User talk:E4mmacro

From Wikipedia, the free encyclopedia

Welcome!

Hello E4mmacro, and welcome to Wikipedia! Thank you for your contributions. I hope you like the place and decide to stay. Here are a few good links for newcomers:

I hope you enjoy editing here and being a Wikipedian! Please sign your name on talk pages using four tildes (~~~~); this will automatically produce your name and the date. If you have any questions, check out Wikipedia:Where to ask a question or ask me on my talk page. Again, welcome! 

Contents

[edit] Edit summary

When editing an article on Wikipedia there is a small field labelled "Edit summary" under the main edit-box. It looks like this:

Edit summary text box

The text written here will appear on the Recent changes page, in the page revision history, on the diff page, and in the watchlists of users who are watching that article. See m:Help:Edit summary for full information on this feature.

When you leave the edit summary blank, some of your edits could be mistaken for vandalism and may be reverted, so please always briefly summarize your edits, especially when you are making subtle but important changes, like changing dates or numbers. Thank you. – Oleg Alexandrov (talk) 02:25, 15 December 2005 (UTC)

[edit] History of science

Please consider joining the History of Science WikiProject.--ragesoss 18:44, 22 January 2006 (UTC)

[edit] Henri Poincaré

An anon is doing some suspicious looking stuff with this article and since you seem to have an interest there and at least have an account, I thought I'd ask your take on it. Is he a vandal or does he have a serious case for removing the headers and POV tags? --DanielCD 22:11, 27 January 2006 (UTC)

If you can, give that guy a little space to vent. I don't know what's going on at that article, but it sounds like no one is communicating. I'm going to check back later, so if you could, give me a brief outline of what's going on at my talk page so I'll have something to go on. Thanks. --DanielCD 22:39, 27 January 2006 (UTC)
As per the discussion at the article, please LMK your take on this. Why do you want the POV tags? I just want to know your reasoning and what you are thinking so I can help. --DanielCD 01:16, 28 January 2006 (UTC)

[edit] Relativity of simultaneity

Hi Michael,

I am near completion of writing stuff for the relativity of simultaneity article. You have done a lot of editing to that article, so presumably you are still watching that article.

What I have written is along similar lines as what I wrote on the relativity of simultaneity talk page, but for the article I have written less technical, avoiding jargon and such.

When my write up is finished I will edit the relativity of simultaneity article. --Cleonis | Talk 18:28, 1 February 2006 (UTC)

[...]I actually created (not just edited) the page with the idea of showing one thing that I thought was not well known. [...] E4mmacro 21:45, 1 February 2006 (UTC)

Yeah, I know you created that article, I went all the way back in the history and I saw you had started it. That is why I contacted you. Here is what I will do. I will finish the write up, I will do an edit, and I will immediately revert. That way my edit is in the article history, so you can compare and comment on it. (What I have written probably needs trimming down, I'm not very good at that.) --Cleonis | Talk 22:33, 1 February 2006 (UTC)

[edit] d'Alemberts principle

Hi Cleonis, by a strange quirk of fate I had never actually taught our (rigid body) dynamics classes until last year. I am a big fan of d'Alembert's principle (add the "inertial forces" and "inertial torques" to the system and then treat it as a statics problem - i.e. put one's self in a reference frame attached to the rigid body, which is undergoing linear accleration as well as angular accleration). I notice some of the text-books express a similar idea to yours about inertial forces. They really hate them. [...] E4mmacro 22:04, 1 February 2006 (UTC)

Hi Micheal,

When it comes to performing calculations, then simply everything that yields the correct answer is fine. In performing calculations only two things matter: whether the final answer is correct, and how effecient the calculation is. (So when a phial with a suspension is spinning rapidly in a lab centrifuge, then of course a calculation of the processes in the phial treat it as a statics problem. If the lab centrifuge is pulling a 1000 G's, then that is the effective force towards the bottom of the phial.)

The elasticity of the spring is such that the centripetal force is proportional to the distance to the axis of rotation
The elasticity of the spring is such that the centripetal force is proportional to the distance to the axis of rotation

In teaching principles of physics the demands are quite different as compared to teaching calculational agility. The strength of a theory is in the ability to organize the perceptions into a coherent picture. The strength of newtonian physics is that the understanding of physics taking place is organized around the concept of inertia and inertial motion.

I think that what is depicted in the animation to the right is straighforward to understand in terms of a single force, the centripetal force, and inertia.

I think it is wrong to even try and understand it as a statics problem. Please check out the article I wrote about it Rotational-vibrational coupling. Very much related is the article about the physics of a rotating mercury mirror . My assessment is that attempts to understand the dynamics of a rotating mercury mirror in d'Alembertian terms leads to self-contradiction.

