English

Nonpositively curved surfaces are Loewner

Differential Geometry 2024-07-04 v2

Abstract

We show that every closed nonpositively curved surface satisfies Loewner's systolic inequality. The proof relies on a combination of the Gauss-Bonnet formula with an averaging argument using the invariance of the Liouville measure under the geodesic flow. This enables us to find a disk with large total curvature around its center yielding a large area.

Keywords

Cite

@article{arxiv.2404.00757,
  title  = {Nonpositively curved surfaces are Loewner},
  author = {Mikhail G. Katz and Stephane Sabourau},
  journal= {arXiv preprint arXiv:2404.00757},
  year   = {2024}
}

Comments

10 pages. To appear in Journal of Geometric Analysis

R2 v1 2026-06-28T15:39:42.418Z