Search results for "Maxwell's equation"

Maxwell’s Equations

2012

The empirical basis of electrodynamics is defined by Faraday’s law of induction, by Gauss’ law, by the law of Biot and Savart and by the Lorentz force and the principle of universal conservation of electric charge. These laws can be tested – confirmed or falsified – in realistic experiments. The integral form of the laws deals with physical objects that are one-dimensional, two-dimensional, or three-dimensional, that is to say, objects such as linear wires, conducting loops, spatial charge distributions, etc. Thus, the integral form depends, to some extent, on the concrete experimental set-up. To unravel the relationships between seemingly different phenomena, one must switch from the integ…

On the theory of domain structure in ferromagnetic phase of diluted magnetic semiconductors

2006

Abstract We present a comprehensive analysis of domain structure formation in ferromagnetic phase of diluted magnetic semiconductors (DMS) of p-type. Our analysis is carried out on the base of effective magnetic free energy of DMS calculated by us earlier [Yu.G. Semenov, V.A. Stephanovich, Phys. Rev. B 67 (2003) 195203]. This free energy, substituting DMS (a disordered magnet) by effective ordered substance, permits to apply the standard phenomenological approach to domain structure calculation. Using coupled system of Maxwell equations with those obtained by minimization of above free energy functional, we show the existence of critical ratio ν cr of concentration of charge carriers and ma…

A numerical meshless particle method in solving the magnetoencephalography forward problem

2012

In this paper, a numerical meshless particle method is presented in order to solve the magnetoencephalography forward problem for analyzing the complex activation patterns in the human brain. The forward problem is devoted to compute the scalp potential and magnetic field distribution generated by a set of current sources representing the neural activity, and in this paper, it has been approached by means of the smoothed particle hydrodynamics method suitably handled. The Poisson equation generated by the quasi-stationary Maxwell's curl equations, by assuming Neumann boundary conditions has been considered, and the current sources have been simulated by current dipoles. The adopted meshless…

The zitterbewegung interpretation of quantum mechanics as theoretical framework for ultra-dense deuterium and low energy nuclear reactions

2017

This paper introduces a Zitterbewegung model of the electron by applying the principle of Occam's razor to the Maxwell's equations and by introducing a scalar component in the electromagnetic field. The aim is to explain, by using simple and intuitive concepts, the origin of the electric charge and the electromagnetic nature of mass and inertia. The Zitterbewegung model of the electron is also proposed as the best suited theoretical framework to study the structure of Ultra-Dense Deuterium (UDD), the origin of anomalous heat in metal-hydrogen systems and the possibility of existence of "super-chemical" aggregates at Compton scale.

Unified Field Theory and Occam's Razor: Simple Solutions to Deep Questions

2021

Unified Field Theory was an expression first used by Einstein in his attempt to unify general relativity with electromagnetism. Unified Field Theory and Occam's Razor attempts to provide real answers to foundational questions related to this unification and should be of high interest to innovative scientists. A diverse group of contributing authors approach an old problem with an open-mindedness that presents a new and fresh perspective. The following topics are discussed in detail in the hope of a fruitful dialogue with all who are interested in this subject: The composition of electrons, photons, and neutrinos. The relationship of quantum mechanics to general relativity. The four-componen…

Unconditionally stable meshless integration of Maxwell's eqautions

2013

Three-dimensional splitting dynamics of giant vortices in Bose-Einstein condensates

2018

We study the splitting dynamics of giant vortices in dilute Bose-Einstein condensates by numerically integrating the three-dimensional Gross-Pitaevskii equation in time. By taking advantage of tetrahedral tiling in the spatial discretization, we decrease the error and increase the reliability of the numerical method. An extensive survey of vortex splitting symmetries is presented for different aspect ratios of the harmonic trapping potential. The symmetries of the splitting patterns observed in the simulated dynamics are found to be in good agreement with predictions obtained by solving the dominant dynamical instabilities from the corresponding Bogoliubov equations. Furthermore, we observe…

Theoretical principles of near-field optical microscopies and spectroscopies

2000

International audience; This paper deals with the principles of detection of optical signals near a surface in a manner permitting the mapping of the distribution of the fields close to various kinds of illuminated samples. We begin with a discussion of the main physical properties of the optical fields near a surface in the absence of any probe tip. This mainly concerns phenomena involving evanescent waves for which the local decay lengths are governed not only by the sizes but also by the intrinsic properties of the surface structures. The interpretation of the detection process is reviewed on the basis of a discussion about the possibility of establishing direct comparisons between exper…

Semi-discrete Galerkin approximation method applied to initial boundary value problems for Maxwell's equations in anisotropic, inhomogeneous media

1981

SynopsisIn this paper the semi-discrete Galerkin approximation of initial boundary value problems for Maxwell's equations is analysed. For the electric field a hyperbolic system of equations is first derived. The standard Galerkin method is applied to this system and a priori error estimates are established for the approximation.

Efficient Time Integration of Maxwell's Equations with Generalized Finite Differences

2015

We consider the computationally efficient time integration of Maxwell’s equations using discrete exterior calculus (DEC) as the computational framework. With the theory of DEC, we associate the degrees of freedom of the electric and magnetic fields with primal and dual mesh structures, respectively. We concentrate on mesh constructions that imitate the geometry of the close packing in crystal lattices that is typical of elemental metals and intermetallic compounds. This class of computational grids has not been used previously in electromagnetics. For the simulation of wave propagation driven by time-harmonic source terms, we provide an optimized Hodge operator and a novel time discretizati…