Can you point out to me places where I can find information about d'Alembert's principle? I want to make sure whether I have the right picture in mind. --Cleonis | Talk 01:34, 2 February 2006 (UTC)

I think there is more than one principle of d'Alembert, but:
I can give you my interpretation of it in a tiutorial I set: http://www.mech.uq.edu.au/courses/mech2210/dynamics_2d/Dalem.pdf with the following answer to the first (most difficult question): http://www.mech.uq.edu.au/courses/mech2210/dynamics_2d/Dalem_ans.pdf I sure hope I was right!
Pages 6-9 of the following lecture notes introduces d'Almebert's principle, http://www.mech.uq.edu.au/courses/mech2210/dynamics_2d/lect1.pdf and the example of the aircraft on the runway comes from a textbook (mentioned) which did approve of d'Alembert's principle). E4mmacro 07:53, 2 February 2006 (UTC)

Clearly, the examples show that d'Alemberts principle is an important asset in the physicists mathematics toolkit.

By the way the example with the water flowing through a bend in a tube can possibly also be seen as an application of the principle of conservation of momentum. What happens if the tube is not well secured?

Let me try some ASCII art
| |
\ \______   _______ 
 \_______( )______ \   
                  \ \
                  | |
the garden sprayer swivels when it is squirting water.

In order for the water to change direction in the bend, the tube would have to exert a force on the water, but the tube is free to swivel. Interestingly, the actual action is not at the nozzles. The action, causing the sprayer to swivel is in the bend.

Returning to d'Alembert's principle, as you can see from what I wrote earlier, I draw a sharp distinction between principles of physics and calculational strategies. Following that I object in cases where concepts from calculational strategies are presented as physics principles. As I wrote before, any calculational strategy that yields the correct answer efficiently is fine by me. --Cleonis | Talk 12:44, 2 February 2006 (UTC)

I think I neeed to explain a bit more. It is of course no coincidence that d'Alemberts principle is so effective, many have pointed out that it is related to the equivalence of inertial and gravitational mass. In the theory of general relativity the description of inertia and the description of gravitation are unified into a description of a single entity. My understanding is that a distinction between inertia and gravitation is not present in the mathematical structure of the equations of general relativity. In the modern interpretation of general relativity, gravitation is associated exclusively with space-time curvature, and that is the general relativity interpretation that I follow. --Cleonis | Talk 09:00, 4 February 2006 (UTC)

[edit] Effective gravity and true newtonian gravity

I copy and paste from the Talk:Relativity of simultaneity page.

[...] Is this the same or similar to saying the effective gravity force (i.e. Newtonian - minus the centrifugal force) is the same everywhere on the Earth's surface? Because the Earth deforms until this condition is met. [...] E4mmacro 06:32, 7 February 2006 (UTC)

Well, there must be more to the story than that:

gravitational acceleration at poles = 9.8322 m/s^2
gravitational acceleration at equator = 9.7805 m/s^2

The centripetal acceleration at the equator is v^2/r
The velocity of co-moving with the Earth at the equator is 465 m/s
The Earth's radius at the Equator is 6378 kilometer
The centripetal acceleration of co-moving with the Earth at the Equator is 0.0339 m/s^2

So the numbers don't add up. The effective gravitational acceleration at the Equator is 9.7805 m/s^2, hence the true newtonian gravitational acceleration at the Equator is 9,7805 + 0.0339 = 9.8144 m/s^2
That is a long way short of the 9.8322 m/s^2 at the poles.

Methinks the approximation with a centrifugal force only works when the deviation from a perfect sphere is negligable, and with Earth that is not the case. --Cleonis | Talk 13:50, 7 February 2006 (UTC)

[edit] The tsunami effect

Thanks for sending me the e-mail message regarding the stunami effect. As you probably have read, bainer suggested that the anonymous IPs obtain accounts. When they do so, we should be better able to achieve consensus (even if it requires WP:MEDCAB or a user RfC). It will then be time to unprotect the page. How does that approach sound? The Rod 20:52, 12 February 2006 (UTC)

