English

Perimeter approximation of convex discs in the hyperbolic plane and on the sphere

Metric Geometry 2026-04-13 v1

Abstract

Eggleston (1957) proved that in the Euclidean plane the best approximating convex nn-gon to a convex disc KK is always inscribed in KK if we measure the distance by perimeter deviation. We prove that the analogue of Eggleston's statement holds in the hyperbolic plane, and we give an example showing that it fails on the sphere.

Keywords

Cite

@article{arxiv.1902.03655,
  title  = {Perimeter approximation of convex discs in the hyperbolic plane and on the sphere},
  author = {Ferenc Fodor},
  journal= {arXiv preprint arXiv:1902.03655},
  year   = {2026}
}