English

An Obata-type theorem on a three-dimensional CR manifold

Differential Geometry 2012-08-31 v3 Analysis of PDEs

Abstract

We prove a CR version of the Obata's result for the first eigenvalue of the sub-Laplacian in the setting of a compact strictly pseudoconvex pseudohermitian three dimensional manifold with non-negative CR-Panietz operator which satisfies a Lichnerowicz type condition. We show that if the first positive eigenvalue of the sub-Laplacian takes the smallest possible value then, up to a homothety of the pseudohermitian structure, the manifold is the standard Sasakian three dimensional unit sphere.

Keywords

Cite

@article{arxiv.1208.1040,
  title  = {An Obata-type theorem on a three-dimensional CR manifold},
  author = {Stefan Ivanov and Dimiter Vassilev},
  journal= {arXiv preprint arXiv:1208.1040},
  year   = {2012}
}

Comments

Improved exposition and remarks on references and citations. arXiv admin note: substantial text overlap with arXiv:1203.5812

R2 v1 2026-06-21T21:46:32.785Z