Yes it all irrelevant to the Poincare page and the consensus wants it moved elsewhere. If the page is unportected 66/69/Licorne will re-insert the disputed section. He sends me threatening emails telling me this. I suggest that you freeze the discussion page as well. It is pointless talking to him. Can we just freeze everything, ignore him and hope he goes away? E4mmacro 23:59, 12 February 2006 (UTC)
A better approach is probably to treat 66/69 like other POV warriors who come here. That is, encourage them to register for accounts and then engage them directly in conversation outside of the imagined battleground (the article and its talk page). Since Licorne registered immediately after bainer and I invited 66/69 to do so, and since Licorne jumped right into the talk page with the same editing style as 66/69, Licorne seems very likely to be our warrior. So, hopefully we can help that editor understand what Wikipedia is not and, only if that fails, move to more drastic actions. Thanks for your participation in this dispute and for helping keep Wikipedia neutral.
If an editor is threatening you via e-mail, the appropriate first reaction is to attempt to have the editor desist through his or her talk page. Persistent harassment is grounds for a User-conduct RfC. A suggestion is to copy the offending e-mail message to the editor's talk page and to declare that you will ignore subsequent e-mail you from him or her. Then, if your e-mail software supports it, create a spam rule to delete incoming mail from that editor. We must not let attacks push away good editors like you. Peace. The Rod 01:59, 13 February 2006 (UTC)
Note, the above suggestion pertains to threats made in e-mail messages. The primary goal is to appeal to the editor making the threats to stop doing so. When making such an appeal to an editor's talk page regarding his or her threats in talk page posts, it is usually better to refer to the threatening post by pasting the link to it from the talk page history (like I did in the the "this edit" link below). Please let me know whether that is clear. The huge number of posts to the Henri Poincaré talk page makes it difficult for anyone to review the material quickly. I hope to avoid creating more such clutter elsewhere. The Rod 16:08, 14 February 2006 (UTC)
Not quite sure I understand since I didn't add anything to the Poincare page or increase its clutter. I removed my list of insults from Licorne's page and put it here, assuming I can clutter my own page? Licorne has given up emailing me, so that is something. E4mmacro 20:16, 14 February 2006 (UTC)
Please excuse my ambiguity. I did not mean to imply that you cluttered the Henri Poincaré talk page, but rather that the talk page has many personal attacks, original research posts, and reiterations of belabored points, none of which help advance the Henri Poincaré article.
You are more than welcome to keep the list of that editor's attacks on any of your own pages. For brevity and ease of referring to the original posts, however, you may want to consider listing links to the posts instead of the post content. For example, instead of listing "To Michael Macrossan: Wipe your nose ... 69.22.98.162 21:28, 25 January 2006 (UTC)", you can list this: 69: Wipe your nose. Links to the original posts are better references, because the Wikimedia software shows that the post really was made by the referenced editor. The Rod 21:53, 14 February 2006 (UTC)
FYI, this edit was to the editor's main user page, which the editor may not notice. To leave a more visible message for the editor, post your message to User talk:Licorne instead. Doing so will cause the "You have new messages" notice to appear to the editor. Also, note that even if the editor deletes your post, the permanent record of your exchange will be in the talk page history, clearly visible if required at a later date. Please let me know if any of this is unclear. The Rod 06:41, 13 February 2006 (UTC)

[edit] A record of insults

As part of a possible case to show an editor consistently violates Wikipedia protocol, I have been advised the evidence has to be gathered together. So here is a list of insults (of Michael Macrossan only) from 66/69/Licorne. Some have been struck through by the administrators. All remain on the page as of today. Some are borderline between insults and badgering (or attempted intimidation) so I have grouped them under three headings. E4mmacro 23:31, 13 February 2006 (UTC)

[edit] Insults

To Michael Macrossan: Wipe your nose ... 69.22.98.162 21:28, 25 January 2006 (UTC)

I think it is Michael Macrossan who is censoring Wikipedia, because he can supply no sources for his arguments, just like the Inquisition ! 69.22.98.162 22:11, 27 January 2006 (UTC)

To Daniel: Can you please REMOVE Macrossan from this page before he does any more damage ? -He is a madman. 69.22.98.162 04:23, 29 January 2006 (UTC)

SHAME on you Michael Macrossan ! -- I have produced three published world experts against whom you can produce no counter-arguments, so you propose mob rule and a lynching ! Shame on you ! 66.194.104.5 22:38, 8 February 2006 (UTC)

To Macrossan: Aren't you embarrassed - you pretend to be an intellectual but can produce no counter-arguments - you are like the MEDIEVAL WITCH BURNERS OF THE INQUISITION, now aren't you ! 66.194.104.5 23:12, 8 February 2006 (UTC)

Macrossan, you cannot count ? ? 69.22.98.146 20:47, 9 February 2006 (UTC)

I agree, Mavrossan is funny, why is he so pig headed ? 69.22.98.146 21:30, 9 February 2006 (UTC)

I see Macrossan has no real comment here, interesting. 69.22.98.146 21:15, 9 February 2006 (UTC)

Change it ? -- You mean CENSOR it. -- Thank God it is protected from you Macrossan. 69.22.98.146 14:30, 10 February 2006 (UTC)

