English

Examples of open manifolds with positive Ricci curvature and non-proper Busemann functions

Differential Geometry 2023-09-06 v2

Abstract

We give the first example of an open manifold with positive Ricci curvature and a non-proper Busemann function at a point. This provides counterexamples to a longtime well-known open question whether the Busemann function at a point of an open manifold with nonnegative Ricci curvature is proper.

Keywords

Cite

@article{arxiv.2203.15211,
  title  = {Examples of open manifolds with positive Ricci curvature and non-proper Busemann functions},
  author = {Jiayin Pan and Guofang Wei},
  journal= {arXiv preprint arXiv:2203.15211},
  year   = {2023}
}

Comments

Added some discussions on the Busemann functions defined by geodesic spheres