Stationary–Complete Spacetimes with non-standard splittings and pre-Randers metrics

Using the relativistic Fermat’s principle, we establish a bridge between stationary–complete manifolds which satisfy observer-manifold condition and pre-Randers metrics, namely, Randers metrics without any restriction on one-form. As consequence, give description of causal ladder such spacetimes in terms elements associated with metric: its geodesics distance. We obtain, as applications this interplay, conformal maps Killing submersions, existence multiplicity results for magnetic geodesics.