Macrossan has a history of disappearing when he is out of arguments. 69.22.98.146 13:43, 10 February 2006 (UTC)

What do you mean Macrossan, you didn't understand a word he said. 69.22.98.146 02:53, 11 February 2006 (UTC)

Macrossan you are incompetent to write on Physics matters. Licorne 13:53, 12 February 2006 (UTC)

Macrossan, Why does a Common Fact Frighten you so? - - Coward CAN'T answer.Licorne 05:13, 13 February 2006 (UTC)

Macrossan has a well established history of disappearing when he has no answers. Licorne 05:30, 13 February 2006 (UTC)"

Whenever Macrossan is stuck he goes a hiding. -- 69.22.98.146 22:04, 13 February 2006 (UTC)

[edit] Badgering

Put it all back, Michael Macrossan, I am waiting.... 69.22.98.162 23:35, 27 January 2006 (UTC)

To Michael Macrossan: You vandalized this page, now Go back to the original Table of Contents how it was. 69.22.98.162 05:27, 28 January 2006 (UTC)

I don't want to have to repeat this again, understood, Macrossan ? 69.22.98.162 12:55, 29 January 2006 (UTC)

To Macrossan: NEVER AGAIN insert YOUR debate of 1906 vs 1905 into wikipedia

Tatoo it to your forehead Macrossan. 69.22.98.162 20:05, 30 January 2006 (UTC)

To Michael Macrossan: WHY does a simple fact that can be found in every bookstore in America frighten you so ? --Licorne 03:16, 13 February 2006 (UTC)

[edit] Insult and badgering combined

To Macrossan … do NOT add it to the article -- it is something just in YOUR little mind. 69.22.98.162 13:18, 30 January 2006 (UTC)

To Macrossan: … it is ONLY disputed in YOUR little mind, so do NOT insert it into wikipedia … WHO are YOU to dispute Whittaker. -- Stop vandalizing Wikipedia.69.22.98.162 13:42, 30 January 2006 (UTC)

I guess I did provoke this one [this one] but it is worth recording a new IP address: 17.255.240.78 is just as sensitive as Licorne about any criticism of Licorne. Well not exactly a new address, it is the IP address which voted to retain the irrelevant last section on the Poincare page. E4mmacro 02:32, 15 February 2006 (UTC)

E4mmacro 23:31, 13 February 2006 (UTC)

[edit] Einstein/Whittaker

Thanks for your explanations on the Einstein page about Whittaker's lapses re: Poincare. Very helpful. Lucidish 22:43, 12 February 2006 (UTC)

Any info, including that article you mention wanting to write, would be supremely helpful. I plan on using this topic as an essay for one of my classes, and my having a limited science background means that I'm indebted to anyone who shed insight on the issue. Lucidish 21:20, 16 February 2006 (UTC)

[edit] RFC

If you wanted to file an WP:RFC against our mutual friend, I'd be happy to contribute to it. Just a thought, if you are getting weary of it. He's definitely over the line on a number of Wikipedia policies (WP:NPOV, WP:CITE, WP:NOR, WP:NPA) and has shown himself to be unable and unwilling to negotiate in a true sense. --Fastfission 01:24, 15 February 2006 (UTC)


[edit] Einstein POV-pusher

Hi there. I've decided that this has all gone far enough and it is pretty clear that the POV-pusher on the Einstein/Poincaré/Hilbert pages really does have nothing to contribute and is doing nothing but wasting a lot of time. I'm compiling evidence for a RFC and probably eventually an ArbCom case, with the specific assertions that the user has 1. been engaged in rampant POV-pushing and intellectual dishonesty, and 2. been badgering and insulting other Wikipedia editors. Unfortunately compiling the evidence is very time consuming, given that it is spread out over many pages, different accounts and IP addresses, and involves sorting through dozens of diffs. If you want to take a look at it, and contribute anything you are able to, the temp page I am doing this on is User:Fastfission/RFC. Thanks for your time! --Fastfission 19:42, 15 February 2006 (UTC)

Ok. I will look at it, on the weekend and see what I can add. You did the right things. E4mmacro 20:57, 15 February 2006 (UTC)

  • Also, one other thing: when posting specific examples, it is very helpful to post the "Diff links (in the way that I have) which document exactly when the change was made. It is very tedious work, though, so if you don't get to all of them I'm happy to try and sort through them and figure out which ones they were. --Fastfission 20:59, 15 February 2006 (UTC)
Sorry Rod! I ruined your simple question to Licorne about 2 IP addresses. Tecnically we don't know if "STOP MAKING FALSE ACCUSATIONS" refers to me (where I listed five IP addresses), or to you, who asked him about two IP address. I should know better by now. Sorry once again. E4mmacro 08:30, 16 February 2006 (UTC)
No worries. It's clear enough to me from that this post was a reply to my question. The Rod 18:58, 16 February 2006 (UTC)

