Second-order symmetric Lorentzian manifolds
arXiv:math/0510099 · doi:10.1063/1.2218194
Abstract
Lorentzian manifolds with vanishing second covariant derivative of the Riemann tensor are studied. Their existence, classification and explicit local expression are considered. Related issues and open questions are briefly commented.
8 pages, Contribution to the Proceedings of the XXVIII Spanish Relativity Meeting, E.R.E.2005 (Oviedo, Spain, 2005)