We deal with complete linear Weingarten spacelike hypersurfaces immersed in the de
Sitter space, that is, spacelike hypersurfaces of de Sitter space whose mean and scalar
curvatures are linearly related. In this setting, we apply a suitable extension
of the generalized maximum principle of Omori–Yau to show that either
such a spacelike hypersurface must be totally umbilical or there holds a
sharp estimate for the norm of its total umbilicity tensor, with equality
characterizing hyperbolic cylinders of de Sitter space. We also study the
parabolicity of these spacelike hypersurfaces with respect to a Cheng–Yau modified
operator.
Keywords
de Sitter space, linear Weingarten hypersurfaces, spacelike
hypersurfaces, totally umbilical hypersurfaces, hyperbolic
cylinders, parabolicity