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YES! We introduce a variable power Maxwell nonlinear electrodynamics theory which can remove the singularity of electric field of point-like charges at their locations. One of the main problems of Maxwells electromagnetic field theory is related to the existence of singularity for electric field of point-like charges at their locations. In other words, the electric field of a point-like charge diverges at the charge location which leads to an infinite self-energy. In order to remove this singularity a few nonlinear electrodynamics (NED) theories have been introduced. Born-Infeld (BI) NED theory is one of the most famous of them. However the power Maxwell (PM) NED cannot remove this singularity. In this paper, we show that the PM NED theory can remove this singularity, when the power of PM NED is less than $s<frac{1}{2}$.
In this work, the hydrogens ionization energy was used to constrain the free parameter $b$ of three Born-Infeld-like electrodynamics namely Born-Infeld itself, Logarithmic electrodynamics and Exponential electrodynamics. An analytical methodology capable of calculating the hydrogen ground state energy level correction for a generic nonlinear electrodynamics was developed. Using the experimental uncertainty in the ground state energy of the hydrogen atom, the bound $b>5.37times10^{20}Kfrac{V}{m}$, where $K=2$, $4sqrt{2}/3$ and $sqrt{pi}$ for the Born-Infeld, Logarithmic and Exponential electrodynamics respectively, was established. In the particular case of Born-Infeld electrodynamics, the constraint found for $b$ was compared with other constraints present in the literature.
Maxwells electrodynamics postulates the finite propagation speed of electromagnetic (EM) action and the notion of EM fields, but it only satisfies the requirement of the covariance in Minkowski metric (Lorentz invariance). Darwins force law of moving charges, which originates from Maxwells field theory complies the Lorentz invariance as well. Poincares principle stating that physical laws can be formulated with identical meaning on different geometries suggest, that the retarded EM interaction of moving charges might be covariant even in Euclidean geometry (Galilean invariance). Keeping the propagation speed finite, but breaking with Maxwells field theory in this study an attempt is made to find a Galilean invariant force law. Through the altering of the Lienard-Wiechert potential (LWP) a new retarded potential of two moving charges, the Common Retarded Electric Potential (CREP) is introduced which depends on the velocities of both interacting charges. The sought after force law is determined by means of the second order approximation of CREP. The law obtained is the Galilean invariant Webers force law, surprisingly. Its rediscovery from the second order approximation of a retarded electric potential confirms the significance of Webers force law and proves it to be a retarded and approximative law. The fact that Webers force law implies even the magnetic forces tells us that magnetic phenomena are a manifestation of the retarded electric interaction exclusively. The third order approximation of the CREP opens the possibility of EM waves, and the creation of a complete, Euclidean electrodynamics.
We present the derivation of conserved tensors associated to higher-order symmetries in the higher derivative Maxwell Abelian gauge field theories. In our model, the wave operator of the higher derived theory is a $n$-th order polynomial expressed in terms of the usual Maxwell operator. Any symmetry of the primary wave operator gives rise to a collection of independent higher-order symmetries of the field equations which thus leads to a series of independent conserved quantities of derived system. In particular, by the extension of Noethers theorem, the spacetime translation invariance of the Maxwell primary operator results in the series of conserved second-rank tensors which includes the standard canonical energy-momentum tensors. Although this canonical energy is unbounded from below, by introducing a set of parameters, the other conserved tensors in the series can be bounded which ensure the stability of the higher derivative dynamics. In addition, with the aid of auxiliary fields, we successfully obtain the relations between the roots decomposition of characteristic polynomial of the wave operator and the conserved energy-momentum tensors within the context of another equivalent lower-order representation. Under the certain conditions, the 00-component of the linear combination of these conserved quantities is bounded and by this reason, the original derived theory is considered stable. Finally, as an instructive example, we discuss the third-order derived system and analyze extensively the stabilities in different cases of roots decomposition.
It is demonstrated in this paper that the propagation of the electric wave field in a heterogeneous medium in 3D can sometimes be governed well by a single PDE, which is derived from the Maxwells equations. The corresponding component of the electric field dominates two other components. This justifies some past results of the second author with coauthors about numerical solutions of coefficient inverse problems with experimental electromagnetic data. In addition, since it is simpler to work in applications with a single PDE rather than with the complete Maxwells system, then the result of this paper might be useful to researchers working on applied issues of the propagation of electromagnetic waves in inhomogeneous media.
In this work we focus on the Carroll-Field-Jackiw (CFJ) modified electrodynamics in combination with a CPT-even Lorentz-violating contribution. We add a photon mass term to the Lagrange density and study the question whether this contribution can render the theory unitary. The analysis is based on the pole structure of the modified photon propagator as well as the validity of the optical theorem. We find, indeed, that the massive CFJ-type modification is unitary at tree-level. This result provides a further example for how a photon mass can mitigate malign behaviors.