In the classical vacuum Maxwell-Lorentz theory the self-force of a charged point particle is infinite. This makes classical mass renormalization necessary and, in the special relativistic domain, leads to the Abraham-Lorentz-Dirac equation of motion possessing unphysical run-away and pre-acceleration solutions. In this paper we investigate whether the higher-order modification of classical vacuum electrodynamics suggested by Bopp, Lande, Thomas and Podolsky in the 1940s, can provide a solution to this problem. Since the theory is linear, Green-function techniques enable one to write the field of a charged point particle on Minkowski spacetime as an integral over the particle's history. By introducing the notion of timelike worldlines that are "bounded away from the backward light-cone" we are able to prescribe criteria for the convergence of such integrals. We also exhibit a timelike worldline yielding singular fields on a lightlike hyperplane in spacetime. In this case the field is mildly singular at the event where the particle crosses the hyperplane. Even in the case when the Bopp-Podolsky field is bounded, it exhibits a directional discontinuity as one approaches the point particle. We describe a procedure for assigning a value to the field on the particle worldline which enables one to define a finite Lorentz self-force. This is explicitly derived leading to an integro-differential equation for the motion of the particle in an external electromagnetic field. We conclude that any worldline solutions to this equation belonging to the categories discussed in the paper have continuous 4-velocities.
We consider the self-interaction phenomenon in the framework of the Bopp-Podolsky electrodynamics. In the present paper, we obtain the self-interaction potential energy of a charge at rest for the spacetimes with topological defects of two types: for the axially symmetric spacetime of the straight cosmic string and the spherically symmetric global monopole spacetime. It is shown that the behavior of this expression depends essentially on the angular defect, in spite of the Bopp-Podolsky model parameter, which plays the role of a scale factor. In contrast with the usual Maxwell electrodynamics,…
A study of the radiation-reaction on a point charge that moves along a constant applied electric field in an electromagnetic Bopp-Landé-Thomas-Podolsky vacuum
Bopp-Podolsky electrodynamics is generalized to curved space-times. The equations of motion are written for the case of static spherically symmetric black holes and their exterior solutions are analyzed using Bekenstein's method. It is shown the solutions split-up into two parts, namely a non-homogeneous (asymptotically massless) regime and a homogeneous (asymptotically massive) sector which is null outside the event horizon. In addition, in the simplest approach to Bopp-Podolsky black holes, the non-homogeneous solutions are found to be Maxwell's solutions leading to a Reissner-Nordström blac…
Radiation-Reaction on the Straight-Line Motion of a Point Charge accelerated by a constant applied Electric Field in an Electromagnetic Bopp-Landé-Thomas-Podolsky vacuum
Lancaster University（兰卡斯特大学）；Rutgers, The State University of New Jersey（新泽西州立罗格斯大学）
We consider a vector-tensor gravitational model with terms quadratic in the Maxwell tensor derivatives, called the Bopp-Podolsky term. The gravitational field equations of the model and the equations describing the evolution of the vector field are obtained and their Newtonian limit is investigated. The cosmological implications of a Bopp-Podolsky type dark energy term are investigated for a Bianchi type I homogeneous and anisotropic geometry for two models, corresponding to the absence and presence of the self-interacting potential of the field, respectively. The time evolutions of the Hubble…
We consider the motion of charged point particles on Minkowski spacetime. The questions of whether the self-force is finite and whether mass renormalisation is necessary are discussed within three theories: In the standard Maxwell vacuum theory, in the non-linear Born-Infeld theory and in the higher-order Bopp-Podolsky theory. In a final section we comment on possible implications for the theory of the self-force in gravity.
In the Born, Infeld, Bopp, Podolsky and Dirac theories the electron mass is finite (or zero), but gravity effects have not been considered. Shirokov and Fisher showed that in studying of origin of elemental particle masses we can not neglect these effects. Gravity field plays an essential role in interpretation of particle mass. It has been shown that for point-like charge the general solution of gravity and electromagnetic (EM) equations that contains arbitrary function $μ(r)$, can in special case of this function, describe gravity and EM fields that do not have singularities in full range of…
Extended Theories of Electrodynamics in $f(R)$ Gravity
Scuola Superiore Meridionale（南方高等学院）；INFN Sez. di Napoli（意大利国家核物理研究所那不勒斯分部）；Dipartimento di Fisica “E. Pancini（环境与空间物理化学实验室（LPC2E）, 法国国家科学研究中心（CNRS）, 奥尔良大学）；Laboratoire de Physique et Chimie de l’Environnement et de l’Espace (LPC2E) UMR 7328 Centre National de la Recherche Scientifique (CNRS), Université d’Orléans (UO)（中部地区宇宙科学观测站（OSUC）, 法国国家科学研究中心（CNRS）, 巴黎天文台, 巴黎文理研究大学）；Observatoire des Sciences de l’Univers en region Centre (OSUC) UMS 3116 Université d’Orléans (UO), Centre National de la Recherche Scientifique (CNRS) Observatoire de Paris (OP), Université Paris Sciences & Lettres (PSL)
It is shown that a well-defined expression for the total electromagnetic force $f^{em}$ on a point charge source of the classical electromagnetic field can be extracted from the postulate of total momentum conservation whenever the classical electromagnetic field theory satisfies a handful of regularity conditions. Amongst these is the generic local integrability of the field momentum density over a neighborhood of the point charge. This disqualifies the textbook Maxwell-Lorentz field equations, while the Maxwell-Bopp-Lande-Thomas-Podolsky field equations qualify, and presumably so do the Maxw…
Einstein, Infeld, and Hoffmann (EIH) claimed that the field equations of general relativity theory alone imply the equations of motion of neutral matter particles, viewed as point singularities in space-like slices of spacetime; they also claimed that they had generalized their results to charged point singularities. While their analysis falls apart upon closer scrutiny, the key idea merits our attention. This rapport identifies necessary conditions for a well-defined general-relativistic joint initial value problem of $N$ classical point charges and their electromagnetic and gravitational fie…
We review a technique for solving a class of classical linear partial differential systems of relevance to physics in Minkowski spacetime. All the equations are amenable to analysis in terms of complex solutions in the kernel of the scalar Laplacian and a complexified Hertz potential. The complexification prescription ensures the existence of regular physical solutions with chirality and propagating, non-singular, pulse-like characteristics that are bounded in all three spatial dimensions. The technique is applied to the source-free Maxwell, Bopp-Landé-Podolsky and linearised Einstein field sy…
