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Valentin D. Gladush

Publications and source records attributed to Valentin D. Gladush.

10 recordsLinked to original sources
arXiv2013

On the effective actions for the spherical charged dust shell in General Relativity

A simple and direct, based on the equations of motion, derivation of the variational principle and effective actions for a spherical charged dust shell in general relativity is offered. This principle is based on the relativistic version of the DÆAlembert principle of virtual displacements and leads to the effective actions for the shell, which describe the shell from the point of view of the exterior or interior stationary observers. Herewith, sides of the shell are considered independently, in the coordinates of the interior or exterior region of the shell. Canonical variables for a charged dust shell are built. It is shown that the conditions of isometry of the sides of the shell lead to the Hamiltonian constraint on these interior and exterior dynamical systems. Special cases of the ôhollowö and ôscreeningö shells are briefly considered, as well as a family of the concentric charged dust shells.

gr-qc↗
arXiv2013

Stable and decaying bound states on the naked Reissner-Nordström background

We present a quantum mechanical study of the bound states of a neutral scalar particle on the curved background described by the Reissner-Nordström (RN) spacetime that corresponds to a naked singularity. We show that there occurs both the metastable, \textit{i.e.} decaying bound states and the stable ones. The corresponding energy spectra are calculated in the leading WKB approximation and the comparison with the RN black hole quasinormal mode spectrum is made. The metastable bound states on the naked singularity background turn out to be more long-living than the quasinormal modes for the black hole with the same mass.

gr-qc↗
arXiv2011

The model of dark galactic halo based on equilibrium distribution function

The model of galactic halo as a system of the collisionless small neutral particles from the standpoint of kinetic theory is considered. For the equilibrium system with the use of Maxwell-Boltzmann distribution we obtained results which explain the observed flat rotation curve. These results practically coincide with the results of equilibrium spherical gas cloud model in Newtonian gravitation with linear state equation.

gr-qc↗
arXiv2011

Classification for the radial component of particles motion in the field of a super-extremely charged object

A method for investigation of neutral test particles motion with the angular momentum L in the Reissner-Nordström field of a super-extremely charged object with mass M and charge Q > M is proposed. The problem of classifying the radial component of motion is reduced to working up a classification for "effective" potential types and subsequent consideration of trajectories for each of these types.

gr-qc↗
arXiv2011

Naked Reissner-Nordström singularity and quasiclassical bound states

The bound-state problem for an uncharged massive scalar particle in the field of a naked Reissner-Nordström singularity is approached by means of the quasiclassical Bohr-Sommerfeld quantization. An approximate analytical expression for the energy levels of the system is derived. It is shown that in order to obtain non-vanishing binding energies the masses of both the central object and the particle should be comparable with the Planck mass.

gr-qc↗
arXiv2010

Some peculiarities of motion of neutral and charged test particles in the field of a spherically symmetric charged object in General Relativity

We propose the method of investigation of radial motions for charged and neutral test particles in the Reissner-Nordström field by means of mass potential. In this context we analyze special features of interaction of charges and their motions in General Relativity and construct the radial motion classification. For test particles and a central source with charges $q$ and $Q$, respectively, the conditions of attraction (when $qQ>0$) and repulsion (when $qQ<0$) are obtained. The conditions of motionless test particle states with respect to the central source are investigated and, in addition, stability conditions for such static equilibrium states are found. It is shown that stable states are possible only for the bound states of weakly charged particles in the field of a naked singularity. Frequencies of small oscillations of test particles near their equilibrium positions are also found.

gr-qc↗
arXiv2005

A vacuum-like configuration in General Relativity as a manifestation of a Lorentz-invariant mode of five-dimensional gravity

A Lorentz-invariant cosmological model is constructed within the framework of five-dimensional gravity. The five-dimensional theorem which is analogical to the generalized Birkhoff theorem is proved, that corresponds to the Kaluza's ``cylinder condition''. The five-dimensional vacuum Einstein equations have an integral of motion corresponding to this symmetry, the integral of motion is similar to the mass function in general relativity (GR). Space closure with respect to the extra dimensionality follows from the requirement of the absence of a conical singularity. Thus, the Kaluza-Klein (KK) model is realized dynamically as a Lorentz-invariant mode of five-dimensional general relativity. After the dimensional reduction and conformal mapping the model is reduced to the GR configuration. It contains a scalar field with a vanishing conformally invariant energy-momentum tensor on the flat space-time background. This zero mode can be interpreted as a vacuum configuration in GR. As a result the vacuum-like configuration in GR can be considered as a manifestation of the Lorentz-invariant empty five-dimensional space.

gr-qc↗
arXiv2001

Five-dimensional general relativity and Kaluza-Klein theory

We consider 5D spaces which admit the most symmetric 3D subspaces. 5D vacuum Einstein equations are constructed and 5D analog of the mass function is found. The corresponding conservation law leads to 5D analog of Birkhoff's theorem. Hence the cylinder condition is dynamically implemented for the considered spaces. For some obtained metrics a period of space with respect to the fifth coordinate was found. The problem of the dynamical degrees of freedom of the fields system obtained in the process of dimensional reduction is discussed, and the problem of their interpretation is considered. One can think that the parametrization of the scalar field and 4D metric leading to the conformally invariant 4D theory for interacting gravitational and scalar fields is most natural and adequate.

gr-qc↗