English

A note on the diameter of small sub-Riemannian balls

Optimization and Control 2026-03-13 v2 Differential Geometry Metric Geometry

Abstract

We observe that the diameter of small (in a locally uniform sense) balls in C1,1C^{1,1} sub-Riemannian manifolds equals twice the radius. We also prove that, when the regularity of the structure is further lowered to C0C^0, the diameter is arbitrarily close to twice the radius. Both results hold independently of the bracket-generating condition.

Keywords

Cite

@article{arxiv.2505.02790,
  title  = {A note on the diameter of small sub-Riemannian balls},
  author = {Marco Di Marco and Gianluca Somma and Davide Vittone},
  journal= {arXiv preprint arXiv:2505.02790},
  year   = {2026}
}

Comments

6 pages