Special conformal symmetries in general relativity
A conformal vector field is one satisfying the conformal version of Killing's equation; it is special if the conformal factor is not identically constant but has zero second covariant derivatives. It is shown that such fields generate symmetries of the Ricci tensor, the Einstein tensor and the curvature tensor. The general properties of the somewhat restricted space-times having such symmetries are investigated (an intrinsic family of flat 2-manifolds is determined, the vector field is hypersurface-orthogonal and the space-time is geodesically incomplete).
scientific article; zbMATH DE number 4131183
scientific article