Here Licorne shows clearly why he cannot offer a NPOV towards Einstein, and therefore has little to offer wikipedia. According to Licorne Einstein can only plagarise or be wrong (always). How could "always wrong" be true - even Licorne himself is not "always wrong"? How could anyone think that any scientist who published as much as Eisntein could "always" be wrong. E4mmacro 01:46, 24 February 2006 (UTC)

[edit] RFC

I've opened a Request for Comments about the editing behavior of User:Licorne at Wikipedia:Requests_for_comment/Licorne. I didn't mean for the attacks against you to get such a high visibility in this, but since you had already documented them it was the easiest way of doing it! I hope that is okay with you. --Fastfission 17:33, 17 February 2006 (UTC)

I don't mind. E4mmacro 20:05, 17 February 2006 (UTC)
I think, in the RFC page you mis-state his POV. It is not Poincare and Lorentz who he thinks discovered relativity - it is Poincare only. He misquotes Whittaker as crediting Poincare only (when Whittaker credits Poincare and Lorentz). He tried for a while to credit General Relativity to Poincare, because Hilbert was a friend of Poincare's and travelled to a conference with him - i.e. Hilbert got all the essentials of GR from Poincare failed theory of gravity. THis was too much, even for him to maintain against the evidence. E4mmacro 20:16, 17 February 2006 (UTC)

[edit] Question about the understanding of special relativity

E4mm, since you know what you're talking about :-) .... I am a bit puzzled about the way E=mc2 is presented in various Wikipedia articles and other references - it seems to understate the radical nature of Einstein's interpretation. I tried to encapsulate my puzzlement into a question at Talk:Special relativity. I'd appreciate your feedback. --Alvestrand 09:25, 18 February 2006 (UTC)

Maybe we all have too familar with energy/mass equivalence. de Kludde and Licorne assert that "obviously" Poincare, once he had the momentum of radiation, somehow knew this meant mass/energy were interchangeable, he just never mentioned it. The fact that I had to go to some trouble proving Poincare did not know this seems to show that we are a bit puzzled why this "easy step" was not taken by Poincare.
Harald88 might take you or me to task if we loosely suggest that mass and energy are the same thing; I think the meticulous thing to say is that the two conservation laws of newtonian mechanics, that of mass and that of energy, are now replaced by a single "conservation of mass-energy".
I am not sure if that answers your question.

My impression of the 1800s in science is that energy and mass were regarded as totally different concepts - I'm pretty confident their unification was seen as revolutionary.... I'll ask Harald88 to take a look too.... --Alvestrand 21:27, 18 February 2006 (UTC)

[edit] Some more thoughts

I agree with you - it was a radical thing to say, and I know of no derivation of Einstein's E = mc^2 which does not rely on variation of mass with velocity in the Lorentzian way. This was the bit lacking, or not accepted until Lorentz 1904.

On the other hand, perhaps energy-matter equivalence appeared at the time as the next logical step. It was known that radiation had momentum. Starting form Maxwell's radiation pressure. Various analyses had been done with Maxwell's equations showing that if you took a hollow container filled with radiation and tried to move it, Maxwell's radiation pressure on the inside meant it would have or appear to have a greater inertia that that of the mass of the container only, and the extra inertai was E/c^2. Meanwhile, it was known that electric charges were similarly more difficult to accelerate that you might expect because of the phenomenon of "self inductance" (a moving charge is a current, currents induce forces resisting changes in the current). In a few places, Poincare wonders whether Lorentz's variation of mass with velocity means that that ALL inertia (of the electron) is electromagnetic in nature. Kaufmann in about 1902/3 had experiments of moving electrons, trying to detect the mass/charge ratio, and it seemed for a while that the (real) mass of the electron might be zero and its inertia was all electro-magnetic. So there were various hints. The aether theorists had suggested matter mass) was somehow "condensed aether" (or a "knot" in the aether, or a vortex in the aether) and hence connected to electromagnetism. I think it was Helmholtz who had a fluid aether, and the extra inertia of a moving body was associated with the vortex wake behind it (in ordinary fluid mechanics this wake is a low pressure region behind the body and there is a high pressure region in front of the body, the pressure difference gives drag force and the drag force is proportional to velocity^2). Hence the moving body appears to have greater inertia as it moves faster (loosley it drags along a bigger wake, it drags with it a bigger junk of aether). All these ideas may have made it seem E = mc^2 was a natural result.

