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Related papers: Further Results on Null and Force-free Electromagn…

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We show that a large class of null electromagnetic fields are immune to any modifications of Maxwell's equations in the form of arbitrary powers and derivatives of the field strength. These are thus exact solutions to virtually any…

High Energy Physics - Theory · Physics 2018-03-09 Marcello Ortaggio , Vojtěch Pravda

Density functional theory (DFT) is an indispensable ab initio method in both quantum chemistry and condensed matter physics. Based on recent advancements in reduced density matrix functional theory (RDMFT), a variant of DFT that is believed…

Quantum Physics · Physics 2026-04-02 Chih-Chun Wang

When an unmagnetized plasma comes in contact with a material surface, the difference in mobility between the electrons and the ions creates a nonneutral layer known as the Debye sheath (DS). However, in magnetic fusion devices, the open…

Plasma Physics · Physics 2016-01-19 David Coulette , Giovanni Manfredi

The Null Surface Formulation of General Relativity is developed for 2+1 dimensional gravity. The geometrical meaning of the metricity condition is analyzed and two approaches to the derivation of the field equations are presented. One…

General Relativity and Quantum Cosmology · Physics 2015-06-25 Diego M. Forni , Mirta Iriondo , Carlos N. Kozameh

We prove that the associativity equations of two-dimensional topological quantum field theories are very natural reductions of the fundamental nonlinear equations of the theory of submanifolds in pseudo-Euclidean spaces and give a natural…

Differential Geometry · Mathematics 2008-11-26 O. I. Mokhov

We perform a three-dimensional (3D) global simulation of Earth's magnetosphere with kinetic reconnection physics to study the flux transfer events (FTEs) and dayside magnetic reconnection with the recently developed magnetohydrodynamics…

We construct the Effective Field Theory (EFT) of the teleparallel equivalent of general relativity (TEGR). Firstly, we present the necessary field redefinitions of the scalar field and the tetrads. Then we provide all the terms at…

General Relativity and Quantum Cosmology · Physics 2023-05-12 Maria Mylova , Jackson Levi Said , Emmanuel N. Saridakis

We present in this paper a rigorous theoretical framework to show stability, convergence and accuracy of improved edge-based and face-based smoothed finite element methods (bESFEM and bFS-FEM) for nearly-incompressible elasticity problems.…

Numerical Analysis · Mathematics 2016-11-26 Thanh Hai Ong , Claire E. Heaney , Chang-Kye Lee , G. R. Liu , H. Nguyen-Xuan

We introduce an ansatz for force-free electrodynamics in Minkowski spacetime under which the nonlinear system reduces to a semilinear scalar wave equation depending on two spacetime variables. This reduction yields explicit time-dependent…

General Relativity and Quantum Cosmology · Physics 2026-04-20 Yafet E. Sanchez Sanchez

Here we present a systematic study of force-free field equation for simple axisymmetric configurations in spherical geometry. The condition of separability of solutions in radial and angular variables leads to two classes of solutions:…

Solar and Stellar Astrophysics · Physics 2014-04-03 A. Prasad , A. Mangalam

We briefly present our version of noncommutative analysis over matrix algebras, the algebra of biquaternions ($\mathbb B$) in particular. We demonstrate that any $\mathbb B$-differentiable function gives rise to a null shear-free congruence…

Mathematical Physics · Physics 2023-11-27 Vladimir V. Kassandrov , Joseph A. Rizcallah , Ivan A. Matveev

Magnetars exhibit a variety of transient high-energy phenomena in the form of bursts, outbursts, and giant flares. It is a common belief that these events originate in the sudden release of magnetic energy due to the rearrangement of a…

High Energy Astrophysical Phenomena · Physics 2023-03-22 Petros Stefanou , Jose A. Pons , Pablo Cerdá-Durán

The Quantum Focusing Conjecture (QFC) lies at the foundation of holography and semiclassical gravity. The QFC implies the Bousso bound and the Quantum Null Energy Condition (QNEC). The QFC also ensures the consistency of the quantum…

High Energy Physics - Theory · Physics 2025-08-19 Raphael Bousso , Elisa Tabor

We describe a new scheme for evolving the equations of force-free electrodynamics, the vanishing-inertia limit of magnetohydrodynamics. This pseudospectral code uses global orthogonal basis function expansions to take accurate spatial…

High Energy Astrophysical Phenomena · Physics 2015-06-03 Kyle Parfrey , Andrei M. Beloborodov , Lam Hui

Let $(M,g^{TM})$ be a noncompact complete Riemannian manifold of dimension $n$, and let $F\subseteq TM$ be an integrable subbundle of $TM$. Let $g^F=g^{TM}|_{F}$ be the restricted metric on $F$ and let $k^F$ be the associated leafwise…

Differential Geometry · Mathematics 2022-08-30 Guangxiang Su , Xiangsheng Wang , Weiping Zhang

The combination of Finite Element Method (FEM) simulation and experimental photo-elasticity provides both qualitative and quantitative information about the stress field in a polymer composite and particularly along the fibre-matrix…

Materials Science · Physics 2007-05-23 H. Matthias Deuschle , Falk K. Wittel , Henry Gerhard , Gerhard Busse , Bernd-H. Kroeplin

The very existence of the physical vacuum provides a framework to propose a general mechanism for propelling bodies through an agency of electromagnetic fields, that seat in that medium. When two sub-systems of a general closed device…

Space Physics · Physics 2015-02-24 Mario J. Pinheiro

Thin beams made of magnetorheological elastomers embedded with hard magnetic particles (hard-MREs) are capable of large deflections under an applied magnetic field. We propose a comprehensive framework, comprising a beam model and 3D finite…

Soft Condensed Matter · Physics 2021-07-01 Dong Yan , Arefeh Abbasi , Pedro M. Reis

This thesis is concerned with equidistant foliations of Euclidean space, i.e. partitions into complete, connected, properly embedded smooth submanifolds. The space of leaves is an Alexandrov space of nonnegative curvature and the canonical…

Differential Geometry · Mathematics 2007-12-04 Christian Boltner

Free electromagnetic fields, satisfying Maxwell's equations with no charges and electric currents, can be described by complex vector fields. In the standard formulation with fields sharply dependent on position and time, one obtains…

Classical Physics · Physics 2023-06-16 Jerzy A. Przeszowski