Talk:Lorenz gauge condition

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This page has been temporarily redirected. If the material on this topic grows, it can be brought back into this page. Bambaiah 14:26, Jun 6, 2005 (UTC)

I think this needs to be moved to Lorentz gauge (Wikipedia is not a place to right wrongs.)

None of my textbooks use the term Lorenz gauge for this. Griffiths E&M even has a footnote on page 421 of third edition saying:

"There is some question whether this should be attributed to H.A. Lorentz or to L.V. Lorenz (see J. Van Bladel IEE Antennas and Propagation Magazine 33(2), 69 (1991)). But all the standard textbooks include the t, and to avoid possible confusion I shall adhere to that practice."

Griffiths is 12 years old and is the youngest text I own. But a very quick search on Google seems to confirm that the situation hasn't changed. It is hard to find anyone but wikipedia who uses the term Lorenz gauge.

Wikipedia is not a place to right wrongs. Even if Lorenz invented the gauge, the Lorentz gauge condition is hardly the only equation to be wrongfully attributed. Indeed, attributing the wrong person seems more of the norm than not.

TStein (talk) 20:41, 10 January 2011 (UTC)

Tstein, My understanding of it is that it was the Danish scientist Ludwig Lorenz and not the Dutch scientist H.A. Lorentz who was responsible for it. The Lorenz gauge came about in 1867, shortly after Maxwell's 1865 paper, and I recall reading that Maxwell himself was furious about it, as he believed that Lorenz had totally missed the point and messed Maxwell's work up, especially in relation to the famous derivation of the electromagnetic wave equation in the 1865 paper, which depended upon the Coulomb gauge. H.A. Lorentz (1853-1928) would have been too young at that time to have been involved. Anyway, here is a source which attributes it to Lorenz as opposed to Lorentz. [1]. And also this [2]. David Tombe (talk) 21:47, 10 January 2011 (UTC)

Thanks for those sources! They look quite useful (as is the IEEE source in Griffiths) for the history section.

My main concern, though, is not who the equation is named after. Rather, I am interested in using the same name for it as everyone else, whether that name is Lorentz gauge or Lorenz gauge or the Hockey Puck gauge. I think the information that you stated should be easily and prominently available on the Lorentz gauge page and in limited form as a footnote whenever the Lorentz gauge is introduced in some detail whether on wikipedia or elsewhere on the web or in print. Then, whenever the mainstream science leans enough towards calling it the Lorenz gauge we should move the page to Lorenz gauge. I don't think that time is now and I definitely don't think wikipedia should be the vanguard in this fight or any fight no matter how right it is.

With redirects, I probably shouldn't care too much about this either way. It is frustrating, though, when people start replacing the term 'Lorentz gauge' by 'Lorenz gauge' in articles such as Maxwell's equations. It distracts from the main article and causes confusion when there should be none.TStein (talk) 19:10, 11 January 2011 (UTC)

Tstein, Well certainly if there might be a large number of people who would want to look up information about the 'Lorenz gauge', but who wrongly think that it is called the 'Lorentz gauge', then we do need to provide some kind of re-direct mechanism. Errors of this kind in the literature usually begin at one particular source and then spread. My attitude to such errors is to always ignore them (or to correct them where that is possible) and to carry on operating on the basis of the correct information. As such, I would never do anything to facilitate the propagation of false information. I would always be in favour of re-directs to the correct state of affairs. If wikipedia has any policy that would be such as to give priority to false information over correct information on the basis of some technicality, I would always leave such a policy for somebody else to enforce. I would never do anything to encourage the spreading of the false information and hence to perpetrate the problem. False information is like a virus, and it needs to be resisted. It may not be wikipedia's policy to right great wrongs, but I personally would never play any part in facilitating the perpetuation of wrongs. I would say that since you know that 'Lorenz gauge' is correct, then it's best to leave the problem for somebody else to deal with. David Tombe (talk) 20:27, 11 January 2011 (UTC)

David, It is only false if you expect that the name of an equation represents the person who first came up with it. I view the name of an equation as just a name accepted and promoted by the community that uses it and that sometimes reflects the person who invented it. (Often it does not for historical reasons.) From this perspective to call something the Lorenz force when the community calls it the Lorentz force is false.