The extension to ANY form of energy was a big big step. I still am trying to get a full grip on the statement in Einstein 1905 that it makes no difference to his analysis that the energy lost was radiation (ie it could be lost as heat by conduction). But this is similar, I think, to the neat way Einstein concludes in the preceding 1905 relativity paper that variation of mass applies to all mass, not just a moving electron, because Maxwell-Lorentz theory and the relativity theory applies to any body provided it has any electric charge, and so one can make the charge arbitrarily small, i.e. in the limit of zero charge the theory applies. E4mmacro 21:40, 18 February 2006 (UTC)

[edit] User:De kludde

Something I stumbled across today: User:De kludde at the "White Nationalist Wiki". Just in case anybody had any doubts about motivations. --Fastfission 16:17, 18 February 2006 (UTC)

  • He also is the one who wrote the "About" section of the WN Wiki, stating that its purpose is " to provide a wiki which is free from the strong Jewish bias dominating the classical Wikipedia". Ugh. --Fastfission 17:50, 18 February 2006 (UTC)
  • Ok, thanks. That clears up something that was puzzling me. E4mmacro 20:36, 18 February 2006 (UTC)
  • Omigod. I skimmed some of the wnwiki pieces. E4mmacro 20:44, 18 February 2006 (UTC)
  • Why, I never tried to keep my motivations secret. After all, I could have chosen a different user name on this wiki. I just wonder why my (or Winterberg's) motivation is being discussed, while no one seems to care about the political motivations of Renn, Stachel and their followers. Do you (or e4mmacro) really want to defend the view that they have no political motivation?De kludde 09:07, 26 February 2006 (UTC)

It was my mistake - you didn't try to fool me. My comment omigod referred to many wnwiki pieces, not just that on Einstein. As I remember it the Einstein article introduction was laughable in the extent of personal attack it stooped to. Other articles on wnwiki seemed obviously anti-semite. Now that I have read wnwiki's statement of principles (or whatever) I am better informed. E4mmacro 20:33, 26 February 2006 (UTC)

[edit] Licorne-baiting

Licorne's not bending one inch. In fact he's been growing more hysterical. I've added quite a few comments to his statements today - probably increasing his blood pressure by a bit. I'm not entirely sure if it's useful - but at least it makes sure his "last word" isn't the last word on the talk pages.

I'm kind of thinking that today I've got the energy to contradict him, tomorrow you may have some... there are more of us than there are of him, and sooner or later he'll give up. Do you think that's hopelessly optimistic? --Alvestrand 22:22, 19 February 2006 (UTC)

... and there's some hope; his latest addition of Hilbert to the Einstein page is almost defensive in tone; I didn't find reason to revert it this time around.... --Alvestrand 23:01, 19 February 2006 (UTC)

My view is he will never give up, and I decided sometime ago that letting him have the last word isn't so bad. Anything he says is tranparently silly, whether it is the first or last word. But, when I have the energy I sometimes answer him. Thanks for your efforts. E4mmacro 04:36, 20 February 2006 (UTC)
  • Thought you might like to know that in the end, Licorne's just a petty anti-Semite of the most boring and vulgar variety. Check out User_talk:Licorne#Personal_attacks_2 if you're in the mood to read something pathetic. --Fastfission 01:08, 14 March 2006 (UTC)
  • Yes. Pathethic. I bet he comes back somehow. E4mmacro 05:27, 14 March 2006 (UTC)

[edit] Edmund Whittaker's credibility

Hi Micheal,

have you read Kevin Brown's review of Whittaker's book A History of the Theories of Aether and Electricity? Possibly you have, your caution towards Whittaker seems to indicate so.
Kevin Brown's review

Kevin Brown finds himself forced to the conclusion that at some points Edmund Whittaker stoops to sheer dishonesty. Kevin Brown points out that in many places Whittaker employs suggestion to steer the reader into erroneous conclusions. In some respects Whittaker seeks to disinform the reader, that is how I understand the book review. --Cleonis | Talk 14:23, 2 March 2006 (UTC)

Thanks, Cleonis. I hadn't read any particular review of Whittaker, but had heard somewhere that his book was controversial when published. I also read somewhere that Max Born tried to convince Whittaker to change it before publication to give proper credit to Einstein (this is why books are much less authorative than journal papers in my view - Born cannot insist he makes the change). I think perhaps that over-stating his (Whittaker's) case might be an understandable reaction in 1953 when the history of pre-Einstein relativity may have been completely forgotten. I guess the book did have an effect on Born, who wrote the quote I put into the poll on the Einstein talk page - saying Einstein's 1905 was the key stone in an arch built by Lorentz Poincare and others. I think the general view in 1953 was that SR had popped out of nowhere in 1905, but I could be wrong. Ives's (and Stilwell) experimental verification of time dilation (an extraodinary careful and clever piece of work in my view) was forgotten, probably because he said he was verifying Larmor's prediction 1897). When I read Ives and Stilwel I was amazed that I had never heard of it, and the first experiment quoted in support of time dilation was the meson decay one, which seemed to me less direct (a matter of opinion). I mention Ives because I think Whittaker was influenced by Ives, particularly the latter's e=mc^2 paper. E4mmacro 17:40, 2 March 2006 (UTC)

