EXTENSION OF THE DE SITTER KINK

A space-time, locally identical to the usual de Sitter space-time but globally different because of a kink in its light cone field, is described in various coordinate systems. Two separate coordinate patches are needed. Each original patch is geodesically incomplete and so is extended by the Kruskal method. The space-time, which is not globally hyperbolic, is shown to be foliated by a family of hypersurfaces each of which is homeomorphic to a three-sphere but none of which is everywhere spacelike.