A detailed study of the singularity theorems is presented. I discuss the plausibility and
reasonability of their hypotheses, the applicability and implications of the theorems, as well …

We discuss the question of whether or not inflationary spacetimes can be geodesically
complete in the infinite past. Geodesic completeness is a necessary condition for averting an …

The geometry and, especially, the geodesics of a class of spacetimes generalizing
Robertson-Walker ones (without any assumption on the fiber) is studied, under a global …

The focus of this paper is to characterize the Lorentzian manifolds equipped with a semi-
symmetric non-metric ρ-connection [briefly,(M,∇ ̃)]. The conditions for a Lorentzian manifold …

In this paper we study geodesic completeness of Riemannian doubly warped products and
Lorentzian doubly warped products. We give necessary conditions for generalized …

In this paper, we study Ricci-flat and Einstein–Lorentzian multiply warped products. We also
consider the case of having constant scalar curvatures for this class of warped products …

The curvature and Killing vector fields of a class of spacetimes generalizing Robertson-
Walker ones (without any assumption on the fiber) is widely studied. Such spacetimes …

In this paper, we first state covariant derivative formulas for multiply warped products and
consider the geodesic equations for these spaces. Then we state some basic facts about …

We address the problem of finding conditions under which a compact Lorentzian manifold is
geodesically complete, a property, which always holds for compact Riemannian manifolds. It …

We review geometrical properties of a static spacetime (M, g), including geodesic
completeness, causality, standard splittings, compact M, closed geodesics and geodesic …