English

On Almost-Riemannian Surfaces

Differential Geometry 2012-03-06 v1

Abstract

An almost-Riemannian structure on a surface is a generalized Riemannian structure whose local orthonormal frames are given by Lie bracket generating pairs of vector fields that can become collinear. The distribution generated locally by orthonormal frames has maximal rank at almost every point of the surface, but in general it has rank 1 on a nonempty set which is generically a smooth curve. In this paper we provide a short introduction to 2-dimensional almost-Riemannian geometry highlighting its novelties with respect to Riemannian geometry. We present some results that investigate topological, metric and geometric aspects of almost- Riemannian surfaces from a local and global point of view.

Keywords

Cite

@article{arxiv.1203.0949,
  title  = {On Almost-Riemannian Surfaces},
  author = {Roberta Ghezzi},
  journal= {arXiv preprint arXiv:1203.0949},
  year   = {2012}
}

Comments

arXiv admin note: text overlap with arXiv:math/0609566 by other authors

R2 v1 2026-06-21T20:29:10.854Z