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Related papers: The Helmholtz Theorem and Superluminal Signals

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Electric vector potential $\Theta(\boldsymbol{r})$ is a legitimate but rarely used tool to calculate the steady electric field in free-charge regions. Commonly, it is preferred to employ the scalar electric potential $\Phi(\boldsymbol{r})$…

Classical Physics · Physics 2021-03-10 Robert Salazar , Camilo Bayona-Roa , Gabriel Téllez

We find the electric field of a point charge in `truncated hyperbolic motion', in which the charge moves at a constant velocity followed by motion with a constant acceleration in its instantaneous rest frame. The same Lienard-Wiechert…

Classical Physics · Physics 2015-07-08 Jerrold Franklin

Time-harmonic electromagnetic waves in vacuum are described by the Helmholtz equation $\Delta u+\omega ^{2}u=0 $ for $ (x,y,z) \in \mathbb{R}^3 $. For the evolution of such waves along the $z$-axis a Schr\"odinger equation can be derived…

Analysis of PDEs · Mathematics 2021-04-02 Maximilian Klumpp , Guido Schneider

Compact hyperkaehler manifolds are higher-dimensional generalizations of K3 surfaces. The classical Global Torelli theorem for K3 surfaces, however, does not hold in higher dimensions. More precisely, a compact hyperkaehler manifold is in…

Algebraic Geometry · Mathematics 2013-09-12 Daniel Huybrechts

This paper is the first one of two serial articles, whose goal is to prove convergence of HX Preconditioner (proposed by Hiptmair and Xu 2007) for Maxwell's equations with jump coefficients. In this paper we establish various extensions of…

Numerical Analysis · Mathematics 2020-01-17 Qiya Hu

In this paper we present thoughtful comments on the paper `Bessel beams and signal propagation' showing that the main claims of that paper are wrong. Moreover, we take the opportunity to show the non trivial and indeed surprising result…

Classical Physics · Physics 2009-11-07 E. Capelas de Oliveira , W. A. Rodrigues , D. S. Thober , A. L. Xavier

Let $X$ be a Hamiltonian vector field defined on a symplectic manifold $(M,\omega)$, $g$ a nowhere vanishing smooth function defined on an open dense subset $M^0$ of $M$. We will say that the vector field $Y = gX$ is conformally…

Symplectic Geometry · Mathematics 2011-02-22 Charles-Michel Marle

The main result is the identification of the orthogonal complement of the subalgebra of conformal vector field inside the algebra of all vector fields of a compact flat 2-manifold. As a fundamental tool, the complete Hodge decomposition for…

Differential Geometry · Mathematics 2016-09-05 Stephen Marsland , Robert McLachlan , Klas Modin , Matthew Perlmutter

The problem of formulating a manifest covariant Hamiltonian theory of General Relativity in the presence of source fields is addressed, by extending the so-called "DeDonder-Weyl" formalism to the treatment of classical fields in curved…

General Relativity and Quantum Cosmology · Physics 2016-09-16 Claudio Cremaschini , Massimo Tessarotto

For any given spacetime the choice of time coordinate is undetermined. A particular choice is the absolute time associated with a preferred vector field. Using the absolute time Hamilton's equations are $- (\delta H_{c})/(\delta…

General Relativity and Quantum Cosmology · Physics 2011-04-04 Mark D. Roberts

In a calculation that directly parallels the derivation of the Thomas precession, the first time derivative of the retarded potentials is derived. The solutions have to be integrated in time to obtain the potential solution. The Thomas…

General Relativity and Quantum Cosmology · Physics 2014-09-19 Gary Osborn

This paper introduces a time-domain combined field integral equation for electromagnetic scattering by a perfect electric conductor. The new equation is obtained by leveraging the quasi-Helmholtz projectors, which separate both the unknown…

Numerical Analysis · Mathematics 2024-07-22 Van Chien Le , Pierrick Cordel , Francesco P. Andriulli , Kristof Cools

The Boltzmann H-theorem implies that the solution to the Boltzmann equation tends to an equilibrium, that is, a Maxwellian when time tends to infinity. This has been proved in varies settings when the initial energy is finite. However, when…

Analysis of PDEs · Mathematics 2017-04-03 Yoshinori Morimoto , Tong Yang , Huijiang Zhao

Advanced potential solution of Maxwell equations isn't often accepted. We have proven if without advanced potential, it is not possible to satisfy the Maxwell equations. We also shown that it is not the Poynting vector related energy…

Classical Physics · Physics 2017-04-12 Shuang-ren Zhao , Kevin Yang , Kang Yang , Xingang Yang , Xintie Yang

A little error was eliminated from Hertz equations. New Hertz equations do not contradict to all electromagnetic experiments. Therefore Hertz electrodynamics is the alternative to Einstein electrodynamics. It means that the question about…

General Physics · Physics 2007-05-23 A. Pechenkov

Vectorial analysis relating to derivation of deflection of light is presented. Curvilinear acceleration is distinguished from the Newtonian polar conic acceleration. The difference between the two is due to the curvature term. Lorentz…

General Physics · Physics 2014-12-09 Vikram H. Zaveri

In this paper, we prove the linear and nonlinear ill-posedness of the well-known Kelvin-Helmholtz problem of the incompressible ideal magnetohydrodynamics (MHD) equations with transverse magnetic field. Our proof rigorously verifies that…

Analysis of PDEs · Mathematics 2025-05-07 Binqiang Xie , Boling Guo , Bin Zhao

In this paper, it is shown why Lorentz Transformation implies the general case where observed events are not necessarily in the inertia frame of any observer but assumes a special scenario when determining the length contraction and time…

General Physics · Physics 2012-09-24 Ibrahim M. Alabdulmohsin

Fermat's principle applied to a flat metric in the plane yields the phase of a Bessel function in the periodic domain for a constant index of refraction. Gravitational forces cause the index of refraction to vary and lead to a modified…

Mathematical Physics · Physics 2016-11-15 B. H. Lavenda

We derive the eikonal equation of light wavefront in the presence of Lorentz invariance violation (LIV) from the photon sector of the standard model extension (SME). The results obtained from the equations of $\mathbf{E}$ and $\mathbf{B}$…

High Energy Physics - Theory · Physics 2011-07-15 Zhi Xiao , Lijing Shao , Bo-Qiang Ma