1Heriot-Watt University, Edinburgh, UK 2University of Toronto, Canada; Institute for Advanced Study in Mathematics of HIT, Harbin, Heilongjiang, P. R. China
Groups, geometry, and dynamics, Tome 19 (2025) no. 4, pp. 1425-1443
We show that a quasi-geodesic in an injective metric space is Morse if and only if it is strongly contracting. Since mapping class groups and, more generally, hierarchically hyperbolic groups act properly and coboundedly on injective metric spaces, we deduce various consequences relating, for example, to growth tightness and genericity of pseudo-Anosovs/Morse elements. Moreover, we show that injective metric spaces have the Morse local-to-global property and that a non-virtually cyclic group acting properly and coboundedly on an injective metric space is acylindrically hyperbolic if and only if contains a Morse ray. We also show that strongly contracting geodesics of a space stay strongly contracting in the injective hull of that space.
Alessandro Sisto 
1
;
Abdul Zalloum 
2
1
Heriot-Watt University, Edinburgh, UK
2
University of Toronto, Canada; Institute for Advanced Study in Mathematics of HIT, Harbin, Heilongjiang, P. R. China
Alessandro Sisto; Abdul Zalloum. Morse subsets of injective spaces are strongly contracting. Groups, geometry, and dynamics, Tome 19 (2025) no. 4, pp. 1425-1443. doi: 10.4171/ggd/811
@article{10_4171_ggd_811,
author = {Alessandro Sisto and Abdul Zalloum},
title = {Morse subsets of injective spaces are strongly contracting},
journal = {Groups, geometry, and dynamics},
pages = {1425--1443},
year = {2025},
volume = {19},
number = {4},
doi = {10.4171/ggd/811},
url = {http://geodesic.mathdoc.fr/articles/10.4171/ggd/811/}
}
TY - JOUR
AU - Alessandro Sisto
AU - Abdul Zalloum
TI - Morse subsets of injective spaces are strongly contracting
JO - Groups, geometry, and dynamics
PY - 2025
SP - 1425
EP - 1443
VL - 19
IS - 4
UR - http://geodesic.mathdoc.fr/articles/10.4171/ggd/811/
DO - 10.4171/ggd/811
ID - 10_4171_ggd_811
ER -
%0 Journal Article
%A Alessandro Sisto
%A Abdul Zalloum
%T Morse subsets of injective spaces are strongly contracting
%J Groups, geometry, and dynamics
%D 2025
%P 1425-1443
%V 19
%N 4
%U http://geodesic.mathdoc.fr/articles/10.4171/ggd/811/
%R 10.4171/ggd/811
%F 10_4171_ggd_811