Harmonic curvatures in Lorentzian space.
Harmonic maps of Lorentz surfaces, quadratic differentials and paraholomorphicity.
Harmonicity of vector fields on four-dimensional generalized symmetric spaces
Let (M = G/H;g)denote a four-dimensional pseudo-Riemannian generalized symmetric space and g = m + h the corresponding decomposition of the Lie algebra g of G. We completely determine the harmonicity properties of vector fields belonging to m. In some cases, all these vector fields are critical points for the energy functional restricted to vector fields. Vector fields defining harmonic maps are also classified, and the energy of these vector fields is explicitly calculated.
Higher order Ossermann pseudo-Riemannian manifolds of neutral signature .
Holonomy and projective equivalence in 4-dimensional Lorentz manifolds.
Holonomy theory and 4-dimensional Lorentz manifolds.
Homogeneous Einstein manifolds based on symplectic triple systems
For each simple symplectic triple system over the real numbers, the standard enveloping Lie algebra and the algebra of inner derivations of the triple provide a reductive pair related to a semi-Riemannian homogeneous manifold. It is proved that this is an Einstein manifold.
Homogeneous Lorentz manifolds with simple isometry group.
Homogeneous Lorentzian 3-manifolds with a parallel null vector field.
Homogeneous Lorentzian structures on some Gödel-Levichev's spacetimes, and associated reductive decompositions.
Horizons in five-dimensional theory
Hyperbolic angle function in the Lorentzian plane
Hypersurfaces in a conformally flat space with curvature collineation.
Hypersurfaces in spaces of constant curvature satisfying some Ricci-type equations
We investigate hypersurfaces M in semi-Riemannian spaces of constant curvature satisfying some Ricci-type equations and for which the tensor H³ is a linear combination of the tensor H², the second fundamental tensor H of M and the metric tensor g of M.