Electromagnetic Field Configuration Research Articles

Energetic Proton Losses Reveal Io's Extended and Longitudinally Asymmetrical Atmosphere

AbstractAlong the I24, I27, and I31 flybys of Io (1999–2001), the Energetic Particle Detector (EPD) onboard the Galileo spacecraft observed localized regions of energetic protons losses (155–1,250 keV). Using back‐tracking particle simulations combined with a prescribed atmospheric distribution and a magnetohydrodynamics (MHD) model of the plasma/atmosphere interaction, we investigate the possible causes of these depletions. We focus on a limited region within two Io radii, which is dominated by Io's SO2 atmosphere. Our results show that charge exchange of protons with the SO2 atmosphere, absorption by the surface and the configuration of the electromagnetic field contribute to the observed proton depletion along the Galileo flybys. In the 155–240 keV energy range, charge exchange is either a major or the dominant loss process, depending on the flyby altitude. In the 540–1,250 keV range, as the charge exchange cross sections are small, the observed decrease of the proton flux is attributed to absorption by the surface and the perturbed electromagnetic fields, which divert the protons away from the detector. From a comparison between the modeled losses and the data we find indications of an extended atmosphere on the day/downstream side of Io, a lack of atmospheric collapse on the night/upstream side as well as a more global extended atmospheric component (>1 Io radius). Our results demonstrate that observations and modeling of proton depletion around the moon constitute an important tool to constrain the electromagnetic field configuration around Io and the radial and longitudinal atmospheric distribution, which is still poorly understood.

Asymptotic-preserving gyrokinetic implicit particle-orbit integrator for arbitrary electromagnetic fields

We extend the asymptotic preserving and energy conserving time integrator for charged-particle motion developed in Ricketson and Chacón (2020) [36] to include finite Larmor-radius (FLR) effects in the presence of electric-field length-scales comparable to the particle gyro-radius (the gyro-kinetic limit). We introduce two modifications to the earlier scheme. The first is the explicit gyro-averaging of the electric field at the half time-step, along with an analogous modification to the current deposition, which we show preserves total energy conservation in implicit PIC schemes. The number of gyrophase samples is chosen adaptively, ensuring proper averaging for large timesteps and the recovery of full-orbit dynamics in the small time-step limit. The second modification is an alternating large and small time-step strategy that ensures the particle trajectory samples gyrophases evenly. We show that this strategy relaxes the time-step restrictions on the scheme, allowing even larger speed-ups than previously achievable. We demonstrate the new method with several single-particle motion tests in a variety of electromagnetic field configurations featuring gyro-scale variation in the electric field. The results demonstrate the advertised ability to capture FLR effects accurately even when significantly stepping over the gyration time-scale.

Особенности численного решения уравнений Максвелла методом FDTD в однородной и неоднородной формулировках

In this paper we investigate the features of the numerical
 FDTD solution of Maxwell’s equations formulated as Cauchy
 problems for the corresponding homogeneous and inhomogeneous
 systems of equations. It is shown that for the case
 of time-limited field sources the Cauchy problem for an inhomogeneous
 system is equivalent to the corresponding Cauchy
 problem for a homogeneous system. The criterion for evaluating
 the correctness of the obtained solution is defined. The
 features of the numerical solution of homogeneous and nonhomogeneous
 Cauchy problems for different forms of initial
 configurations of electromagnetic fields and setting pulses
 are analyzed. Necessary and sufficient conditions of correctness
 of the obtained solutions are formulated.

A new radiation reaction approximation for particle dynamics in the strong field regime

