Maximal and Willmore Null Hypersurfaces in Generalized Robertson-Walker Spacetimes
Maximal and Willmore Null Hypersurfaces in Generalized Robertson-Walker Spacetimes
We establish after some technical results a characterization of maximal null hypersurfaces in terms of a constant mean curvature screen foliation (in the slices) induced by the Chen's vector field. Thereafter, bounds are provided for both the squared norm of the (screen) shape operator for non totally geodesic maximal null …