Kinetics of interacting gravitational and electromagnetic perturbations in cosmological plasma

The system of Einstein-Maxwell equations and a kinetic equation with a model collision integral for the cosmological plasma is used to study the behavior of gravitational and electromagnetic perturbations in the radiation-dominated stage of expansion of the universe. It is shown that gravitational perturbations are capable of generating electromagnetic fields in the cosmological plasma.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 1, pp. 91–96, January, 1992.     

Transverse Wave Propagation in Relativistic Two-Fluid Plasmas around Schwarzschild-de Sitter Black Hole

We investigate transverse electromagnetic waves propagating in a plasma influenced by the gravitational field of the Schwarzschild-de Sitter black hole. Applying 3+1 spacetime split we derive the relativistic two-fluid equations to take account of gravitational effects due to the event horizon and describe the set of simultaneous linear equations for the perturbations. We use a local approximation to investigate the one-dimensional radial propagation of Alfvén and high frequency electromagnetic waves. We derive the dispersion relation for these waves and solve it for the wave number k numerically.     

Transverse Wave Propagation in Relativistic Two-Fluid Plasmas around Reissner–Nordström Black Hole

We investigate transverse electromagnetic waves propagating in a plasma influenced by the gravitational field of the Reissner–Nordström black hole. Applying 3+1 spacetime split we reformulate the relativistic two-fluid equations to take account of gravitational effects due to the event horizon and describe the set of simultaneous linear equations for the perturbations. Using a local approximation we investigate the one-dimensional radial propagation of Alfvén and high frequency electromagnetic waves. We derive the dispersion relation for these waves and solve it for the wave number k numerically.     

Transverse wave propagation in relativistic two-fluid plasmas around Reissner–Nordström–de Sitter black hole

The transverse electromagnetic waves propagating in a relativistic two-fluid plasma influenced by the gravitational field of the Reissner–Nordström–de Sitter black hole has been investigated exploiting “3 + 1” split of spacetime. Reformulating the two-fluid equations, the set of simultaneous linear equations for the perturbations have been derived. Using a local approximation, the one-dimensional radial propagation of Alfvén and high frequency electromagnetic waves are investigated. The dispersion relation for these waves is obtained and solved numerically for the wave number.     

Generation of longitudinal plasma oscillations by gravitational perturbations in an isotropic universe

The electric charge density induced by scalar gravitational perturbations in the lepton and radiation-dominated stages of the expansion of the universe is calculated. It is shown that the formation of clusters of matter is accompanied in the radiation-dominated stage by a build-up of positive charge in the central regions of the cluster. The charge-mass relation of the clusters is calculated.Translated from Izvestiya Vysshkikh Uchebnykh Zavedenii, Fizika, No. 5, pp. 52–57, May, 1986.     

The Rayleigh-Taylor instability and internal waves in quantum plasmas

Influence of quantum effects on the internal waves and the Rayleigh-Taylor instability in plasma is investigated. It is shown that quantum pressure always stabilizes the RT instability. The problem is solved both in the limit of short-wavelength perturbations and exactly for density profiles with layers of exponential stratification. In the case of stable stratification, quantum pressure modifies the dispersion relation of the inertial waves. Because of the quantum effects, the internal waves may propagate in the transverse direction, which was impossible in the classical case. A specific form of pure quantum internal waves is obtained, which do not require any external gravitational field.     

Kinetic theory of the generation of magnetic fields in the radiation-dominated stage of expansion of the universe

The system of linearized Einstein and Maxwell equations and a kinetic equation with model collision integral for the cosmological plasma are used to calculate the magnetic field generated by solenoidal perturbations in the radiation-dominated stage of expansion of the universe. The magnetic field is generated by two effects — the Harrison effect and a new effect due to kinetic processes. The second effect contributes to the magnetic field if solenoidal gravitational perturbations exist from the very beginning of the radiation-dominated stage.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 1, pp. 122–126, January, 1992.     

