General relativistic galvano-gravitomagnetic effect in current carrying conductors

The analogy between general relativity and electromagnetism suggests that there is a new galvano-gravitomagnetic effect, which is the gravitational analog of the Hall effect and takes place when a current carrying conductor is placed in a gravitomagnetic field. In connection with this galvano-gravitomagnetic effect, we explore the possibility of using current carrying conductors for detecting the gravitomagnetic field of the Earth.     

The dual curvature tensors and dynamics of gravitomagnetic matter

Gravitomagnetic charge that can also be referred to as the dual mass or magnetic mass is the topological charge in gravity theory. A gravitomagnetic monopole at rest can produce a stationary gravitomagnetic field. Due to the topological nature of gravitomagnetic charge, the metric of spacetime where the gravitomagnetic matter is present will be nonanalytic. In this paper both the dual curvature tensors (which can characterize the dynamics of gravitational charge/monopoles) and the antisymmetric gravitational field equation of gravitomagnetic matter are presented. We consider and discuss the mathematical formulation and physical properties of the dual curvature tensors and scalar, antisymmetric source tensors, dual spin connection (including the low‐motion weak‐field approximation), dual vierbein field as well as dual current densities of gravitomagnetic charge. It is shown that the dynamics of gravitomagnetic charge can be founded within the framework of the above dual quantities. In addition, the duality relationship in the dynamical theories between the gravitomagnetic charge (dual mass) and the gravitoelectric charge (mass) is also taken into account in the present paper.     

Test of the gravitomagnetic field via laser-ranged satellites

We describe a new experiment to measure the gravitomagnetic field of the Earth. This field, a consequence of the general relativistic formulation of Mach's principle (WEM—Wheeler-Einstein-Mach principle), has never been detected. The idea is to measure the Lense-Thirring precession of the nodal lines of two laser-ranged satellites with supplementary inclinations. In this way it is possible to separate the relativistic nodal precession from the classical nodal precession due to the multipole moments of the Earth.     

Relativistic thermoelectromagnetic gravitational effects in normal conductors and superconductors

The general principles needed to compute the effect of a stationary gravitational field on the thermoelectric phenomena in normal conductors and superconductors are formulated from a general relativistic point of view. These principles are then applied to a variety of devices which can, in principle, measure the gravitational field. Generalizations of the Thomson, Seebeck, Peltier and Josephson effects and the London moment are obtained.     

Gravitational Analogues, Geometric Effects and Gravitomagnetic Charge

This essay discusses some geometric effects associated with gravitomagnetic fields and gravitomagnetic charge as well as the gravity theory of the latter. Gravitomagnetic charge is the duality of gravitoelectric charge (mass) and is therefore also termed the dual mass which represents the topological property of gravitation. The field equation of gravitomagnetic matter is suggested and a static spherically symmetric solution of this equation is offered. A possible explanation of the anomalous acceleration acting on Pioneer spacecrafts are briefly proposed.     

Classical Gravitational Interactions and Gravitational Lorentz Force

In quantum gauge theory of gravity, the gravitational field is represented by gravitational gauge field. The field strength of gravitational gauge field has both gravitoelectric component and gravitomagnetic component. In classical level, gauge theory of gravity gives classical Newtonian gravitational interactions in a relativistic form. Besides, it gives gravitational Lorentz force, which is the gravitational force on a moving object in gravitomagnetic field. The direction of gravitational Lorentz force is not the same as that of classical gravitational Newtonian force. Effects of gravitational Lorentz force should be detectable, and these effects can be used to discriminate gravitomagnetic field from ordinary electromagnetic magnetic field.     

Classical Gravitational Interactions and Gravitational Lorentz Force

In quantum gauge theory of gravity, the gravitational field is represented by gravitational gauge field.The field strength of gravitational gauge field has both gravitoelectric component and gravitomagnetic component. In classical level, gauge theory of gravity gives classical Newtonian gravitational interactions in a relativistic form. Besides,it gives gravitational Lorentz force, which is the gravitational force on a moving object in gravitomagnetic field The direction of gravitational Lorentz force is not the same as that of classical gravitational Newtonian force. Effects of gravitational Lorentz force should be detectable, and these effects can be used to discriminate gravitomagnetic field from ordinary electromagnetic magnetic field.     

交错网格下MHD相容守恒格式的发展

在低磁场雷诺数条件下,基于电势泊松方程,发展了交错网格下可以精确计算电流和洛伦兹力(电磁力)的相容守恒格式。采用压力为变量的原始变量法求解不可压缩Navier-Stokes方程,所计算的电流满足电荷守恒定律,所计算的电磁力满足动量守恒定律。对金属流体在Hartmann数50~5000范围内验证了格式的精确性。交错网格下相容守恒格式的发展为后续MHD稳定性分析、湍流的大涡模拟及直接数值模拟提供很好的选择。     

Macroscopic space charge field in disturbed quasineutral plasma

A method of calculation of the electric field intensity in a quasineutral plasma homogeneity of which is disturbed is found for the case when the problem can be formulated as one-dimensional. The general formula (19) comprising the Ohm's law, ambipolar approximation and higher approximations of the space charge electric field intensity, expressed in terms of deviationn ₊ in ion density and its derivatives, is found and the values of the errors of these approximations are derived. Numerical calculations for the sinusoidal as well as for the Gaussian form of the perturbation in the ion concentration are carried out.     

