Related papers: A charged rotating cylindrical shell
The closed-universe recollapse conjecture is studied for the spherically symmetric spacetimes. It is proven that there exists an upper bound to the lengths of timelike curves in any Tolman spacetime that possesses $S^3$ Cauchy surfaces and…
We provide a 2-fluid immiscible matter source that supplies fuel to construct wormhole spacetime. The exact wormhole solutions are found in the model having, besides real matter or ordinary matter, some quintessence matter along with charge…
In this study, the particle motion around the naked singularity and black hole of Kerr-Newman spacetime is investigated with a special attention on the closed timelike orbits. It is found that both in the naked singularity (NS) and in black…
We study the issue of description of spinning particle dynamics by means of recently proposed world sheet concept. A model of irreducible spinning particle in the $3d$ Minkowski space with two gauge symmetries is considered. The classical…
Casimir-Polder potential is investigated for a polarizable microparticle in the geometry of a straight cosmic string with a metallic cylindrical shell. The electromagnetic field Green tensor is evaluated on the imaginary frequency axis. The…
In this study, the geodesic motion of a test particle along with its confinement is investigated within Cylindrically Symmetric Wormhole spacetime admitting to Closed Timelike Curves. The confinement of particles with or without angular…
A new version of the geometry inside a black hole is proposed, on the grounds of an idea given by Doran et al. The spacetime is still time dependent and is a solution of Einstein's equations with a stress tensor corresponding to an…
Effective models inspired by loop quantum gravity typically resolve the central singularity by replacing it with a bounce of the matter density in the Planckian regime. In the specific model analyzed here, this bounce is generally followed…
We give a perturbative analysis for an infinitesimally thin cylindrical shell composed of counter rotating collisionless particles, originally devised by Apostolatos and Thorne. They found a static solution of the shell and concluded by…
We present a maximally symmetric vacuum spacetime, which is locally isometric anti- de Sitter, admitting closed timelike curves appear after a definite instant of time i.e., a time-machine spacetime. The spacetime is regular, free-from…
Integrability conditions arising from general irrotational fluid-flow considerations of a universe dominated by cosmic dark fluids will be investigated under special assumptions on the nature of the spacetime shear. Special emphasis will be…
Slowly rotating collapsing spherical shells have flat spaces inside and the inertial frames there rotate at omega_s(t) relative to infinity. As first shown by Lindblom & Brill the inertial axes within the shell rotate rigidly without time…
We consider gravity in 2+1 dimensions in presence of extended stationary sources with rotational symmetry. We prove by direct use of Einstein's equations that if i) the energy momentum tensor satisfies the weak energy condition, ii) the…
Relativistic equation of state and velocity comparable with the speed of light are included in consideration of a superfluid rotating in a cylindrical container. Minimizing the free energy, we derive the equation of motion. It admits an…
Starting from Israel equations for the spherically symmetric thin shells we introduce the effective potential and show how it can be used in constructing, without further thorough investigation, the corresponding Carter-Penrose diagrams…
We build extended sources for the Reissner-Nordstr\"{o}m metric. Our models describe a neutral perfect fluid core bounded by a charged thin shell, and feature everywhere positive rest mass density and everywhere non-negative active…
The method of an effective potential is used to investigate the possible types of evolution of vacuum shells in the Friedman-Schwarzschild world. Such shells are assumed to emerge during phase transitions in the early Universe. The possible…
We present a spinning black hole solution in $d$ dimensions with a maximal number of rotation parameters in the context of the Einstein-Maxwell-Dilaton theory. An interesting feature of such a solution is that it accommodates Lifshitz black…
We consider stationary rotating cylindrically symmetric dust spacetimes. We first show that the Maitra spacetime is the unique non-rigidly (non null shear scalar) rotating solution with a regular axis and that is the most general one of the…
The gravitational collapse of a thick cylindrical shell of dust matter is investigated. It is found that a spacetime singularity forms on the symmetry axis and that it is necessarily naked, i.e., observable in principle. We propose a…