广义相对论中双荷场源的电磁场张量

提出了一种求解双荷场源电磁场张量的方法.作为实例,讨论了含磁荷情况下Kerr-Newman时空中的电磁场张量,所得结果与直接进行复延拓ee+iq所得相同. 关键词：     

Calculation of electric and magnetic induced fields in humans subjected to electric power lines

In this work, analysis of the human body exposed to high voltage electric and magnetic fields is presented. The distribution of the electric field is obtained by using Laplace's equation. This relates the surface charge induced on the body to the potential in a reciprocal Laplace problem, which is then calculated by charge simulation method coupled with genetic algorithms to determine the appropriate arrangement of simulating charges inside the human body. The magnetic field intensity along the vertical center line of the human is calculated. Exposure to external electric and magnetic fields at power frequency induces electric field, magnetic field and currents inside the human body. The presented model for simulating electric and magnetic fields are a three dimensional field problem and introduced different types of charges to simulate the different elementary geometrical shapes of human body. The particular strength of the charge simulation method in this application is its ability to allow a detailed representation of the shape and posture of the human body. The results have been assessed through comparison induced current, electric field, magnetic field and there distribution over the body surface, as estimated in other experimental and computational work.     

A moiré method of visualizing electromagnetic force lines

We propose a simple moiré method of visualizing electromagnetic force lines. The indicial equation is first derived for the tangent (or normal) curve to the electric field (or magnetic induction) around two parallel-line charges (or currents). The derived equation is then shown to have a one-to-one correspondence with that of the moiré fringe formed by two overlapped radial gratings. Since the tangent (or normal) curve to the electric field (or the magnetic induction) corresponds to the direction of the electric (or magnetic) force on a test charge (or current), the radial grating moirés can be used for the visualization of electric (or magnetic) force lines.     

Tunneling Radiation of Charged and Magnetized Particles from the Reissner-Nordstr?m-de Sitter Black Holes with Magnetic Charges

We extended the Parikh-Wilczek’s method to calculate the tunneling radiation of charged and magnetized particles from the event horizon and the cosmological horizon of the Reissner-Nordstr?m-de Sitter black hole with magnetic charges. We reconstructed the electromagnetic field tensor and recalculated the Lagrangian of the field corresponding to the source with electric and magnetic charges. By viewing the eclectic and magnetic charges as an equivalent electric charge, we obtained the tunneling rate of the charged and magnetized particles. Our calculation supports the conclusion given by Parikh and Wilczek that the emission spectrum is no longer purely thermal, and the emission process supports the information conservation.     

Interference phase of mass neutrino in CM space--time

In the gravitational field of central mass with electric and magnetic charges and magnetic moment (CM space-time), this paper calculates the interference phase of mass neutrino along geodesic in the radial direction, and discusses the contribution of the electric and magnetic charges and magnetic moment of the central mass to the phase.     

A comment on generalized electromagnetism and dirac algebra

We show that, contrary to a recent claim by G. Fryberger, it is not possible within the Clifford bundle formalism to write a local Lagrangian which gives simultaneously the field equations and the equations of motion of electric charges and (non-topological), magnetic monopoles, and the generalized field equations.     

Tunneling of Charged and Magnetized Fermions from the Reissner-Nordström Black Hole with Magnetic Charges

The Kerner-Mann fermions tunneling framework is extended to the spin particles with electric and magnetic charges in this paper. We rewrite the electromagnetic field tensor and the Lagrangian of the field corresponding to the source with electric and magnetic charges to redefine an equivalent charge. We only consider the case that the ratio of the electric charge and magnetic charge of the emission is constant and equal to the source. The result shows that when the energy conservation together with the electric charge and magnetic charge conservations are taken into account in the dynamical background space time, the emission rate agrees with the underlying unitary theory and the actual radiation spectrum of charged and magnetized fermions also derivates from the pure thermal one.     

Charge definition in non-abelian gauge theories

Conserved gauge-invariant electric and magnetic charges are defined for non-abelian gauge theories in terms of the asymptotic symmetries of the field configurations. They are expressed as flux integrals. Illustrations include the magnetic charge of the 't Hooft-Polyakov monopole and the electric and magnetic charges of the Julia-Zee dyon.     

Hawking radiation of dyon particles from the Einstein –Maxwell-Dilaton–Axion black hole via covariant anomaly

Hawking radiation of particles with electric and magnetic charges from the Einstein–Maxwell-Dilaton–Axion black hole is derived via the anomaly cancellation method, initiated by Robinson and Wilczek and elaborated by Banerjee and Kulkarni recently. We reconstruct the electromagnetic field tensor to redefine the gauge potential and equivalent charge corresponding to the source with electric and magnetic charges. We only adopt the covariant gauge and gravitational anomalies to discuss the near-horizon quantum anomaly in the dragging coordinate frame. Our result shows that Hawking radiation in this case also can be reproduced from the viewpoint of anomaly.     

Renormalization of the QEMD of a dyon field

A renormalized quantum electromagnetodynamics (QEMD) of a dyon field is defined. Finite and n-independent answers can be obtained in each order of the loop expansion for all processes. The electric and magnetic charges are not constrained with the Dirac condition and therefore perturbation theory can be made reliable. The renormalized theory is found to possess exact dual invariance. Comparisons with the general QEMD of electric and magnetic charges are made.     

Induction of superconductivity by strong electric field

It is shown that strong electric field perpendicular to the surface of a solid with free charges creates the surface inhomogeneous superconducting state with critical parameters depending on the surface electrical potential only.The critical temperature and magnetic field of the surface inhomogeneous state can be high in the strong electric field.     