Context. Following particle trajectories in the intense electromagnetic field of a neutron star is prohibited by the large ratio between the cyclotron frequency ωB and the stellar rotation frequency Ω. No fully kinetic simulations on a macroscopic scale and with realistic field strengths have been performed so far due to the huge computational cost implied by this enormous scale of separation. Aims. In this paper, we derive new expressions for the particle velocity subject to strong radiation reaction that are intended to be more accurate than the current state-of-the-art expression in the radiation reaction limit regime, the so-called Aristotelian regime. Methods. We shortened the timescale hierarchy by solving the particle equation of motion in the radiation reaction regime, where the Lorentz force is always and immediately balanced by the radiative drag, and including a friction not necessarily opposite to the velocity vector, as derived in the Landau-Lifshitz approximation. Results. Starting from the reduced Landau-Lifshitz equation (i.e., neglecting the field time derivatives), we found expressions for the velocity depending only on the local electromagnetic field configuration and on a new parameter related to the field strength that controls the strength of the radiative damping. As an example, we imposed a constant Lorentz factor γ during the particle motion. We found that for ultra-relativistic velocities satisfying γ ≳ 10, the difference between strong radiation reaction and the radiation reaction limit becomes negligible. Conclusions. The new velocity expressions produce results similar in accuracy to the radiation reaction limit approximation. We therefore do not expect this new method to improve the accuracy of neutron star magnetosphere simulations. The radiation reaction limit is a simple but accurate, robust, and efficient way to follow ultra-relativistic particles in a strong electromagnetic field.

Didactic study on classical dynamics of an electrically charged particle under influence of a constant and uniform magnetic field

The main task of this work is to study, by means of algebraic methods, the influence of a constant and uniform magnetic field on the classical dynamics of an electrically charged particle. In this text, we initially deal with the Lorentz equation in 4-dimensional Minkowski spacetime. Also, the Taylor series expansion of the relativistic factor and its behavior in Galileo's regime of relativity are presented. Finally, the equations of motion of a charged classical particle under the influence of the classical electromagnetic field configuration of the constant magnetic field type in time and uniformly distributed in 3-dimensional space are presented.

Zooming in on the horizon when in its Meissner state

When approaching extremality, rotating black holes tend to expel the magnetic field in which they are immersed. This phenomenon, being reminiscent of the Meissner-Ochsenfeld effect in superconductors, is known as the black hole Meissner effect, and here we study it in the backreacting regime and from the near horizon perspective. By resorting to methods recently developed in the literature, which allow to compute conserved charges in the near horizon region, regardless the details of the asymptotia at large distance, we investigate the properties of the black hole horizon when in its Meissner state. We show that, when in such state, the horizon exhibits two sets of supertranslation symmetries as well as a symmetry generated by the local conformal group. The supertranslations are generated by two infinite sets of currents, one of which comes from local dilations of the advanced null coordinate at the horizon, and the other from local gauge transformations that preserve the electromagnetic field configuration at the horizon. We show that the evaluation of the conserved charges associated to these symmetries correctly reproduce the physical charges of the magnetized black holes and their thermodynamics. This represents a concrete application of the techniques developed in [1–3] and it extends the results of [4] to arbitrary values of the black hole charges. In addition, we elaborate on the charges computation at the horizon: we show the equivalence between the horizon charges and the evaluation of the corresponding Komar integrals. Besides, we show the validity of the Gauss phenomenon by explicitly relating near horizon charges with fluxes and charges computed by other techniques. All this provides a method to derive the thermodynamics of magnetized horizons in a quite succinct way, including the case of horizons exhibiting the Meissner effect.

Anomalous magnetohydrodynamics with temperature-dependent electric conductivity and application to the global polarization

We have derived the solutions of the relativistic anomalous magnetohydrodynamics with longitudinal Bjorken boost invariance and transverse electromagnetic fields in the presence of temperature or energy density dependent electric conductivity. We consider the equations of states in a high temperature limit or in a high chiral chemical potential limit. We obtain both perturbative analytic solutions up to the order of \hbar and numerical solutions in our configurations of initial electromagnetic fields and Bjorken flow velocity. Our results show that the temperature or energy density dependent electric conductivity plays an important role to the decaying of the energy density and electromagnetic fields. We also implement our results to the splitting of global polarization for \Lambda and \bar{\Lambda} hyperons induced by the magnetic fields. Our results for the splitting of global polarization disagree with the experimental data in low energy collisions, which implies that the contribution from gradient of chemical potential may dominate in the low energy collisions.