You have a strong historical interest and knowledge and I respect that. I agree with your zeal to attribute equations to the right person (when possible to determine who that person is). If this article was primarily about the history of physics I would have no qualms at all. But this article is primarily about how physics is understood today. As such it needs to use the language of today even when that language is not historically accurate. TStein (talk) 23:37, 11 January 2011 (UTC)

Tstein, Let me check out a few more sources and I'll get back to you. David Tombe (talk) 00:21, 12 January 2011 (UTC)

Tstein, OK, I've checked, and Goldstein, Eyges, and Grant and Philipps all use 'Lorentz Gauge'. Hence the problem is more prolific than I had at first realized. So I'll not stand in the way of what you wish to do. David Tombe (talk) 10:27, 12 January 2011 (UTC)

I swear I had replied to this. For what it's worth, I think this article should be located at Lorenz gauge (as it currently is). This is not a case of people thinking Lorentz had something to do with it (as it would be in a Feynman diagram vs Stuckelberg diagram dispute)" it's just a case of a typo propagating itself through history. Sources quite reliably document this (See J. van Bladel (1991). "Lorenz or Lorentz?". IEEE Antennas Prop. Mag. 33(2):69 given as a reference). The misattribution should however be noted in the lead, or at the very least with a note. Headbomb {talk / contribs / physics / books} 04:44, 19 January 2011 (UTC)

Headbomb, Based on what I wrote earlier, I'd also be inclined to leave it as it is. Tstein did however have a legitimate point, but personally I always favour accuracy. And I see that the misattribution has already been noted in the lead. David Tombe (talk) 22:14, 19 January 2011 (UTC)

Let me note that, although Griffith's is a standard book for undergrads E&M, that does not mean there is no error; J.D. Jackson's book (the Bible for graduate-level courses) only use Lorenz gauge (see chapt 6.3, page 240 in 3rd edition). Lorenz gauge is (historically and physically) correct, calling it Lorentz gauge is a common error; I also agree to leave it as it is, with the note in the text explaining the misattribution --169.233.215.95 (talk) 05:04, 28 April 2011 (UTC)

Every text book that I have, including the second edition of Jackson calls it the Lorentz gauge. My textbooks are from the 80s and 90s though. I still feel very strongly the wikipedia is not the place to right wrongs. It maybe, though that enough people are taught the name as being Lorenz gauge today as to justify its movement. I won't challenge this. TStein (talk) 15:35, 5 December 2011 (UTC)

Standardize the title, but include discussion of whatever controversy

The standard name is 'Lorentz gauge'. That Wikipedia of all places would have the name wrong is completely ridiculous. Whatever controversy there is over attribution can be included in a section of the article. You can't just unilaterally change the accepted name of a standard concept in physics--if everyone did this, science would descend into incomprehensible babel. JKeck (talk) 17:00, 13 October 2014 (UTC)

If there is any doubt (and there is not): both the Feynman Lectures and J.D. Jackson (2nd edition) call it Lorentz gauge--it goes along with the Lorentz condition. In neither book even is "Lorenz" even included in the index. JKeck (talk) 17:09, 13 October 2014 (UTC)

I pretty sure my copy of Jackson's book (3d ed?) uses "Lorenz" (with a ref. to an OP), and, as I recall, he points out that it is Lorenz, not Lorentz. YohanN7 (talk) 11:10, 12 July 2017 (UTC)

Lorentz invariance

Surely we need a minus to obtain Lorentz invariance? I have explained this on physicsstackexchange, under "the definition of the Lorenz gauge condition" - tag gauge,

$\nabla \cdot {\vec {A}}-{\frac {1}{c}}{\frac {\partial \varphi }{\partial t}}=0.$ — Preceding unsigned comment added by Stephen William Wynn (talk • contribs) 19:41, 27 June 2017 (UTC)

This is saying the Lorentz divergence of the 4 potential is zero. For Lorentz invariance when calculating the divergence in 4 dimensions, the time component has to be subtracted. — Preceding unsigned comment added by Stephen William Wynn (talk • contribs) 09:53, 28 June 2017 (UTC)

If (T,X,Y,Z) is Lorentz covariant, the elegant equation

${\frac {\partial X}{\partial x}}+{\frac {\partial Y}{\partial y}}+{\frac {\partial Z}{\partial z}}={\frac {1}{c}}{\frac {\partial T}{\partial t}}$

is Lorentz invariant. If there are no complex numbers or minus signs, then time and space have to be on opposite sides of the equation. This is true for example of the heat equation, the wave equation and, the Lorenz gauge condition. 