Magnetic monopole-like response in metamaterials

In this paper, we explored magnetic monopole-like responses in metamaterials. We designed a sub-wavelength metamolecule that is composed of two dielectric-spaced split-ring resonators. In response to incident waves, the induced magnetic field in the metamolecule resembles that of a two-dimensional magnetic monopole. The magnetic monopole-like response is resulted from electric resonance of the metamolecule, so an electric dipole is always attached. By combining two mirror-symmetric metamolecules with inward and outward radial magnetic fields, magnetic dipole-like responses can be produced just as an electric dipole is formed by separating two opposite-signed electric charges.     

Standstill Electric Charge Generates Magnetostatic Field under Born-Infeld Electrodynamics

The Abelian Born-Infeld classical non-linear Electrodynamic has been used to investigate the electric and magnetostatic fields generated by a point-like electric charge at rest in an inertial frame. The results show a rich internal structure for the charge. Analytical solutions have also been found. Such fields configurations have been interpreted in terms of vacuum polarization and magnetic-like charges produced by the very high strengths of the electric field considered. Apparently non-linearity is responsible for the emergence of an anomalous magnetostatic field suggesting a possible connection to that created by a magnetic dipole composed of two magnetic charges with opposite signs. Consistently in situations where the Born-Infeld field strength parameter is free to become infinite, Maxwell’s regime takes over, the magnetic sector vanishes and the electric field assumes a Coulomb behavior with no trace of a magnetic component. The connection to other monopole solutions, like Dirac’s and ’tHooft’s Poliakov’s types are also discussed. Finally, some speculative remarks are presented in an attempt to explain such fields.     

A microscopic semiclassical confining field equation forU(1) lattice gauge theory in 2+1 dimensions

We present a semiclassical nonlinear field equation for the confining field in 2+1-dimensionalU(1) lattice gauge theory (compact QED). The equation is derived directly from the underlying microscopic quantum Hamiltonian by means of truncation. Its nonlinearities express the dynamic creation of magnetic monopole currents leading to the confinement of the electric field between two static electric charges. We solve the equation numerically and show that it can be interpreted as a London relation in a dual superconductor.     

Chaos in the hydrogen atom interacting with external fields

In this review we discuss the chaotic dynamics (both classical and quantal aspects) of a simple atomic system, namely hydrogen atom interacting with time independent and time dependent external fields. These include: i) static electric field, ii) static magnetic field, iii) combined electric and magnetic fields, in parallel and perpendicular configuration, iv) instantaneous and generalized van der Waals field, v) mass anisotropy and vi) linearly and circularly polarized microwave fields.     

有关运动超导体电磁性质的几点讨论

在伦敦方程和电磁场的洛伦兹变换的基础上讨论了在磁场中运动的第一类超导平板的电磁性质。结果表明临界磁场将随超导体的速度的增加而减小 ;在穿透层内有一指数衰减的屏蔽电荷分布 ,其符号与超导体表面由运动感生的电荷相反、数量相等。屏蔽电荷屏蔽了表面电荷产生的感应电场 ,使电场和磁场一样在穿透层内指数衰减 ,在远离表面的内部 ,感应电场被完全屏蔽     

A one-potential formulation of the quantum field theory of magnetic poles

We formulate a new approach to the quantum field theory of electric and magnetic charges. Its advantages relative to existing formulations are that (a) it is a one-potential lagrangian one, (b) it has a canonical structure and (c) it representys a natural generalization of Dirac's quantum mechanical theory to field theory. Our formulation is non-local in coordinate space, but yields Feynman rules that are local in momentum space.     

Oscillator strengths of optical transitions of a cylindrical shell: Crossed static electric and magnetic fields

The single-electron eigenstates of a cylindrical shell are determined as functions of the applied crossed electric and magnetic fields in the effective-mass approximation. The system considered consists of donor charges taken to be uniformly distributed within an inner core of infinitely long length. The core is concentrically enveloped by a semiconducting material of finite thickness; which is essentially the host material. This configuration of the donor charges sets up a spatially varying electric field nonetheless with only the radial component. In addition, a uniform magnetic field is applied parallel to the axis of symmetry of the inner core. As is well known, the axial applied magnetic field lifts the double degeneracies of the electron’s subbands characterized by the same azimuthal quantum numbers which differ only in sign. The main effect of increasing the external electric field is to elevate the various energy subbands, more or less to the same extent, to higher values. Further, evaluations of the oscillator strengths of optical transitions of the cylindrical shell are carried out within the dipole approximation. The radiation field is taken to be that of circularly polarized light incident along the axis of the core. The oscillator strengths of optical transitions are found to increase with an increase of the applied magnetic field, particularly in the regime of small magnetic fields. In contrast, the oscillator strengths of these optical interactions become suppressed as the donor charge density is increased.     

A model of electric field-driven charge disordering

We propose a model for an electric field-induced transition from an ordered phase of the lattice–gas system with alternating charges to a disordered phase. We assume the hopping conductivity of charge carriers. The analysis of this model using Monte Carlo method demonstrates that sufficiently high electric field can disorder ordered phases inducing flow of charges in a system with blocked conduction pathways.     

Two identical conducting spheres with same potential in a uniform electric field

Interaction, polarization, and charges or electric field distribution of conducting spheres in applied electric field are in many fields including electrorheological fluids, electrophoresis, and electrical engineering. A system with two equipotential conducting spheres in an applied uniform electric field is analyzed by image method. A new method is put forward to calculate the image charges distribution when using image method, which ensures the validity of image method to analyze equipotential cases. An apparatus is constructed to measure the force experimentally as well. Results show that the distribution of electric field and electric interaction are different with the case not equipotential.