On reading Brown's review, Cleonis, I recognize bits of it. I must have read it before, so I was wrong to say I had not read it. I don't really know how common this is (is it just me?) but I think it is very common for people to forgot who told them what and later reproduce the idea as their own. This is very true of discussions at conferences. Neither side is really listening to the other (just waiting to say their bit), but each is capable of reproducing later what the other said and being completely convinced they were never told of it. There is an interesting letter from Einstein to Schordinger where Einstein displays exactly this trait (which I think is fairly normal). Schrodinger had sent Einstein his first 4 papers on wave-mechanics for comment. Einstein wrote back some time later, saying that Schrodinger's wave equation was wrong and Einstein quoted the wrong equation. He then wrote what it should be (how it should be corrected). The first equation was Einstein's faulty memory of Schrodinger's equation and the second corrected version was exactly Schrodinger's wave equation as written in the papers he had sent Einstein. Luckily Einstein wrote to Schrodinegr first or we would have another plagiarism scandal on our hands. In my own experience I was very disappointed when I was finshing my thesis to see that one of "my ideas" had been published when the proceedings appeared of a conference I had not attended appeared. Grrrrr. I later discovered that exactly this idea was in a paper of about 8 years before (where it was a minor idea, not the main thrust of that paper). I know I had read that earlier paper, and I know the other guy had read that earlier paper as well. So both of us had reproduced it without knowing (and I think the other guy is still convinced he never saw it anywhere else first). I kknow of similar things that I am convinced I told garduate students and they are equally convinced I never told them. :) E4mmacro 18:02, 2 March 2006 (UTC)

[edit] You will be assimilated - and a thought experiment

I copy and paste from above:

[...] discussions at conferences. Neither side is really listening to the other (just waiting to say their bit), but each is capable of reproducing later what the other said and being completely convinced they were never told of it. [...]

Hi Michael,

you portray yourself like the Borg from Star Trek: assimilating everything and never looking back. :-)

As far as I have been able to tell, none of Ives's publications are available via the internet. It is my understanding that Herbert Ives was a firm anti-relativist, so it is ironical that Ives' legacy in physics - the Ives-Stilwell experiment - is routinely presented as a confirmation of relativistic physics. (The current Ives-Stilwell experiment article is just a stub, and possibly not historically correct.)

I don't know whether Ives used some neo-Lorentzian interpretation of the Lorentz-transformations, or that he had a theory of his own.
It is on the wikipedia talk pages that I have learned for the first time that there are a lot of people who do accept that the Lorentz transformations are applicable, but who are not buying the Einstein approach. There seem to be oodles of neo-lorentzian interpretations around.

In the mainstream scientific community the Einstein approach is firmly established. I don't recall encountering a description of an experiment that was designed to distinguish between neo-lorentzian interpretation and Einstein interpretation.

Personally, I can only think of a thought experiment.
Cavendish measured the gravitational constant by measuring the gravitational attraction exerted by a lead sphere with a weight of 350 pounds. Description of the Cavendish gravitational constant measurement

We have good reasons to assume that active gravitational mass is always equivalent to passive gravitational mass, and that gravitational mass is always equivalent to inertial mass. No experimental evidence is known of a case of gravitational mass not being equivalent to inertial mass.

Suppose we assume that there is a Lorentzian ether. An Lorentz-type ether theory requires that inertial mass increases with increasing velocity with respect to the Lorentzian ether. Then it follows that a Cavendish gravitational constant experiment, onboard a spacecraft free-floating in space, will measure a different value, depending on the velocity of the spacecraft with respect to the Lorentzian ether.

On the other hand: according to the Einstein approach, in which velocity with respect to the structure of space and time does not enter the theory, we have that whenever the spacecraft is moving inertially (regardless of what it did before that; we assume motion to be memoryless), always the same gravitational constant will be measured.

