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On the Coarse Lusternik-Schnirelmann Category of Groups

Geometric Topology 2025-11-13 v2 Algebraic Topology Group Theory Metric Geometry

Abstract

We introduce a coarse analog of the classical Lusternik-Schnirelmann category which we denote by c-cat\text{c-cat}, defined for metric spaces in the coarse homotopy category. This provides a new tool for studying large-scale topological properties of groups and spaces. We establish that c-cat\text{c-cat} is a coarse homotopy invariant and prove a lower-bound p-cat(Γ)c-cat(Γ)\text{p-cat}(\Gamma)\leq \text{c-cat}(\Gamma) for geometrically finite groups Γ\Gamma, where p-cat\text{p-cat} denotes the proper LS-category introduced in 1992 by Ayala and co-authors. We also prove an upper bound c-cat(Γ)asdim(Γ)\text{c-cat}(\Gamma) \leq \text{asdim}(\Gamma) for bicombable 1-ended groups which are semistable at \infty.

Keywords

Cite

@article{arxiv.2510.10367,
  title  = {On the Coarse Lusternik-Schnirelmann Category of Groups},
  author = {Aditya De Saha},
  journal= {arXiv preprint arXiv:2510.10367},
  year   = {2025}
}

Comments

20 Pages, 3 figures. Re-uploaded to include figures and author contact information