  In this review, we collect several results for conformally standard
stationary spacetimes (SxR,g) obtained in terms of a Finsler metric of Randers
type on the orbit manifold S that we call Fermat metric. This metric is
obtained by applying the relativistic Fermat principle and it turns out that it
encodes all the causal aspects of the spacetime.

Differential Geometry;General Relativity and Quantum Cosmology