On the Time Integral of Electromagnetic Field

The integral over time of an electric or magnetic field in infinite limits (Bessonov integral) is considered; it is shown that it is equal to zero for any configuration of the free electromagnetic field with zero total energy. The connection between zero Bessonov integral and the impossibility of emission or absorption of a photon by a free charged particle is investigated. Exact expressions for the radiation field as well as its Fourier transform are obtained for an electric charge with an abrupt change in the velocity; it is shown that the Bessonov integral of such a radiation field equals zero as follows from the general statement. In conclusion it is shown that a nonzero Bessonov integral of the radiation field produced by an electric charge moving with acceleration, which has been reported in a number of publications, appears because of the incorrect decomposition of the total field of the accelerated charge into the radiative and nonradiative components.

High-order corrections to the radiation-free dynamics of an electron in the strongly radiation-dominated regime

A system of reduced equations is proposed for electron motion in the strongly radiation-dominated regime for an arbitrary electromagnetic field configuration. The approach developed here is used to analyze various scenarios of electron dynamics in this regime: motion in rotating electric and magnetic fields and longitudinal acceleration in a plane wave and in a plasma wakefield. The results obtained show that this approach is able to describe features of electron dynamics that are essential in certain scenarios, but cannot be captured in the framework of the original radiation-free approximation [Samsonov et al., Phys. Rev. A 98, 053858 (2018) and A. Gonoskov and M. Marklund, Phys. Plasmas 25, 093109 (2018)]. The results are verified by numerical integration of the nonreduced equations of motion with account taken of radiation reaction in both semiclassical and fully quantum cases.

Метод генерирования гравитационных волн посредством системы стоячих электромагнитных волн

In this paper, we consider the method of generating gravitational waves by means of a system of standing electromagnetic waves at the difference frequency in electromagnetic resonators and their further registration based on various types of detectors. As a factor of amplification of the amplitude of gravitational waves induced by the proposed method, the inverse dependence of their amplitude on the square of the difference frequency is considered, which is a consequence of Einstein’s equations for the studied configuration of electromagnetic fields in the resonator. The characteristics of gravitational waves associated with the electromagnetic field inside the resonator and gravitational waves in empty space are compared. The possibility of conducting an experiment on the generation and detection of gravitational waves with controlled parameters of the source and detector (Hertz experiment) on the basis of the proposed method has been investigated. Various types of existing and promising detectors of low-frequency gravitational waves are considered and an estimate of the source characteristics necessary for the successful detection of gravitational waves generated by this method is obtained. The effectiveness of the proposed approach is compared with other methods of generating gravitational waves. The specificity of the considered method of generating gravitational waves is noted, associated with the possibility of obtaining in laboratory conditions low-frequency gravitational waves with a frequency close to the frequency of gravitational waves of astrophysical sources and the amplitude significantly exceeding the amplitude of high-frequency gravitational waves, which can be generated on the basis of previously proposed methods

Effect of external electromagnetic field configuration on metal structure of welded joints of structural steel

The Paton Welding Journal, 2022, №10. International Scientific-Technical and Production Journal «The Paton Welding Journal» «The Paton Welding Journal» has been published monthly since 2000 in English, ISSN 0957-798X. «The Paton Welding Journal» is a cover-to-cover English translation of the «Avtomaticheskaya Svarka» (Automatic Welding) journal. The «Avtomaticheskaya Svarka» journal has been published monthly since 1948 in Russian, ISSN 005-111X.

Effects of Lorentz symmetry breaking by a tensor field subject to Coulomb-type potential on relativistic quantum oscillator

In this paper, we solve the Klein–Gordon oscillator analytically under Lorentz-violating effects defined by a tensor field subject to a Coulomb-type scalar potential. We obtain the bound-state solutions of the quantum system by choosing various electromagnetic field configurations and discuss the effects on the energy profiles and the wave function of these oscillator fields.

