We review spherical and inhomogeneous analytic solutions of the field equations of Einstein
and of scalar–tensor gravity, including Brans–Dicke theory, non-minimally (possibly …

We model the supermassive dark object M 8 7* as a Schwarzschild lens and study the
variations in tangential, radial, and total (the product of tangential and radial) magnifications …

We model massive dark objects in galactic nuclei as spherically symmetric static naked
singularities in the Einstein massless scalar field theory and study the resulting gravitational …

A static and circularly symmetric lens characterized by mass and scalar charge parameters
is constructed. For the small values of the scalar charge to the mass ratio, the gravitational …

Gravitational lensing of luminous matter that surrounds a black hole or some other
sufficiently compact object produces an infinite sequence of images. Besides the direct (or …

We model massive dark objects at centers of many galaxies as Schwarzschild black hole
lenses and study gravitational lensing by them in detail. We show that the ratio of mass of a …

We model the massive dark object at the center of the Galaxy as a Schwarzschild black hole
as well as Janis-Newman-Winicour naked singularities, characterized by the mass and …

We investigate which Jordan frame F (R) gravity can describe a type IV singular bouncing
cosmological evolution, with special emphasis given near the point at which the type IV …

In this paper, we study the deflection of light by a class of phantom black hole and wormhole
solutions in the weak limit approximation. More specifically, in the first part of this work we …

It is shown that for a general nonstatic spherically symmetric metric of the Kerr-Schild class
several energy-momentum complexes give the same energy distribution as in the Penrose …