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Analysis of Modeling the Influence of Electromagnetic Fields Radiated by Industrial Static Converters and Impacts on Operators Using Maxwell’s Equations
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作者 Anthony Bassesuka Sandoka Nzao Tuka Biaba Samuel Garcia +2 位作者 Obed Bitala Arsène Kasereka Kibwana Emmanuel Ndaye Kibuayi 《Open Journal of Applied Sciences》 2024年第8期2320-2350,共31页
The study of Electromagnetic Compatibility is essential to ensure the harmonious operation of electronic equipment in a shared environment. The basic principles of Electromagnetic Compatibility focus on the ability of... The study of Electromagnetic Compatibility is essential to ensure the harmonious operation of electronic equipment in a shared environment. The basic principles of Electromagnetic Compatibility focus on the ability of devices to withstand electromagnetic disturbances and not produce disturbances that could affect other systems. Imperceptible in most work situations, electromagnetic fields can, beyond certain thresholds, have effects on human health. The objective of the present article is focused on the modeling analysis of the influence of geometric parameters of industrial static converters radiated electromagnetic fields using Maxwell’s equations. To do this we used the analytical formalism for calculating the electromagnetic field emitted by a filiform conductor, to model the electromagnetic radiation of this device in the spatio-temporal domain. The interactions of electromagnetic waves with human bodies are complex and depend on several factors linked to the characteristics of the incident wave. To model these interactions, we implemented the physical laws of electromagnetic wave propagation based on Maxwell’s and bio-heat equations to obtain consistent results. These obtained models allowed us to evaluate the spatial profile of induced current and temperature of biological tissue during exposure to electromagnetic waves generated by this system. The simulation 2D results obtained from computer tools show that the temperature variation and current induced by the electromagnetic field can have a very significant influence on the life of biological tissue. The paper provides a comprehensive analysis using advanced mathematical models to evaluate the influence of electromagnetic fields. The findings have direct implications for workplace safety, potentially influencing standards and regulations concerning electromagnetic exposure in industrial settings. 展开更多
关键词 MODELING Electromagnetic field Power Converters Geometric Parameters Biological Tissue Maxwell equation Bio-Heat equation Thermal Model
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Space-Energy Duality Generalized 4-Index Einstein Field Equation
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作者 Mahgoub A. Salih 《International Journal of Astronomy and Astrophysics》 2023年第4期281-297,共17页
The introduction of a new concept of space-energy duality serves to extend the applicability of the Einstein field equation in the context of a 4-index framework. The utilization of the Weyl tensor enables the derivat... The introduction of a new concept of space-energy duality serves to extend the applicability of the Einstein field equation in the context of a 4-index framework. The utilization of the Weyl tensor enables the derivation of Einstein’s equations in the 4-index format. Additionally, a two-index field equation is presented, comprising a conventional Einstein field equation and a trace-free Einstein equation. Notably, the cosmological constant is associated with a novel concept that facilitates the encoding of space and energy information, thereby enabling the recognition of mutual interactions between space and energy in the presence of gravitational forces, as dictated by Einstein’s field equations (EFE) and Trace-Free Einstein Equation (TFE). 展开更多
关键词 einstein field equation Trace-Free einstein equation 4-Index Cosmological Constant
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The Maxwell-Heaviside Equations Explained by the Theory of Informatons
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作者 Antoine Acke 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2024年第3期1003-1016,共14页
In the articles “Newtons Law of Universal Gravitation Explained by the Theory of Informatons” and “The Gravitational Interaction between Moving Mass Particles Explained by the Theory of Informatons” the gravitatio... In the articles “Newtons Law of Universal Gravitation Explained by the Theory of Informatons” and “The Gravitational Interaction between Moving Mass Particles Explained by the Theory of Informatons” the gravitational interaction has been explained by the hypothesis that information carried by informatons is the substance of gravitational fields, i.e. the medium that the interaction in question makes possible. From the idea that “information carried by informatons” is its substance, it has been deduced that—on the macroscopic level—a gravitational field manifests itself as a dual entity, always having a field- and an induction component (Egand Bg) simultaneously created by their common sources. In this article we will mathematically deduce the Maxwell-Heaviside equations from the kinematics of the informatons. These relations describe on the macroscopic level how a gravitational field (Eg, Bg) is generated by whether or not moving masses and how spatial and temporal changes of Egand Bgare related. We show that there is no causal link between Egand Bg. 展开更多
关键词 GRAVITY Gravitational field Maxwell equations Informatons
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Diffusion Equations of the Electric Charges and Magnetic Flux
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作者 Salama Abdelhady Mohamed S. Abdelhady 《Journal of Electromagnetic Analysis and Applications》 2024年第5期69-83,共15页
