An introduction to Cartan Geometries
A principal bundle with a Lie group consists of a manifold and a free proper smooth -action . There is a unique smooth manifold structure on the quotient space such that the canonical map is smooth. is called a base manifold and stands for the bundle. The most fundamental examples of principal bundles are the homogeneous spaces , where is a closed subgroup of . The pair is a Klein pair. A model geometry consists of a Klein pair and a Lie group with Lie algebra . In this...