# INTRODUCTION TO GEOMETRY

@inproceedings{Lockhart2007INTRODUCTIONTG, title={INTRODUCTION TO GEOMETRY}, author={Paul Douglas Lockhart}, year={2007} }

This paper is an introduction to Riemannian and semi-Riemannian manifolds of constant sectional curvature. We will introduce the concepts of moving frames, curvature, geodesics and homogeneity on six model spaces: Rn, Sn, and Hn in Riemannian geometry, and Rn,1, dSn and AdSn in semiRiemannian geometry. We then claim that up to isometries, these are the only examples in both settings, and state a classification theorem to support that. Some terminology from general relativity will be introduced…

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