Talk:Classical electromagnetism

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Classical electrodynamics is the right title --Lucinos 07:51, 20 September 2005 (UTC)

Template:Electromagnetism vs Template:Electromagnetism2

I have thought for a while that the electromagnetism template is too long. I feel it gives a better overview of the subject if all of the main topics can be seen together. I created a new template and gave an explanation on the old (i.e. current) template talk page, however I don't think many people are watching that page.

I have modified this article to demonstrate the new template and I would appreciate people's thoughts on it: constructive criticism, arguments for or against the change, suggestions for different layouts, etc.

To see an example of a similar template style, check out Template:Thermodynamic_equations. This example expands the sublist associated with the main topic article currently being viewed, then has a separate template for each main topic once you are viewing articles within that topic. My personal preference (at least for electromagnetism) would be to remain with just one template and expand the main topic sublist for all articles associated with that topic.--DJIndica 16:49, 6 November 2007 (UTC)

What happened to the old Electrodynamics article?

The redirect appears to have lost all the good material that existed in the old article. The new article seems to be missing much of the layman's terms descriptions of electrodynamics and is now overly technical to the point of unintelligible to the average user. IE, me... Can someone please restore the old content to the new page, or else restore the old page? The new page is "less good" than the old one. 64.122.15.114 (talk) 22:53, 24 July 2008 (UTC)

Didn't it used to note that electrodynamics was the study of the motion of charges particles, generally in circuits (IE, electric currents and their associated magnetic fields)? As opposed to electrostatics which is the study of charges more or less at rest with respect each other (IE electric fields and their relationship to clouds of charge)? 64.122.15.114 (talk) 23:01, 24 July 2008 (UTC)

Electrodynamics @ Answers.com. Several various references all agree on the above point(s). 64.122.15.114 (talk) 23:05, 24 July 2008 (UTC)

Are you referring to this old article? This is the "electrodynamics" article as it existed immediately before being made into a redirect, which was way back in September 2004. Or are you thinking of something different? --Steve (talk) 01:53, 25 July 2008 (UTC)

That article should be incorporated, rather than dropped. I am particularly uncomfortable with the statement that electrodynamics is a "theory". Electrodynamics was a branch of classic physics and is still widely taught as a branch of classic physics, with both empirical laws and mathematical treatments. Classical electromagnetism as an undergraduate title usually puts even more emphasis on the empirical aspects. Sillyvalley (talk) 09:14, 18 September 2008 (UTC)

Whew! Isn't Classical Physics a theory? (As opposed to Creationism, for instance, which is another theory.) Indeed, as you imply, as well as the mathematically derived theories, Classical Physics includes the theory of deriving "empirical" laws that can correctly extrapolate empirical measurements. Keithbowden (talk) 21:28, 1 December 2008 (UTC)

I took out the following paragraph from the basic description of electric fields, which I think is quite inappropriate at this point in the discussion: "(As a side note, by using the appropriate gauge transformations, one can define V to be zero and define E entirely as the negative time derivative of A, however, this is rarely done because it is cumbersome and, more importantly, it no longer satisfies the requirements of the Lorenz gauge and hence is no longer relativistically invariant). " Gaenciso (talk) 18:44, 18 April 2009 (UTC)

Hi. Sorry, but what is the basic high-school education (or less) reader supposed to understand from all this? I now know nothing more about classical electromagnetism than I did before reading the article, except that it can be expressed by throwing together a bunch of theories I have never before heard of. I'd like to work it out, I would, I even have a chintzy bachelor's degree, but this is too technical for me. Chaim1221 (talk) 05:41, 10 August 2010 (UTC)

Agreed, this article is lacking a good summary and introduction, and seems to be more of a list of topics. I've added some qualitative description of the Lorentz force, and could probably do the same for some of the other topics, but I think this article could use a better introduction and organization, which I'm not sure I could write at the moment. Disphenoidal (talk) 21:07, 15 October 2010 (UTC)

