In a metric g.f.f-manifold we study lightlike hypersurfaces M tangent to the characteristic vector fields, and owing to the presence of the f-structure, we determine some decompositions of TM and of a chosen screen distribution obtaining two distributions invariant with respect to the structure. We discuss the existence of a g.f.f -structure on a lightlike hypersurface and, under suitable hypotheses, we obtain an indefinite S-structure on the leaves of an integrable distribution. The existence of totally umbilical lightlike hypersurfaces of an indefinite S-space form is also discussed. Finally, we explicitely describe a lightlike hypersurface of an indefinite S-manifold.
Lightlike hypersurfaces in indefinite S-manifolds
PASTORE, Anna Maria
2010-01-01
Abstract
In a metric g.f.f-manifold we study lightlike hypersurfaces M tangent to the characteristic vector fields, and owing to the presence of the f-structure, we determine some decompositions of TM and of a chosen screen distribution obtaining two distributions invariant with respect to the structure. We discuss the existence of a g.f.f -structure on a lightlike hypersurface and, under suitable hypotheses, we obtain an indefinite S-structure on the leaves of an integrable distribution. The existence of totally umbilical lightlike hypersurfaces of an indefinite S-space form is also discussed. Finally, we explicitely describe a lightlike hypersurface of an indefinite S-manifold.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