Innovative definitions of the electric and magnetic diffusivities through conducting mediums and innovative diffusion equations of the electric charges and magnetic flux are verified in this article. Such innovations ... Innovative definitions of the electric and magnetic diffusivities through conducting mediums and innovative diffusion equations of the electric charges and magnetic flux are verified in this article. Such innovations depend on the analogy of the governing laws of diffusion of the thermal, electrical, and magnetic energies and newly defined natures of the electric charges and magnetic flux as energy, or as electromagnetic waves, that have electric and magnetic potentials. The introduced diffusion equations of the electric charges and magnetic flux involve Laplacian operator and the introduced diffusivities. Both equations are applied to determine the electric and magnetic fields in conductors as the heat diffusion equation which is applied to determine the thermal field in steady and unsteady heat diffusion conditions. The use of electric networks for experimental modeling of thermal networks represents sufficient proof of similarity of the diffusion equations of both fields. By analysis of the diffusion phenomena of the three considered modes of energy transfer;the rates of flow of these energies are found to be directly proportional to the gradient of their volumetric concentration, or density, and the proportionality constants in such relations are the diffusivity of each energy. Such analysis leads also to find proportionality relations between the potentials of such energies and their volumetric concentrations. Validity of the introduced diffusion equations is verified by correspondence their solutions to the measurement results of the electric and magnetic fields in microwave ovens. 展开更多
关键词 Diffusion Coefficient Diffusion equation Electric Charge Magnetic Flux Electromagnetic Waves Electric field Magnetic field
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How Classical, Quantum-Mechanical, and Relativistic Wave and Field Equations Are Uniformly Generated by Velocity-Field Divergence Equations
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作者 Frank Blume 《Journal of Applied Mathematics and Physics》 2023年第9期2739-2764,共26页
We expand previously established results concerning the uniform representability of classical and relativistic gravitational field equations by means of velocity-field divergence equations by demonstrating that conser... We expand previously established results concerning the uniform representability of classical and relativistic gravitational field equations by means of velocity-field divergence equations by demonstrating that conservation equations for (probability) density functions give rise to velocity-field divergence equations the solutions of which generate—by way of superposition—the totality of solutions of various well-known classical and quantum-mechanical wave equations. 展开更多
关键词 Uniform Representability Gravitational field equations Velocity-field Divergence equations Conservation equations Wave equations
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High-order field theory and a weak Euler–Lagrange–Barut equation for classical relativistic particle-field systems
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作者 范培锋 陈强 +1 位作者 肖建元 于治 《Plasma Science and Technology》 SCIE EI CAS CSCD 2023年第11期42-54,共13页
In both quantum and classical field systems,conservation laws such as the conservation of energy and momentum are widely regarded as fundamental properties.A broadly accepted approach to deriving conservation laws is ... In both quantum and classical field systems,conservation laws such as the conservation of energy and momentum are widely regarded as fundamental properties.A broadly accepted approach to deriving conservation laws is built using Noether's method.However,this procedure is still unclear for relativistic particle-field systems where particles are regarded as classical world lines.In the present study,we establish a general manifestly covariant or geometric field theory for classical relativistic particle-field systems.In contrast to quantum systems,where particles are viewed as quantum fields,classical relativistic particle-field systems present specific challenges.These challenges arise from two sides.The first comes from the mass-shell constraint.To deal with the mass-shell constraint,the Euler–Lagrange–Barut(ELB)equation is used to determine the particle's world lines in the four-dimensional(4D)Minkowski space.Besides,the infinitesimal criterion,which is a differential equation in formal field theory,is reconstructed by an integro-differential form.The other difficulty is that fields and particles depend on heterogeneous manifolds.To overcome this challenge,we propose using a weak version of the ELB equation that allows us to connect local conservation laws and continuous symmetries in classical relativistic particle-field systems.By applying a weak ELB equation to classical relativistic particle-field systems,we can systematically derive local conservation laws by examining the underlying symmetries of the system.Our proposed approach provides a new perspective on understanding conservation laws in classical relativistic particle-field systems. 展开更多
关键词 high-order field theory weak Euler-Lagrange-Barut equation infinitesimal criterion of symmetric condition Noether's theorem geometric conservation laws
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On Quasi-Einstein Field Equation
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作者 赵培标 杨孝平 《Northeastern Mathematical Journal》 CSCD 2005年第4期411-420,共10页
In this paper some properties of a symmetric tensor field T(X,Y) = g(A(X), Y) on a Riemannian manifold (M, g) without boundary which satisfies the S quasi-Einstein equation Rij-S/2gij=Tij+bξiξj are given. ... In this paper some properties of a symmetric tensor field T(X,Y) = g(A(X), Y) on a Riemannian manifold (M, g) without boundary which satisfies the S quasi-Einstein equation Rij-S/2gij=Tij+bξiξj are given. The necessary and sufficient conditions for this tensor to satisfy the quasi-Einstein equation are also obtained. 展开更多
