Year: 2025
Type: article
Abstract: This paper presents a study of the well‐known marked length spectrum rigidity problem in the coarse‐geometric setting. For any two (possibly non‐proper) group actions and with contracting property, we prove that if the two actions have the same marked length spectrum, then the orbit map must be a rough isometry. In the special case of cusp‐uniform actions, the rough isometry can be extended to the entire space. This generalises the existing results in hyperbolic groups and relatively hyperbolic groups. In addition, we prove a finer marked length spectrum rigidity from confined subgroups and further, geometrically dense subgroups. Our proof is based on the Extension Lemma and uses purely elementary metric geometry. This study produces new results and recovers existing ones for many more interesting groups through a unified and elementary approach.
DOI: 10.1112/jlms.70146
Authors: Renxing Wan, Xiaoyu Xu, Wenyuan Yang
Institutions: East China Normal University, Peking University
Language: English
Subfield: Geometry and Topology
Field: Mathematics
Domain: Physical Sciences
Open Access status: green
OpenAlex ID: W4409309979