New sections or references needed

This article and closely related articles such as Electromagnetism and Maxwell's equations omit mention of how straightforward concepts like energy density, momentum density, pressure etc. are related to field strength. I had to find articles not referenced (even indirectly as far as I could tell) such as Poynting vector and |Energy density to locate any mention thereof. I think it is pretty reasonable to expect these everyday concepts to be mentioned in this article or a closely related one, with at least direct links to articles in which the respective formulae appear. Quondum (talk) 07:21, 30 September 2011 (UTC)

Needs significant clarification

The "introduction" reads like a poor attempt at denigration of the theory and it's proponents, rather than explaining what Classical Electromagnetism actually is. There are also far too many unexplained assumptions stated, especially with reference to deriving equations not linked to or explained in any meaningful way. They are just presented ex-post facto, with no context or reference. This has to be one of the most confusing (and condescending) physics articles I've read so far. The Lorentz force description is pretty clear and helpful, but everything else looks like it was pasted out of student notes. Simply removing a unit vector from an equation with 10 or so other undefined variables doesn't make the equation less "cumbersome", it just makes the writer seem smarter than the reader. This doesn't help to explain anything about the equation in the first place. I mistook this article for a spoof until I realised it was trying to be serious. And I come from a fair-to-middling physics background. Someone looking for clarification about electromechanics without high-level math skills, or without a degree, would just be put off. Unfortunately, I don't have the technical skills to fix this hole. I'd be happy to collaborate with someone who did, though. Cephas Borg (talk) 13:18, 7 December 2011 (UTC)

This article needs major work!

This entire article needs major work. The article on Maxwell's equations is excellent and is what I was expecting to find when I came to this article. However, I realize that it's pointless to duplicate all the material in the Maxwell's equations article and put it into this article. As a result, this article should be very short and serve mostly to redirect the reader to the Maxwell's equations article. However, the two items of classical electrodynamics that are not strictly part of the Maxwell's equations, the Lorenz force law and Newton's laws, should be mentioned in this article. Perhaps a list with very short descriptions of the concepts contained in classical electromagnetism belongs in this article, that then redirect the reader to other pages to learn more. The term "classical electromagnetism" is a high level term that embodies a huge field of phenomena. As a result, I believe this article should have a high-level, descriptive tone (no equations) and then link to other pages heavily. 129.63.129.196 (talk) 17:58, 4 December 2012 (UTC)

How are Newton's laws related to electrodynamics? I understand Newton's law particularly the second which takes the form of a differential equation of time and position can be used to describe physical systems but how should this be related to electricity and magnetism? What part of the article should Newton's laws be added? ScientistBuilder (talk) 14:48, 9 February 2022 (UTC)

The more I have thought about it, the more I think this article is so bad it should be scrapped and started over from scratch. I propose that the this article should have the following sections

• Fundamental Equations of Classical Electromagnetism: Mention Maxwell's equations, Lorenz force law, and Newton's laws, with a short description of teach, then link to the relevant pages for more info.
• Dynamics vs. Statics: A brief description of the difference between electrodynamics and electrostatics/magnetostatics, when each is applicable and what Maxwell's equations reduce down to in statics.
• Relationship to Other Theories: Describe how classical electromagnetism automatically contains special relativity, but is only an approximation of quantum electrodynamics.
• Subfields: List the mains subfields with short descriptions of each, such as electronics, magnetics, radiation, scattering, waveguides, optics
• Applications: Describe everyday applications
• History: A brief history with a main link to the full history article

129.63.129.196 (talk) 18:21, 4 December 2012 (UTC)

I have started working on a section for applications. ScientistBuilder (talk) 14:45, 9 February 2022 (UTC)

Electromagnetism vs QED

I thought that QED was more applicable at high field strengths in the introduction: "For small distances and low field strengths, such interactions are better described by quantum electrodynamics." ScientistBuilder (talk) 14:55, 9 February 2022 (UTC)