关键词 einstein field equation quasi-einstein field equation Minkowski space Parallel field gravitational field “Ricci” symmetric tensor Lagrange equation
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On certain new exact solutions of the Einstein equations for axisymmetric rotating fields
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作者 Lakhveer Kaur R.K.Gupta 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第10期73-78,共6页
We investigate the Einstein field equations corresponding to the Weyl-Lewis-Papapetrou form for an axisymmetric rotating field by using the classical symmetry method. Using the invafiance group properties of the gover... We investigate the Einstein field equations corresponding to the Weyl-Lewis-Papapetrou form for an axisymmetric rotating field by using the classical symmetry method. Using the invafiance group properties of the governing system of partial differential equations (PDEs) and admitting a Lie group of point transformations with commuting infinitesimal generators, we obtain exact solutions to the system of PDEs describing the Einstein field equations. Some appropriate canonical variables are characterized that transform the equations at hand to an equivalent system of ordinary differential equations and some physically important analytic solutions of field equations are constructed. Also, the class of axially symmetric solutions of Einstein field equations including the Papapetrou solution as a particular case has been found. 展开更多
关键词 einstein equations symmetry analysis exact solutions
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Time-Machine Solutions of Einstein's Equations with Electromagnetic Field
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作者 沈明 孙庆有 《Communications in Theoretical Physics》 SCIE CAS CSCD 2011年第1期69-71,共3页
In this paper we investigate the time-machine problem in the electromagnetic field. Based on a metric which is a more general form of Ori's, we solve the Einstein's equations with the energy-momentum tensors for ele... In this paper we investigate the time-machine problem in the electromagnetic field. Based on a metric which is a more general form of Ori's, we solve the Einstein's equations with the energy-momentum tensors for electromagnetic field, and construct the time-machine solutions, which solve the time machine problem in electromagnetic field. 展开更多
关键词 time-machine solutions closed timelike curves einstein's equations energy-momentum tensor electromagnetic field energy conditions
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Bach-Einstein Gravitational Field Equations as a Perturbation of Einstein Gravitational Field Equations
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作者 Fathy Ibrahim Abdel-Bassier Ahmed Fouad Abdel-Wahab Fayrouz Mostafa Abdel-Maboud 《Applied Mathematics》 2022年第12期1022-1032,共11页
The Bach equations are a version of higher-order gravitational field equations, exactly they are of fourth-order. In 4-dimensions the Bach-Einstein gravitational field equations are treated here as a perturbation of E... The Bach equations are a version of higher-order gravitational field equations, exactly they are of fourth-order. In 4-dimensions the Bach-Einstein gravitational field equations are treated here as a perturbation of Einstein’s gravity. An approximate inversion formula is derived which admits a comparison of the two field theories. An application to these theories is given where the gravitational Lagrangian is expressed linearly in terms of R, R<sup>2</sup>, |Ric|<sup>2</sup>, where the Ricci tensor Ric = R<sub>αβ</sub>dx<sup>α</sup>dx<sup>β</sup> is inserted in some formulas which are of geometrical or physical importance, such as;Raychaudhuri equation and Tolman’s formula. 展开更多
关键词 Gravitational Theory Higher Order Gravity Buchdahl’s Formula Bach-einstein Gravitational field equations Raychaudhuri equation Tolman’s Formula
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New exact solutions of the Einstein-Maxwell equations for magnetostatic fields
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作者 Nisha Goyal R.K.Gupta 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第9期103-108,共6页
The symmetry reduction method based on the Frechet derivative of differential operators is applied to investigate symmetries of the Einstein-Maxwell field equations for magnetostatic fields, which is a coupled system ... The symmetry reduction method based on the Frechet derivative of differential operators is applied to investigate symmetries of the Einstein-Maxwell field equations for magnetostatic fields, which is a coupled system of nonlinear partial differential equations of the second order. The technique yields invariant transformations that reduce the given system of partial differential equations to a system of nonlinear ordinary differential equations. Some of the reduced systems are further studied to obtain the exact solutions. 展开更多
关键词 einstein-Maxwell equations symmetry reduction method exact solutions
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A Global Solution of the Einstein-Maxwell Field Equations for Rotating Charged Matter
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作者 Andreas Georgiou 《Journal of Modern Physics》 2012年第9期1301-1310,共10页
A stationary axially symmetric exterior electrovacuum solution of the Einstein-Maxwell field equations was obtained. An interior solution for rotating charged dust with vanishing Lorentz force was also obtained. The t... A stationary axially symmetric exterior electrovacuum solution of the Einstein-Maxwell field equations was obtained. An interior solution for rotating charged dust with vanishing Lorentz force was also obtained. The two spacetimes are separated by a boundary which is a surface layer with surface stress-energy tensor and surface electric 4-current. The layer is the spherical surface bounding the charged matter. It was further shown, that all the exterior physical quantities vanished at the asymptotic spatial infinity where spacetime was shown to be flat. There are two different sets of junction conditions: the electromagnetic junction conditions, which were expressed in the traditional 3-dimensional form of classical electromagnetic theory;and the considerably more complicated gravitational junction conditions. It was shown that both—the electromagnetic and gravitational junction conditions—were satisfied. The mass, charge and angular momentum were determined from the metric. Exact analytical formulae for the dipole moment and gyromagnetic ratio were also derived. The conditions, under which the latter formulae gave Blackett’s empirical result for rotating stars, were investigated. 展开更多
