English

The quasi-redirecting Boundary

Group Theory 2024-06-25 v1

Abstract

We generalize the notion of Gromov boundary to a larger class of metric spaces beyond Gromov hyperbolic spaces. Points in this boundary are classes of quasi-geodesic rays and the space is equipped with a topology that is naturally invariant under quasi-isometries. It turns out that this boundary is compatible with other notions of boundary in many ways; it contains the sublinearly Morse boundary as a topological subspace and it matches the Bowditch boundary of relative hyperbolic spaces when the peripheral subgroups have no intrinsic hyperbolicity. We also give a complete description of the boundary of the Croke-Kleiner group where the quasi-redirecting boundary reveals a new class of QI-invariant, Morse-like quasi-geodesics.

Keywords

Cite

@article{arxiv.2406.16794,
  title  = {The quasi-redirecting Boundary},
  author = {Yulan Qing and Kasra Rafi},
  journal= {arXiv preprint arXiv:2406.16794},
  year   = {2024}
}

Comments

56 pages, 10 figures

R2 v1 2026-06-28T17:17:31.606Z