Semi-invariant submanifolds of a Lorentzian para-Sasakian manifold.
Semiparallel isometric immersions of 3-dimensional semisymmetric Riemannian manifolds
A Riemannian manifold is said to be semisymmetric if . A submanifold of Euclidean space which satisfies is called semiparallel. It is known that semiparallel submanifolds are intrinsically semisymmetric. But can every semisymmetric manifold be immersed isometrically as a semiparallel submanifold? This problem has been solved up to now only for the dimension 2, when the answer is affirmative for the positive Gaussian curvature. Among semisymmetric manifolds a special role is played by the foliated...
Semi-parallel Lightlike Hypersurfaces of Indefinite Cosymplectic Space Forms
Semi-riemannian Manifolds Whose Weyl Tensor is a Kulkarni--nomizu Square
Semi-Riemannian manifolds whose Weyl tensor is a Kulkarni-Nomizu square.
Semi-symmetric -spaces
We determine explicitly the local structure of a semi-symmetric -space.
Semisymmetry and Ricci-symmetry for Hypersurfaces of Semi-euclidean Spaces
Several cohomology algebras connected with Poisson structure.
Shape Operators and Structure Tensors of Real Hypersurfaces in Nonflat Quaternionic Space Forms
We characterize curvature-adapted real hypersurfaces in nonflat quaternionic space forms in terms of their shape operators and structure tensors.
Shells of monotone curves
We determine in the form of curves corresponding to strictly monotone functions as well as the components of affine connections for which any image of under a compact-free group of affinities containing the translation group is a geodesic with respect to . Special attention is paid to the case that contains many dilatations or that is a curve in . If is a curve in and is the translation group then we calculate not only the components of the curvature and the Weyl tensor but...
Simple conformally symmetric manifolds with metric semi-symmetric connection
Singular Klein manifolds.
Singular points of lightlike hypersurfaces of the de Sitter space.
Slant and Legendre curves in Bianchi-Cartan-Vranceanu geometry
We study Legendre and slant curves for Bianchi-Cartan-Vranceanu metrics. These curves are characterized through the scalar product between the normal at the curve and the vertical vector field and in the helix case they have a proper (non-harmonic) mean curvature vector field. The general expression of the curvature and torsion of these curves and the associated Lancret invariant (for the slant case) are computed as well as the corresponding variant for some particular cases. The slant (particularly...
Slant submanifolds with prescribed scalar curvature into cosymplectic space form.
Slant surfaces with prescribed Gaussian curvature.
Smooth, but not Complex-Analytic Pluripolar Sets.
Some Additive Designs
Given a finite additive abelian group and an integer , with , denote by the simple incidence structure whose point-set is and whose blocks are the -subsets of such that . It is known (see [Caggegi, A., Di Bartolo, A., Falcone, G.: Boolean 2-designs and the embedding of a 2-design in a group arxiv 0806.3433v2, (2008), 1–8.]) that is a 2-design, if is an elementary abelian -group with a prime divisor of . From [Caggegi, A., Falcone, G., Pavone, M.: On the additivity of block...
Some characteristics of curvature tensors of nonsymmetric affine connexion.
Some characterizations of 2-symmetric submanifolds in spaces of constant curvature