Conserved charges for rational electromagnetic knots

We revisit a newfound construction of rational electromagnetic knots based on the conformal correspondence between Minkowski space and a finite S^3-cylinder. We present here a more direct approach for this conformal correspondence based on Carter–Penrose transformation that avoids a detour to de Sitter space. The Maxwell equations can be analytically solved on the cylinder in terms of S^3 harmonics Y_{j;m,n}, which can then be transformed into Minkowski coordinates using the conformal map. The resultant “knot basis” electromagnetic field configurations have non-trivial topology in that their field lines form closed knots. We consider finite, complex linear combinations of these knot-basis solutions for a fixed spin j and compute all the 15 conserved Noether charges associated with the conformal group. We find that the scalar charges either vanish or are proportional to the energy. For the non-vanishing vector charges, we find a nice geometric structure that facilitates computation of their spherical components as well. We present analytic results for all charges for up to j=1. We demonstrate possible applications of our findings through some known previous results.

Radiation reaction and limiting acceleration

We investigate the strong acceleration properties of the radiation reaction force and identify a new and promising limiting acceleration feature in the Eliezer-Ford-O'Connell model; in the strong field regime, for many field configurations, we find an upper limit to acceleration resulting in a bound to the rate of radiation emission. If this model applies, strongly accelerated particles are losing energy at a much slower pace than predicted by the usual radiation reaction benchmark, the Landau-Lifshitz equation, which certainly cannot be used in this regime. We explore examples involving various ``constant'' electromagnetic field configurations and study particle motion in a light plane wave as well as in a material medium.

Photonic Spin Lattices: Symmetry Constraints for Skyrmion and Meron Topologies.

Symmetry and topology govern many electronic, magnetic, and photonic phenomena in condensed matter physics and optics, resulting in counterintuitive skyrmion, meron, and other phenomena important for modern technologies. Here we demonstrate photonic spin lattices as a new topological construct governed by the spin-orbit coupling in an optical field. The symmetry of the electromagnetic field in the presence of the spin-orbit interaction may result in only two types of photonic spin lattices: either hexagonal spin-skyrmion or square spin-meron lattices. We show that these spin structures correspond to the lowest energy of the electromagnetic field configuration, therefore, energetically stable. We further show that in the absence of spin-orbit coupling these spin topologies are degenerated in dynamic field skyrmions, unifying the description of electromagnetic field topologies. The results provide a new understanding of electromagnetic field topology and its transformations as well as new opportunities for applications in quantum technologies, spin optics, and topological photonics.

Lorentzian worldline path integral approach to Schwinger effect

We demonstrate that the positive frequency modes for a complex scalar field in a constant electric field (Schwinger modes), in three different gauges, can be represented as exact Lorentzian worldline path integral amplitudes. Although the mathematical forms of the mode functions differ in each gauge, we show that a simple prescription for Lorentzian worldlines' boundary conditions dispenses the Schwinger modes in all three gauges (that we considered) in a unified manner. Following that, using our formalism, we derive the exact Bogoliubov coefficients and, hence, the particle number, \textit{without} appealing to the well-known connection formulas for parabolic cylinder functions. This result is especially relevant in view of the fact that in a general electromagnetic field configuration, one does not have the luxury of closed-form solutions. We argue that the real time worldline path integral approach may be a promising alternative in such non-trivial cases. We also demonstrate, using Picard-Lefschetz theory, how the so-called worldline instantons emerge naturally from relevant saddle points that are complex.

Bogoliubov-Fermi surface with inversion symmetry and electron-electron interactions: Relativistic analogies and lattice theory

We show that the general low-energy Bogoliubov-de Genness Hamiltonian in a multiband superconductor with broken time reversal and preserved inversion symmetry is a generator of real four-dimensional representation of $SO(4)$. In the particular representation such an effective Hamiltonian is a purely imaginary matrix, and it is proportional to the antisymmetric tensor of a fictitious electromagnetic field which one can define in the momentum space. The quantum time evolution of the low-energy quasiparticle state becomes this way closely related to the classical relativistic motion of a charged particle in the presence of the Lorentz force that would be derived from such an electromagnetic field configuration. The condition for the emergence of a Bogoliubov-Fermi surface can then be understood as orthogonality of the fictitious electric and magnetic fields, which would allow zero Lorentz force. The corresponding zero-energy eigenstates are identified as the physical timelike and the unphysical spacelike solutions of the Lorentz force equation. We study the looming instability of the inversion-symmetric Bogoliubov-Fermi surface in presence of electron-electron interaction by formulating a concrete interacting model on the Lieb lattice that features the requisite $SO(4)$ kinetic energy term together with nearest-neighbor two-body repulsion. The latter is shown to favor dynamical breaking of the inversion symmetry. The inversion symmetry in our lattice model indeed becomes spontaneously broken at zero temperature at infinitesimal repulsion, with the original Bogoliubov-Fermi surface deformed and reduced in size. General features of this symmetry breaking phenomenon are discussed and a comparison with other works in literature is presented.