Turbulent diamagnetism in flowing liquid sodium

The nature of Ohm's law is examined in a turbulent flow of liquid sodium. A magnetic field is applied to the flowing sodium, and the resulting magnetic field is measured. The mean velocity field of the sodium is also measured in an identical-scale water model of the experiment. These two fields are used to determine the terms in Ohm's law, indicating the presence of currents driven by a turbulent electromotive force. These currents result in a diamagnetic effect, generating magnetic field in opposition to the dominant fields of the experiment. The magnitude of the fluctuation-driven magnetic field is comparable to that of the field induced by the sodium's mean flow.     

A new approach to studying local gravitomagnetic effects on a superconductor

In this paper we introduce gravitomagnetic field equations into the investigation of gravitomagnetic effects on a superconductor. We point out that in the absence of an applied magnetic field, an applied gravitomagnetic field will induce twin currents, gravitational and electric supercurrents. The latter will create a magnetic field. The slightly modified Josephson, London, and London-type gravitomagnetic equations are obtained. Some applications of these equations are discussed.     

DC conduction processes and electrical parameters of the organic semiconducting zinc phthalocyanine, ZnPc, thin films

Electronic conduction in thermally evaporated thin films of organic semiconductor zinc phthalocyanine (ZnPc) has been investigated in a broad temperature range using gold Ohmic contacts. Electronic conduction by charge carrier hopping was dominated at low temperatures and for all applied voltages. At higher temperatures and at voltages just below 2 V conduction was found to obey Ohm's law, while at higher voltages space-charge-limited conduction (SCLC) was the dominated mechanism, which was controlled by hole-trapping states distributed exponentially within the band gap.In freshly prepared samples adsorbed oxygen was responsible for lower hole mobility and higher charge carrier concentrations. Prolonged heating of ZnPc films at 425 K resulted in lower defect state density, and thus reduced trap concentration and higher charge carrier mobility.     

Generalized isothermal models with strange equation of state

We consider the linear equation of state for matter distributions that may be applied to strange stars with quark matter. In our general approach the compact relativistic body allows for anisotropic pressures in the presence of the electromagnetic field. New exact solutions are found to the Einstein-Maxwell system. A particular case is shown to be regular at the stellar centre. In the isotropic limit we regain the general relativistic isothermal Universe. We show that the mass corresponds to the values obtained previously for quark stars when anisotropy and charge are present.      

On the interaction of mesoscopic quantum systems with gravity

We review the different aspects of the interaction of mesoscopic quantum systems with gravitational fields. We first discuss briefly the foundations of general relativity and quantum mechanics. Then, we consider the non‐relativistic expansions of the Klein‐Gordon and Dirac equations in the post‐Newtonian approximation. After a short overview of classical gravitational waves, we discuss two proposed interaction mechanisms: (i) the use of quantum fluids as generator and/or detector of gravitational waves in the laboratory, and (ii) the inclusion of gravitomagnetic fields in the study of the properties of rotating superconductors. The foundations of the proposed experiments are explained and evaluated.     

General relativistic measurements with satellite laser ranging, lunar laser ranging and very long baseline interferometry

Summary After a brief discussion on the experimental tests of general relativity, we describe three new measurements of Einstein theory. The first, already performed, is the test of the De Sitter or geodetic effect, for the Earth-Moon system. The second will be realized with the launch of the laser ranged satellite, LAGEOS III, and will test the existence of the, never measured, gravitomagnetic field. The third, currently being performed, is the measurement of the LAGEOS relativistic perigee advance. To speed up publication, the proofs were not sent to the authors and were supervised by the Scientific Committee.     

The gravitomagnetic clock effect and its possible observation

The general relativistic gravitomagnetic clock effect involves a coupling between the orbital motion of a test particle and the rotation of the central mass and results in a difference in the proper periods of two counter–revolving satellites. It is shown that at ??(c^‐2) this effect has a simple analogue in the electromagnetic case. Moreover, in view of a possible measurement of the clock effect in the gravitational field of the Earth, we investigate the influence of some classical perturbing forces of the terrestrial space environment on the orbital motion of test bodies along opposite trajectories.     

Charge and Heat Transport in Polycrystalline Metallic Nanostructures

Metals are typically good conductors in which the abilities to transport charge and to transport heat can be related through the Wiedemann-Franz law. Here we report on an abnormal charge and heat transport in polycrystalline metallic nanostructures in which the ability to transport charge is weakened more obviously than that to transport heat. We attribute it to the influence of the internal grain boundaries and have formulated a novel relation to predict the thermal conductivity. The Wiedemann-Franz law is then modified to account for the influence of the grain boundaries on the charge and heat transport with the predictions now agreeing well with the measured results.     

On properties of vacuum axially symmetric spacetime of gravitomagnetic monopole in cylindrical coordinates

We investigate general relativistic effects associated with the gravitomagnetic monopole moment of a gravitational source through the analysis of the motion of test particles and electromagnetic fields distribution in the spacetime around the nonrotating cylindrical NUT source. We consider the circular motion of test particles in the NUT spacetime, their characteristics and the dependence of the effective potential on the radial coordinate for the different values of the NUT parameter and orbital momentum of test particles. It is shown that the bounds of stability for circular orbits are displaced toward the event horizon with the growth of the monopole moment of the NUT object. In addition, we obtain exact analytical solutions of the Maxwell equations for magnetized and charged cylindrical NUT stars.     

Spin waves in the Fermi liquid of quasi-two-dimensional conductors

The spin waves in layered conductors with a charge carrier dispersion law that admits of open trajectories in momentum space are investigated in terms of the Fermi-liquid theory.