关键词 GRAVITATION Exact Solutions einstein-Maxwell equations Rotation CHARGED Dust
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Generally Unitary Solution to a System of Matrix Equations over the Quaternion Field
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作者 周立泰 汪远征 《Chinese Quarterly Journal of Mathematics》 CSCD 2001年第2期91-93,共3页
Generally unitary solution to the system of martix equations over the quaternion field [X mA ns =B ns ,X nn C nt =D nt ] is considered. A necessary and sufficient condition for the existence o... Generally unitary solution to the system of martix equations over the quaternion field [X mA ns =B ns ,X nn C nt =D nt ] is considered. A necessary and sufficient condition for the existence of and the expression for the generally unitary solution of the system are derived. 展开更多
关键词 generally unitary matrix system of matrix equations the quaternion field
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Minor Self-conjugate and Skewpositive Semidefinite Solutions to a System of Matrix Equations over Skew Fields
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作者 姜学波 《Chinese Quarterly Journal of Mathematics》 CSCD 2001年第2期86-90,共5页
Minor self conjugate (msc) and skewpositive semidefinite (ssd) solutions to the system of matrix equations over skew fields [A mn X nn =A mn ,B sn X nn =O sn ] are considered. Necessary and su... Minor self conjugate (msc) and skewpositive semidefinite (ssd) solutions to the system of matrix equations over skew fields [A mn X nn =A mn ,B sn X nn =O sn ] are considered. Necessary and sufficient conditions for the existence of and the expressions for the msc solutions and the ssd solutions are obtained for the system. 展开更多
关键词 minor self conjugate matrix skewpositive semidefinite matrix system of matrix equations skew field the real quatrnion field
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Determination of the solvation film thickness of dispersed particles with the method of Einstein viscosity equation 被引量:8
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作者 Changsheng Peng Shaoxian Son Shouci Lu 《Journal of University of Science and Technology Beijing》 CSCD 2005年第4期370-375,共6页
The dispersion of a solid particle in a liquid may lead to the formation of solvation film on the particle surface, which can strongly increase the repulsive force between particles and thus strongly affect the stabil... The dispersion of a solid particle in a liquid may lead to the formation of solvation film on the particle surface, which can strongly increase the repulsive force between particles and thus strongly affect the stability of dispersions. The solvation film thickness, which varies with the variation of the property of suspension particles and solutions, is one of the most important parameters of the solvation film, and is also one of the most difficult parameters that can be measured accurately. In this paper, a method, based on the Einstein viscosity equation of dispersions, for determining the solvation film thickness of particles is developed. This method was tested on two kinds of silica spherical powders (namely M1 and M2) dispersed in ethyl alcohol, in water, and in a water-ethyl alcohol mixture (1:1 by volume) through measuring the relative viscosity of dispersions of the particles as a function of the volume fraction of the dry particles in the dispersion, and of the specific surface area and the density of the particles. The calculated solvation film thicknesses on M1 are 7.48, 18.65 and 23.74 nm in alcohol, water and the water-ethyl alcohol mixture, 12.41, 12.71 and 13.13 nm on M2 in alcohol, water and the water-ethyl alcohol mixture, respectively. 展开更多
关键词 solvation film VISCOSITY film thickness einstein viscosity equation
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Average vector field methods for the coupled Schrdinger KdV equations 被引量:3
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作者 张弘 宋松和 +1 位作者 陈绪栋 周炜恩 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第7期242-250,共9页
The energy preserving average vector field (AVF) method is applied to the coupled Schr6dinger-KdV equations. Two energy preserving schemes are constructed by using Fourier pseudospectral method in space direction di... The energy preserving average vector field (AVF) method is applied to the coupled Schr6dinger-KdV equations. Two energy preserving schemes are constructed by using Fourier pseudospectral method in space direction discretization. In order to accelerate our simulation, the split-step technique is used. The numerical experiments show that the non-splitting scheme and splitting scheme are both effective, and have excellent long time numerical behavior. The comparisons show that the splitting scheme is faster than the non-splitting scheme, but it is not as good as the non-splitting scheme in preserving the invariants. 展开更多
关键词 coupled Schrodinger-KdV equations average vector field method splitting method Fourier pseu-dospectral method
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Multi-quadric Equations Interpolation and Its Applications to the Establishment of Crustal Movement Speed Field 被引量:4
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作者 YAO Yibin LIU Jingnan SHI Chuang TAO Benzao 《Geo-Spatial Information Science》 2002年第2期1-5,共5页
In this paper,multi_quadric equations interpolation is used to establish a widely covered and valuable speed field model,with which the crustal movement image is obtained.
