alessandro Sisto

We introduce the bounded packing property for a subgroup of a countable discrete group G. This property gives a finite upper bound on the number of left cosets of the subgroup that are pairwise close in G. We establish basic properties of…

Group Theory · Mathematics 2014-11-11 G. Christopher Hruska , Daniel T. Wise

We show that the homological finiteness length of a non-uniform lattice on a locally finite CAT(0) n-dimensional polyhedral complex is less than n. As a corollary, we obtain an upper bound for the homological finiteness length of arithmetic…

Group Theory · Mathematics 2011-08-02 Giovanni Gandini

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 seminal result in geometric group theory is that a 1-ended hyperbolic group has a locally connected visual boundary. As a consequence, a 1-ended hyperbolic group also has a path connected visual boundary. In this paper, we study when this…

Group Theory · Mathematics 2019-10-18 Michael Ben-Zvi

We construct compact hyperbolic 3-manifolds with totally geodesic boundary, such that the closed 3-pseudomanifolds obtained by coning off the boundary components are negatively curved and contain locally convex subspaces whose fundamental…

Geometric Topology · Mathematics 2026-02-11 Jason Manning , Lorenzo Ruffoni

We prove that there are infinitely many pairwise non-commensurable hyperbolic $n$-manifolds that have the same ambient group and trace ring, for any $n \geq 3$. The manifolds can be chosen compact if $n \geq 4$.

Geometric Topology · Mathematics 2020-07-02 Olivier Mila

We examine a graph $\Gamma$ encoding the intersection of hyperplane carriers in a CAT(0) cube complex $\widetilde X$. The main result is that $\Gamma$ is quasi-isometric to a tree. This implies that a group $G$ acting properly and…

Group Theory · Mathematics 2015-03-18 Mark F. Hagen

Let $V$ be a finite graph and let $\phi:V\rightarrow V$ be an irreducible train track map whose mapping torus has word-hyperbolic fundamental group $G$. Then $G$ acts freely and cocompactly on a CAT(0) cube complex.

Group Theory · Mathematics 2016-08-17 Mark F. Hagen , Daniel T. Wise

The class of quasi-median graphs is a generalisation of median graphs, or equivalently of CAT(0) cube complexes. The purpose of this thesis is to introduce these graphs in geometric group theory. In the first part of our work, we extend the…

Group Theory · Mathematics 2017-12-06 Anthony Genevois

This paper is a survey dedicated to the following question: given a group acting on some CAT(0) cube complex, how to exploit this action to determine whether or not the group is Gromov / relatively / acylindrically hyperbolic? As much as…

Group Theory · Mathematics 2019-04-29 Anthony Genevois

We show that any group that is hyperbolic relative to virtually nilpotent subgroups, and does not admit peripheral splittings, contains a quasi-isometrically embedded copy of the hyperbolic plane. In natural situations, the specific…

Group Theory · Mathematics 2020-11-09 John M. Mackay , Alessandro Sisto