English

Characterizations of the sphere by means of point-projections

Metric Geometry 2026-02-03 v3

Abstract

In this work we prove the following: let KK be a convex body in the Euclidean space Rn\mathbb{R}^n, n3n\geq 3, contained in the interior of the unit ball of Rn\mathbb{R}^n, and let pRnp\in \mathbb{R}^n be a point such that, from each point of Sn1\mathbb{S}^{n-1}, KK looks centrally symmetric and pp appears as the center, then KK is a ball.

Keywords

Cite

@article{arxiv.2007.04516,
  title  = {Characterizations of the sphere by means of point-projections},
  author = {J. Jeronimo_Castro and E. Morales-Amaya and D. J. Verdusco Hernández},
  journal= {arXiv preprint arXiv:2007.04516},
  year   = {2026}
}