We have derived the differential equation governing the evolution of the photon sphere for
dynamical black hole spacetimes with or without spherical symmetry. Numerical solution of …

It was shown that a standard ring of light can be imagined outside the event horizon for
stationary rotating four-dimensional black holes with axial symmetry using the topological …

In the present paper we prove a uniqueness theorem for the static and asymptotically flat
solutions to the Einstein-scalar field equations which possess a photon sphere. We show …

It has been shown in the literature that the event horizon of an asymptotically flat extremal
Reissner–Nordström black hole is also a stable photon sphere. We further clarify this …

In this article we extend a recent theorem proven by Hod [Upper bound on the radii of black-
hole photon spheres, Phys. Lett. B 727, 345 (2013)] to n-dimensional Einstein and Einstein …

We consider the problem of uniqueness of static and asymptotically flat Einstein–Maxwell
spacetimes with a photon sphere P 3. We are using a naturally modified definition of a …

We consider the problem for the classification of static and asymptotically flat Einstein-
Maxwell-dilaton spacetimes with a photon sphere. It is first proven that the photon spheres in …

In this work, we consider electromagnetic dynamics in Randall-Sundrum branes. It is derived
from a family of four-dimensional spacetimes compatible with Randall-Sundrum brane …

In this work, we present an extensive dynamical analysis of the null geodesics in the
spacetimes proposed by Casadio, Fabbri, and Mazzacurati (CFM), which model black holes …

We propose a gauge-invariant model of propagating torsion which couples to the Maxwell
field and to charged particles. As a result, we have an Abelian gauge-invariant action …