On some type of curvature conditions
In this paper we present a review of recent results on semi-Riemannian manifolds satisfying curvature conditions of pseudosymmetry type.
On special Riemannian -manifolds with distinct constant Ricci eigenvalues
The first author and F. Prufer gave an explicit classification of all Riemannian 3-manifolds with distinct constant Ricci eigenvalues and satisfying additional geometrical conditions. The aim of the present paper is to get the same classification under weaker geometrical conditions.
On submanifolds in a space with Sasakian 3-structure
On Super Quasi Einstein Manifold
On symmetric Riemannian manifolds.
On the central paths and Cauchy trajectories in semidefinite programming
In this work, we study the properties of central paths, defined with respect to a large class of penalty and barrier functions, for convex semidefinite programs. The type of programs studied here is characterized by the minimization of a smooth and convex objective function subject to a linear matrix inequality constraint. So, it is a particular case of convex programming with conic constraints. The studied class of functions consists of spectrally defined functions induced by penalty or barrier...
On the characteristic connection of gwistor space
We give a brief presentation of gwistor spaces, which is a new concept from G 2 geometry. Then we compute the characteristic torsion T c of the gwistor space of an oriented Riemannian 4-manifold with constant sectional curvature k and deduce the condition under which T c is ∇c-parallel; this allows for the classification of the G 2 structure with torsion and the characteristic holonomy according to known references. The case of an Einstein base manifold is envisaged.
On the Classification of Lorentzian Sasaki Space Forms
On the completeness of total spaces of horizontally conformal submersions
In this paper, we address the completeness problem of certain classes of Riemannian metrics on vector bundles. We first establish a general result on the completeness of the total space of a vector bundle when the projection is a horizontally conformal submersion with a bound condition on the dilation function, and in particular when it is a Riemannian submersion. This allows us to give completeness results for spherically symmetric metrics on vector bundle manifolds and eventually for the class...
On the concircular curvature tensor of a -manifold.
On the curvature of -contact Riemannian manifolds with constant -sectional curvature with a submersion of geodesic fibres.
On the differential geometry of frame bundles of Riemannian manifolds.
On the existence of certain types of Riemannian metrics
On the existence of f-recurrent (LCS)n-manifolds.
On the existence of generalized quasi-Einstein manifolds
The object of the present paper is to study a type of Riemannian manifold called generalized quasi-Einstein manifold. The existence of a generalized quasi-Einstein manifold have been proved by non-trivial examples.
On the existence of pseudosymmetric Kähler manifolds
It is proved that there exists a non-semisymmetric pseudosymmetric Kähler manifold of dimension 4.
On the finiteness of the fundamental group of a compact shrinking Ricci soliton
Myers's classical theorem says that a compact Riemannian manifold with positive Ricci curvature has finite fundamental group. Using Ambrose's compactness criterion or J. Lott's results, M. Fernández-López and E. García-Río showed that the finiteness of the fundamental group remains valid for a compact shrinking Ricci soliton. We give a self-contained proof of this fact by estimating the lengths of shortest geodesic loops in each homotopy class.
On the geodesics flow of tori without conjugate points.
On the Geometry of Moduli Spaces.
On the geometry of tangent bundles with the metric II+III
The main purpose of this paper is to investigate some relations between the flatness or locally symmetric property on the tangent bundle TM equipped with the metric II+III and the same property on the base manifold M and study geodesics by means of the adapted frame on TM.