English

Obata's rigidity theorem for metric measure spaces

Metric Geometry 2015-10-30 v3 Differential Geometry

Abstract

We prove Obata's rigidity theorem for metric measure spaces that satisfy a Riemannian curvature-dimension condition. Additionally, we show that a lower bound KK for the generalized Hessian of a sufficiently regular function uu holds if and only if uu is KK-convex. A corollary is also a rigidity result for higher order eigenvalues.

Keywords

Cite

@article{arxiv.1410.5210,
  title  = {Obata's rigidity theorem for metric measure spaces},
  author = {Christian Ketterer},
  journal= {arXiv preprint arXiv:1410.5210},
  year   = {2015}
}

Comments

Theorem 6.1 (Corollary 6.2) is not needed anymore for the proof. Corollary 6.2 has become Corollar 5.4. A rigidity result concerning higher eigenvalues has been added. 20p. Comments are welcome

R2 v1 2026-06-22T06:29:15.130Z