The 4-Dimensional Dirac Equation in Relativistic Field Theory

An important milestone in quantum physics has been reachedby the publication of the Relativistic Quantum MechanicalDirac Equation in 1928. However, the Dirac equationrepresents a 1-Dimensional quantum mechanical equationwhich is unable to describe the 4-Dimensional PhysicalReality.In this article the 4-Dimensional Relativistic QuantumMechanical Dirac Equation expressed in the vectorprobability functions  and the complex conjugated vectorprobability function  *will be published. To realize this, theclassical boundaries of physics has to be changed. It isnecessary to go back in time 300 years ago. More than 200years ago before the Dirac Equation had been published.A Return to the Inception of Physics. The time of IsaacNewton who published in 1687 in the “PhilosophiaeNaturalis Principia Mathematica” a Universal FundamentalPrinciple in Physics which was in Harmony with Science andReligion. The Universal Path, the Leitmotiv, the UniversalConcept in Physics. Newton found the concept of “UniversalEquilibrium” which he formulated in his famous thirdequation Action = - Reaction. This article presents a New Kind of Physics based on this Universal Fundamental Concept in Physics which results in a New Approach in Quantum Physics and General Relativity.The physical concept of quantum mechanical probability waves has been created during the famous 1927 5th Solvay Conference. During that period there were several circumstances which came together and made it possible to create an unique idea of material waves being complex (partly real and partly imaginary) and describing the probability of the appearance of a physical object (elementary particle). The idea of complex probability waves was new in the beginning of the 20th century. Since then the New Concept has been protected carefully within the Copenhagen Interpretation. When Schrödinger published his famous material wave equation in 1926, he found spherical and elliptical solutions for the presence of the electron within the atom. The first idea of the material waves in Schrödinger’s wave equation was the concept of confined Electromagnetic Waves. But according to Maxwell this was impossible. According to Maxwell’s equations Electromagnetic Waves can only propagate along straight lines and it is impossible that Light (Electromagnetic Waves) could confine with the surface of a sphere or an ellipse. For that reason these material waves in Schrödinger’s wave equation could only be of a different origin than Electromagnetic Waves. Niels Bohr introduced the concept of “Probability Waves” as the origin of the material waves in Schrödinger’s wave equation. And defined the New Concept that the electron was still a particle but the physical presence of the electron in the Atom was equally divided by a spherical probability function.In the New Theory it will be demonstrated that because of a mistake in the Maxwell Equations, in 1927 Confined Electromagnetic waves could not be considered to be the material waves expressed in Schrödinger's wave equation. The New Theory presents a new equation describing electromagnetic field configurations which are also solutions of the Schrodinger's wave equation and the relativistic quantum mechanical Dirac Equation and carry mass, electric charge and magnetic spin at discrete values.