$\nabla \cdot {\vec {A}}={\frac {1}{c}}{\frac {\partial \phi }{\partial t}}$

Each vector ${\vec {V}}=(T,X,Y,Z)$ has a covector ${\vec {C}}{\vec {V}}=(T,-X,-Y,-Z)$. The derivative :${\vec {D}}=({\frac {1}{c}}{\frac {\partial }{\partial t}},{\frac {\partial }{\partial x}},{\frac {\partial }{\partial y}},{\frac {\partial }{\partial z}})$ has the coderivative :${\vec {C}}{\vec {D}}=({\frac {1}{c}}{\frac {\partial }{\partial t}},-{\frac {\partial }{\partial x}},-{\frac {\partial }{\partial y}},-{\frac {\partial }{\partial z}})$: Then the Lorenz gauge condition is given by ${\vec {D}}.{\vec {C}}{\vec {V}}={\vec {C}}{\vec {D}}.{\vec {V}}=0$.

We can define a Lorentz product of two vectors $(t_{1},x_{1},y_{1},z_{1})l(t_{2},x_{2},y_{2},z_{2})=t_{1}t_{2}-x_{1}x_{2}-y_{1}y_{2}-z_{1}z_{2}.$ That is the dot product of four-vectors. So we get a positive time component and  three negative space components. The Lorenz gauge condition is defined by a Lorentz product, that is the derivative with the four potential. So the definition on Wikipedia is clearly wrong, since the time and space components have the same sign. — Preceding unsigned comment added by Stephen William Wynn (talk • contribs) 12:08, 29 July 2017 (UTC)

It's pretty simple: $\partial _{\mu }A^{\mu }=\left({\frac {1}{c}}{\frac {\partial }{\partial t}},{\vec {\nabla }}\right)\cdot \left({\frac {\phi }{c}},{\vec {A}}\right)={\frac {1}{c^{2}}}{\frac {\partial \phi }{\partial t}}+\nabla \cdot {\vec {A}}=0$. I believe you're confusing $\partial _{\mu }$ with $\partial ^{\mu }$. — dukwon (talk) (contribs) 13:01, 3 October 2017 (UTC)

On the contrary:

$\partial _{\mu }A^{\mu }=\left({\frac {1}{c}}{\frac {\partial }{\partial t}},{\vec {\nabla }}\right)\cdot \left({\frac {\phi }{c}},{\vec {A}}\right)={\frac {1}{c^{2}}}{\frac {\partial \phi }{\partial t}}-\nabla \cdot {\vec {A}}=0$ where we have the dot product of four-vectors with Minkowski signature (+---). — Preceding unsigned comment added by Stephen William Wynn (talk • contribs) 16:16, 3 October 2017 (UTC)

You're adding a minus sign for no reason. I still think you're confusing $\partial _{\mu }$ with $\partial ^{\mu }$. The Lorenz gauge is $\partial ^{\nu }\eta _{\mu \nu }A^{\mu }=0$, where $\partial ^{\nu }=\left({\frac {1}{c}}{\frac {\partial }{\partial t}},-{\vec {\nabla }}\right)$ with the (+---) signature. — dukwon (talk) (contribs) 16:59, 3 October 2017 (UTC)

Actually, my suspicion seems to be confirmed in the above where you define "${\vec {C}}{\vec {D}}$" (i.e. $\partial _{\mu }$ in more conventional notation). It has the wrong signs. — dukwon (talk) (contribs) 17:05, 3 October 2017 (UTC)

I think I have seen the light. I have been wrong to say the definition of the Lorenz gauge condition should contain a minus. The use of upper indices for the four potential I find very confusing. But it is a convention we have to live with. Stephen William Wynn (talk) 16:25, 19 October 2017 (UTC)