Talk:Liénard–Wiechert potential

Figures of Liénard-Wiechert potentials[edit]

Although Liénard-Wiechert potentials are very well defined, there are no figures in literature showing them. But figures would be very helpfull for a deeper understanding of this kind of potentials.

Therefore I adapted an algorithm presented in ^[1] to draw a figure of the Liénard-Wiechert potential of a fast electron. The Matlab program is presented in the description of the figure and can be checked by anybody.

Xxanthippe deleted this very important figure.

Liénard-Wiechert-potential of a fast electron moving with 91 percent of the speed of light in x-direction.

References

^ A. Malcherek: Elektromagnetismus und Gravitation, Die Vereinheitlichung der klassischen Physik, Springer-Vieweg, 2022, https://doi.org/10.1007/978-3-658-35956-0

Equations have to be revised?[edit]

Danger, the article at present is nutter jumble at the start. Please consult the original paper by Feynman and Wheeler for a pretty damn lucid introduction. ;) 168.105.107.215 (talk) 07:02, 20 November 2014 (UTC)[reply]

This was constructed largely from class notes, with some reference to Griffith's Intro to Electrodynamics 3rd Ed. (10.3.2 "Fields of a Moving Point Charge"). Nimur 21:24, 11 March 2007 (UTC)[reply]

There is a throwaway line in the lede: " The Liénard–Wiechert potentials can be generalized according to gauge theory." We need an explanation or expansion of this. Xxanthippe (talk) 04:35, 31 October 2013 (UTC).[reply]

I have removed an obscurity. Is there an expression available for these potentials in the Coulomb gauge? Xxanthippe (talk) 00:11, 1 November 2013 (UTC).[reply]

that question is meaningless since they arise from the lorenz gauge. The coulomb gauge is the worst for that question, all potentials are instantaneous in coulomb gauge so they don't "propagate". omg Klinfran (talk) 00:18, 3 May 2018 (UTC)[reply]

It has been shown in 2008 [2] that the formulas found have to be reviewed (revision is not mentioned in this page) to be totally correct in the case of accelerated charges.

So does this mean the equations are incorrect, or not? If incorrect, why do they have a Wikipedia article? Weasel a bit?

I would prefer a text to reference [2]. But it is not possible to tell if [2] has been applied here, or if the threat merely looms. Has anyone checked [2] for correctness? 89.217.19.149 (talk) 17:24, 4 November 2014 (UTC)[reply]

Why is the equation for retarded time defined recusively? I think that is a typo. — Preceding unsigned comment added by 67.136.58.98 (talk) 23:00, 9 January 2015 (UTC)[reply]

Error[edit]

The vector potential A is a function of time AND position. Therefore the electric field uses the PARTIAL derivative of A with respect to t, not the "straight" one. Big mistake.Klinfran (talk) 09:26, 9 January 2018 (UTC)[reply]

Covariance[edit]

The link may be ambiguous. "Covariance" in math statistics is not a synonym for "covariant" in field theory.

(Please excuse me for reverting and not adding the reason: there was a misclick)

Implications[edit]

There are some statements in this section that require sources and clarification as to whether the particular statement is consensus in the field. For instance, the following statements are definitely not consensus: "Advanced fields are absorbed by the charges"; the "zero point field [was] discovered by Planck" (the existence of such a field is disputed)

I will turn this into a Disputed section. 129.118.34.92 (talk) 17:53, 12 November 2019 (UTC)[reply]

Hi, everybody. A derivation of limit cycle oscillations has been achieved from the Liénard-Wiechert potentials and published recently in a high impact factor journal (https://doi.org/10.1007/s11071-020-05928-5). I am the author of the paper, and therefore I am not the person allowed to upload the reference, since a COI is at stake. But perhaps, if somebody finds it interesting, he could help to revive interest in classical field theories by introducing a brief paragraph in the section entitled “Implications”. Something similar to this:

Charged extended particles can experience self-oscillatory dynamics as a result of classical electrodynamic self-interactions \cite{}. This trembling motion has a frequency that is closely related to the zitterbewegung frequency appearing in Dirac's equation. The mechanism producing these fluctuations relies on radiation reaction as appearing in the Abraham-Lorentz force, and arises because some parts of an accelerated charged corpuscle emit electromagnetic perturbations that can affect another part of the body, producing self-forces. Using the Liénard-Wiechert potential as solutions to Maxwell's equations with sources, it can be shown that these forces can be described in terms of state-dependent delay differential equations, which display limit cycle behavior. Alvaro12Lopez (talk) 08:07, 30 September 2020 (UTC)[reply]

[1] A. Malcherek: Elektromagnetismus und Gravitation, Die Vereinheitlichung der klassischen Physik, Springer-Vieweg, 2022, https://doi.org/10.1007/978-3-658-35956-0

[1]