A Return to the Inception of Physics

A Return to the Beginning (Inception|) of Physics. The time of Isaac Newton who published in 1687 in the “Philosophiae Naturalis Principia Mathematica” a Universal Fundamental Principle in Physics which was in Harmony with Science and Religion. The Universal Path, the Leitmotiv, the Universal Concept in Physics. Newton found the concept of “Universal Equilibrium” which he formulated in his famous third equation Action = - Reaction. This article presents a New Kind of Physics based on this Universal Fundamental Concept in Physics which results in a New Approach in Quantum Physics and General Relativity. The physical concept of quantum mechanical probability waves has been created during the famous 1927 5th Solvay Conference. During that period there were several circumstances which came together and made it possible to create an unique idea of material waves being complex (partly real and partly imaginary) and describing the probability of the appearance of a physical object (elementary particle). The idea of complex probability waves was new in the beginning of the 20th century. Since then the New Concept has been protected carefully within the Copenhagen Interpretation. When Schrödinger published his famous material wave equation in 1926, he found spherical and elliptical solutions for the presence of the electron within the atom. The first idea of the material waves in Schrödinger’s wave equation was the concept of confined Electromagnetic Waves. But according to Maxwell this was impossible. According to Maxwell’s equations Electromagnetic Waves can only propagate along straight lines and it is impossible that Light (Electromagnetic Waves) could confine with the surface of a sphere or an ellipse. For that reason these material waves in Schrödinger’s wave equation could only be of a different origin than Electromagnetic Waves. Niels Bohr introduced the concept of “Probability Waves” as the origin of the material waves in Schrödinger’s wave equation. And defined the New Concept that the electron was still a particle but the physical presence of the electron in the Atom was equally divided by a spherical probability function. In the New Theory it will be demonstrated that because of a mistake in the Maxwell Equations, in 1927 Confined Electromagnetic waves could not be considered to be the material waves expressed in Schrödinger’s wave equation. The New Theory presents a new equation describing electromagnetic field configurations which are also solutions of the Schrodinger’s wave equation and the relativistic quantum mechanical Dirac Equation and carry mass, electric charge and magnetic spin at discrete values

4-Dimensional Relativistic Quantum Mechanical Equilibrium in Gravitational-Electromagnetic Confinements

An important milestone in quantum physics was reached by the publication of the Relativistic Quantum Mechanical Dirac Equation in 1928. However, the Dirac equation represents a 1-Dimensional quantum mechanical equation which is unable to describe the 4-Dimensional Physical Reality. In this article, the 4-Dimensional Relativistic Quantum Mechanical Dirac Equation expressed in the vector probability functions and the complex conjugated vector probability function will be discussed. To realize this, the classical boundaries of physics has to be changed. It is necessary to go back in time more than 200 years ago before the Dirac Equation had been published. Isaac Newton who published in 1687 in the “Philosophiae Naturalis Principia Mathematica” a Universal Fundamental Principle in Physics was in Harmony with Science and Religion. Newton found the concept of “Universal Equilibrium” which he mentioned in his famous third equation, Action = Reaction. This article presents a New Kind of Physics based on this Universal Fundamental Concept in Physics which results in a New Approach in Quantum Physics and General Relativity. The physical concept of quantum mechanical probability waves has been originated during the famous 5th Solvay Conference in 1927. During that period there were several circumstances that came together and made it possible to create a unique idea of material waves being complex (partly real and partly imaginary) and describing the probability of the appearance of a physical object (elementary particle). The idea of complex probability waves was new in the beginning of the 20th century. Since then the New Concept has been protected carefully within the Copenhagen Interpretation. When Schrödinger published his well-known material wave equation in 1926, he found spherical and elliptical solutions for the presence of the electron within the atom. The first idea of the material waves in Schrödinger's wave equation was the concept of confined Electromagnetic Waves. But according to Maxwell, this was impossible. According to Maxwell's equations, Electromagnetic Waves can only propagate along straight lines and it is impossible that Light (Electromagnetic Waves) could confine with the surface of a sphere or an ellipse. For that reason, these material waves in Schrödinger's wave equation could only be of a different origin than Electromagnetic Waves. Niels Bohr introduced the concept of “Probability Waves” as the origin of the material waves in Schrödinger’s wave equation. And defined the New Concept that the electron was still a particle but the physical presence of the electron in the Atom was equally divided by a spherical probability function. In the New Theory, it will be demonstrated that because of a mistake in the Maxwell Equations, in 1927 Confined Electromagnetic waves could not be considered to be the material waves expressed in Schrödinger's wave equation. The New Theory presents a new equation describing electromagnetic field configurations which are also solutions of the Schrodinger's wave equation and the relativistic quantum mechanical Dirac Equation and carry mass, electric charge, and magnetic spin at discrete values.