The search session has expired. Please query the service again.
Displaying 321 –
340 of
764
We prove that a connected Riemannian manifold admitting a pair of non-trivial Einstein-Weyl structures with constant scalar curvature is either Einstein, or the dual field of is Killing. Next, let be a complete and connected Riemannian manifold of dimension at least admitting a pair of Einstein-Weyl structures . Then the Einstein-Weyl vector field (dual to the -form ) generates an infinitesimal harmonic transformation if and only if is Killing.
In this paper, we characterize the -dimensional complete spacelike hypersurfaces in a de Sitter space with constant scalar curvature and with two distinct principal curvatures one of which is simple.We show that is a locus of moving -dimensional submanifold , along the principal curvature of multiplicity is constant and is umbilical in and is contained in an -dimensional sphere and is of constant curvature ,where is the arc length of an orthogonal trajectory of the family...
On étudie la complétude géodésique des flots nul-prégéodésiques sur les variétés lorentziennes compactes, ce qui donne une obstruction à être nul-géodésique. On montre que lorsque l’orthogonal du champ de vecteurs engendrant le flot considéré s’intègre en un feuilletage , la complétude du flot se lit sur l’holonomie de . On montre ainsi qu’il n’existe pas de flots nul-géodésiques lisses sur . On montre aussi qu’un -tore lorentzien est nul-complet si et seulement si ses feuilletages de type lumière...
Holomorphic maps of Cartan domains of type four preserving the supports of complex geodesics are characterized, providing, in particular, a new description of holomorphic isometries.
Currently displaying 321 –
340 of
764