The anomalous resonance absorption of electromagnetic waves as a phenomenon of radiative damping

Summary The well-known anomalous absorption of transverse electromagnetic waves near the resonance point of a plasma surface is described as a phenomenon of radiative damping of waves. Reflections from a sharp plasma surface and from smoothly inhomogenous plasma are considered separately. It is shown that during the reflection ofE-waves from the surface of a smoothly bounded inhomogeneous plasma, radiative damping occurs in the reflecting point as a result of longitudinal plasma waves emission and it is also shown that anomalous absorption of electromagnetic waves in the long-wavelength limit is significant as well as in the short wavelength.     

Moving perturbations of the ionization in a field of strong electromagnetic waves

The perturbation of the ionization and of the electron temperature is considered in a plasma in a field of strong electromagnetic waves. It is shown that the intensified absorption of the waves in the region of their reflection leads to the appearance of the moving perturbations of the plasma ionization. The conditions governing the development of moving perturbations are determined along with their velocity and spatial structure. It is demonstrated that in a weakly inhomogeneous plasma such perturbations appear in the neighborhood of the reflection point of the waves and move toward the wave so as to cause perturbation. This leads to the generation of nondecaying nonlinear oscillations in the plasma. The frequency of the oscillations is determined, and it decreases with increasing absorbed power of the waves.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Radiofizika, Vol. 15, No. 1, pp. 11–18, January, 1972.The author is indebted to V. L. Ginzburg for his useful discussions.     

Joint behavior of longitudinal electromagnetic waves and scalar gravitational disturbances in the cosmological plasma with allowance for electron-photon collisions

The electric charge density induced by scalar gravitational perturbations in the radiation-dominated stage of the expansion of the universe is calculated on the basis of an investigation of the combined system of Einstein, Maxwell, and kinetic equations for a cosmological plasma with a model collision integral.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 2, pp. 97–100, February, 1992.     

Gravitational Wave Detection by Bounded Cold Electronic Plasma in a Long Pipe

We intend to propose an experimental sketch to detect gravitational waves (GW) directly, using an cold electronic plasma in a long pipe. By considering an cold electronic plasma in a long pipe, the Maxwell equations in 3+1 formalism will be invoked to relate gravitational waves to the perturbations of plasma particles. It will be shown that the impact of GW on cold electronic plasma causes disturbances on the paths of the electrons. Those electrons that absorb energy from GW will pass through the potential barrier at the end of the pipe. Therefore, crossing of some electrons over the barrier will imply the existence of the GW.     

Gravitational and electromagnetic signatures of accretion into a charged black hole

We present the derivation and the solutions to the coupled electromagnetic and gravitational perturbations with sources in a charged black hole background. We work in the so called ghost gauge and consider as source of the perturbations the infall of radial currents. In this way, we study a system in which it is provoked a response involving both, gravitational and electromagnetic waves, which allows us to analyze the dependence between them. We solve numerically the wave equations that describe both signals, characterize the waveforms and study the relation between the input parameters of the infalling matter with those of the gravitational and electromagnetic responses.     

Transverse wave propagation in relativistic two-fluid plasmas in de Sitter space

We investigate transverse electromagnetic waves propagating in a plasma near the horizon of the de Sitter space. Using the 3+1 formalism we derive the relativistic two-fluid equations to take account of the effects due to the horizon and describe the set of simultaneous linear equations for the perturbations. We use a local approximation to investigate the one-dimensional radial propagation of Alfvén and high frequency electromagnetic waves and solve the dispersion relation for these waves numerically.     

Stability of magnetopause boundary and generation of long period geomagnetic pulsations

The effect of irrotational electric field and tensorial plasma conductivity on the growth rate of Kelvin-Helmholtz instability has been investigated. It is shown that the presence of irrotational electric field alters the growth rate. The dependence of Pedersen conductivity on the growth rate has been shown. The Kelvin-Helmholtz perturbations generate a surface wave in the frozen-in plasma. The propagation of these waves gives rise to polarization of the transverse hydromagnetic pulsations. It is shown that the modified K-H spectrum would result in a corresponding change in polarization features of the hydromagnetic pulsations.     