关键词 multi_quadric equations interpolation speed field model crustal movement pattern
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A-E equation of potential field transformations in the wavenumber domain and its application 被引量:7
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作者 Chai Yupu 《Applied Geophysics》 SCIE CSCD 2009年第3期205-216,299,共13页
A shift sampling theory established by author (1997a) is a generalization of Fourier transform computation theory. Based on this theory, I develop an Algorithm-Error (A-E) equation of potential field transformatio... A shift sampling theory established by author (1997a) is a generalization of Fourier transform computation theory. Based on this theory, I develop an Algorithm-Error (A-E) equation of potential field transformations in the wavenumber domain, which not only gives a more flexible algorithm of potential field transformations, but also reveals the law of error of potential field transformations in the wavenumber domain. The DFT0η η(0.5, 0.5) reduction-to-pole (RTP) technique derived from the A-E equation significantly improves the resolution and accuracy of RTP anomalies at low magnetic latitudes, including the magnetic equator. The law (origin, form mechanism, and essential properties) of the edge oscillation revealed by the A-E equation points out theoretically a way of improving the effect of existing padding methods in high-pass transformations in the wavenumber domain. 展开更多
关键词 Potential field transformation Fourier transform shift sampling theory A-E equation DFT0η η(0.5 0.5) algorithm
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Nonlinear Spinor Field Equations in Gravitational Theory: Spherical Symmetric Soliton-Like Solutions 被引量:2
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作者 V. Adanhounme A. Adomou +1 位作者 F. P. Codo M. N. Hounkonnou 《Journal of Modern Physics》 2012年第9期935-942,共8页
This paper deals with an extension of a previous work [Gravitation & Cosmology, Vol. 4, 1998, pp 107-113] to exact spherical symmetric solutions to the spinor field equations with nonlinear terms which are arbitra... This paper deals with an extension of a previous work [Gravitation & Cosmology, Vol. 4, 1998, pp 107-113] to exact spherical symmetric solutions to the spinor field equations with nonlinear terms which are arbitrary functions of S=ψψ, taking into account their own gravitational field. Equations with power and polynomial nonlinearities are studied in detail. It is shown that the initial set of the Einstein and spinor field equations with a power nonlinearity has regular solutions with spinor field localized energy and charge densities. The total energy and charge are finite. Besides, exact solutions, including soliton-like solutions, to the spinor field equations are also obtained in flat space-time. 展开更多
关键词 Lagrangian Static SPHERICAL SYMMETRIC Metric field equationS einstein equationS Dirac equation ENERGY-MOMENTUM Tensor Charge Density Current Vector SOLITON-LIKE Solution
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Pulsation Solution to the Equation of Earth's Gravitational Field (Main Outcome) 被引量:1
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作者 JIANG Zhi Gold Headquarters, P.O.Box 9902, Beijing 100102 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2000年第2期297-300,共4页
Using d'Alembert equation as the approximation of Einstein's equation, a solution is given in this paper to the time-dependent gravitational equation of the Earth in consideration of the Earth's features, ... Using d'Alembert equation as the approximation of Einstein's equation, a solution is given in this paper to the time-dependent gravitational equation of the Earth in consideration of the Earth's features, which describes the characteristics of pulsation of the Earth and the structures of spherical layers of its interior, thus providing a theoretical basis for establishing the idea of mantle pulsation. 展开更多
关键词 d'Alembert equation formula of gravitational field spherical layers density model mantle pulsation
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