Light rays joining two submanifolds in space-times
In the paper [\textit{D. Fortunato}, \textit{F. Giannoni} and \textit{A. Masiello}, J. Geom. Phys. 15, No. 2, 159-188 (1995; Zbl 0819.53037)], lightlike geodesics joining an event to a vertical line have been studied. In this paper, the number of light rays joining two submanifolds in a stationary Lorentz manifold is estimated by the category of the product of the two manifolds under certain additional conditions.
scientific article; zbMATH DE number 1036749
scientific article