Some High-Frequency Gravitational Waves Related to Exact Radiative Spacetimes

A formalism is introduced which may describe both standard linearized waves and gravitational waves in Isaacson's high-frequency limit. After emphasizing main differences between the two approximation techniques we generalize the Isaacson method to non-vacuum spacetimes. Then we present three large explicit classes of solutions for high-frequency gravitational waves in particular backgrounds. These involve non-expanding (plane, spherical or hyperbolical), cylindrical, and expanding (spherical) waves propagating in various universes which may contain a cosmological constant and electromagnetic field. Relations of high-frequency gravitational perturbations of these types to corresponding exact radiative spacetimes are described.     

Interaction between gravity and moving superconductors

We propose a unified phenomenological theory to investigate the interaction between arbitrarily moving superconductors and gravitational fields including the Newtonian gravity, gravitational waves, vector transverse gravitoelectric fields, and vector gravitomagnetic fields. In the limit of weak field and low velocity, the expressions for the induced electromagnetic and gravitational fields in the interior of a moving superconductor are obtained. The Meissner effect, London moment, DeWitt effect, effects of gravitational wave on a superconductor, and induced electric fields in the interior of a freely vibrating superconductor are recovered from these two expressions. We demonstrate that the weak equivalence principle is valid in superconductivity, that Newtonian gravity and gravitational waves will penetrate either a moving superconductor or a superconductor at rest, and that a superconductor at rest cannot shield either vector gravitomagnetic fields or vector transverse gravitoelectric fields.     

Gravitational Waves and Extra Dimensions: A Short Review *

We give a brief review on the recent development of gravitational waves in extra-dimensional theories of gravity. Studying extra-dimensional theories with gravitational waves provides a new way to constrain extra dimensions. After a flash look at the history of gravitational waves and a brief introduction to several major extra-dimensional theories, we focus on the sources and spectra of gravitational waves in extra-dimensional theories. It is shown that one can impose limits on the size of extra dimensions and the curvature of the universe by researching the propagations of gravitational waves and the corresponding electromagnetic waves. Since gravitational waves can propagate throughout the bulk, how the amplitude of gravitational waves decreases determines the number of extra dimensions for some models. In addition, we also briefly present some other characteristics of gravitational waves in extra-dimensional theories.     

Gravitational radiation of a plasma and transformation of electromagnetic waves into gravitational waves

The gravitational radiation accompanying propagation of a high-frequency electromagnetic wave within a plasma is considered. It is shown that if the electromagnetic wavelength is much greater than the Debye radius, the major contribution to gravitational radiation is produced by combination transformation with frequency change Δω=±w_L.     

Gravitational wave generation in power-law inflationary models

We investigate the generation of gravitational waves in power-law inflationary models. The energy spectrum of the gravitational waves is calculated using the method of continuous Bogoliubov coefficients. We show that, by looking at the interval of frequencies between 10⁻⁵ and 10⁵ Hz and also at the GHz range, important information can be obtained, both about the inflationary period itself and about the thermalization regime between the end of inflation and the beginning of the radiation-dominated era. We thus deem the development of gravitational wave detectors, covering the MHz/GHz range of frequencies, to be an important task for the future.     

Gravitational collapse with charge and small asymmetries. II. Interacting electromagnetic and gravitational perturbations

Paper I analyzed the evolution of nonspherical scalar-field perturbations of an electrically charged, collapsing star; this paper treats coupled electromagnetic and gravitational perturbations. It employs the results of recent detailed work in which coupled perturbations were studied in a gauge-invariant manner by using the Hamiltonian (Moncrief s) approach and the Newman-Penrose formalism, and the relations between the fundamental quantities of these two methods were obtained.It is shown that scalar-field perturbations are a prototype for coupled perturbations. The collapse produces a Reissner-Nordström black hole, and the perturbations are radiated away completely. Alll-pole parts of the perturbations of the metric and the electromagnetic field decay according to power laws; in the extreme case (e ² =M ²), the interaction causes the quadrupole perturbations to die out more slowly than the dipole perturbations.