English

Polyhedral realisations of finite arc complexes using strip deformations

Differential Geometry 2025-05-05 v1 Combinatorics

Abstract

We study infinitesimal deformations of complete hyperbolic surfaces with boundary and with ideal vertices, possibly decorated with horoballs. ``Admissible'' deformations are the ones that pull all horoballs apart; they form a convex cone of deformations. We describe this cone in terms of the arc complex of the surface: specifically, this paper focuses on the surfaces for which that complex is finite. Those surfaces form four families: (ideal) polygons, once-punctured polygons, one-holed polygons (or ``crowns''), and M\"obius strips with spikes. In each case, we describe a natural simplicial decomposition of the projectivised admissible cone and of each of its faces, realizing them as appropriate arc complexes.

Keywords

Cite

@article{arxiv.2505.01285,
  title  = {Polyhedral realisations of finite arc complexes using strip deformations},
  author = {François Guéritaud and Pallavi Panda},
  journal= {arXiv preprint arXiv:2505.01285},
  year   = {2025}
}
R2 v1 2026-06-28T23:19:16.539Z