I'd like your opinion on that thought experiment. Do you think it is an interesting thought experiment, in the sense that it probes what you logically expect from the theory of relativity. --Cleonis | Talk 19:44, 2 March 2006 (UTC)

That is a very interesting thought!
  1. I wish Poincare had described his theory of gravity (or I knew more about it). i.e, gravity modified in the light of Lorentz 1904, perhaps the same as theory he attributes to Lorentz, which Minkowski also did some work on, I think. Did he assume that Gravitational mass changes the same way as inertial mass. My guess is that he did.
  2. Likewise I guess Lorentz (who as at heart an aether theorist) would make the same assumption. That is I think aether-theorists would say this is a natural assumption (depending which way the experiment goes!). In fact aether theorists would probably assume there is only one mass - the discussions about inertial mass/gravitational mass which I think I first heard when I was 20 years old seemed very strange to me. On the other hand, Poincare and Planck do indicate that they consider the increase in inertia as an electromagnetic effect and not a "real mass", so it is a very interesting experiment, particularly if there were any difference!
  3. Do we need a space ship? Why can't Cavendish's experiment be repeated at different times of the year, and time of day, i.e, different speeds rel to the aether? If two masses are hanging, and the force of gravity varies between them, wouldn't the angle of the suspension wire change? Oh the earth's gravitational mass changes as well, so ... How to measure the force some way in which v^2/c^2 effects could be detected? Torsion of the wire? I worry that Lorentz contractions ruin all these detection devices?
  4. I don't know of an aether theory of gravity except Ives's un-developed one (in his collected papers there are letters and manuscripts). He does publish a few papers on "An interferometer in a gravitational field" and applies the principle of relativity to get some standard results of GR. In the unpublished stuff he imagines the aether flowing into the mass (like a sink in a perfect fluid, don't ask where it does to). A stationary mass near that mass is then has aether flowing through it and tehrefore mass increase, and time dilation apply at that point. In free-fall they don't apply (falling same as the aether).

E4mmacro 20:22, 2 March 2006 (UTC)

Cleonis. Can you put yourself in another space ship, watching the Cavendish experiment being done on earth, moving approximately in a straight line relative to you. You see the wire twist, you see Lorentz contractions, you have different simultaneity. Now I know it is easier for you to transform yourself into the Earth frame and consider it all from that frame but if you had to give a description of it from your spaceship frame what would it look like? Do the Lorentz constractions of the wire or any of the measuring devices lead to apparent paradoxes that have to be resolved using the simultaneity explanations. I am thinking of things like the Touton-Noble experiment: it appeared from Maxwell's theory that a couple should exist on a charged capacitor moving through the aether. This tiny couple (or moment) should vary from day to day, season to season. Lorentz showed to first then second order that contractions due to motion introduced a coupe, exactly cancelling the first couple. Hence the capacitor had no couple acting on it. If you can produce the spaceship-based explanation then I think you have produced an aether-theory explanation (since there is one possible spacehip at rest in the aether). This is why the two theories are equivalent in all respects except philosophical ones, as far as I can see. E4mmacro 20:39, 2 March 2006 (UTC)
Wouldn't "instanteous collapse of the wave packet" (i.e quantum mechanics, which I don;t claim to fully understand at all) be a source of possible detection of an absolute frame - simultaneity in that frame has a meaning in that thsi "collapse" is instanteous in that frame. I could be talking rubbish here of course. E4mmacro 20:44, 2 March 2006 (UTC)


Wow! My thought experiment has gotten you all fired up, it seems. :-)
In the case of the Trouton-Noble experiment, all the interactions involved are electromagnetic interactions. So once a theoretician has granted that in the physics of electromagnetism the Lorentz transformations apply, things can be taken from there.
Now, of course, Lorentz had to assume that a planet that is moving through the lorentzian ether is flattened in the direction of motion, just as everything else. That is a modification of how the force of gravity is transmitted.

[edit] Coulomb force couples to electric charge, what does gravity couple to?

But does the force of gravity couple to the rest mass, or to the total mass? If gravity couples only to the rest mass then the ether theory stands a chance of reproducing the prediction of the Einstein interpretation, as the rest mass is invariant under Lorentz transformation. But as far as we know gravitation involves the total mass. This is an illustration of the fact that in relativistic physics gravitation just bursts out of the confines of special relativity. Something has to give.
This theme is similar, I think, to the theme in John Nortons paper about Nordström's Lorentz invariant scalar theory of gravitation; gravitation just bursts out of special relativity, and a successor to special relativity is needed. (And was provided by Einstein.)

Poincaré's 1905 Palermo paper (facsimile reproduction, non-digital, 3 MB file) has a considerable section about gravitation. I'm not sure, but I don't think that Poincaré demands gravitational-inertial mass equivalence as a constraint on the theory. I think that if Poincaré had anticipated that light is deflected by gravitation, he would have written so.
I think it was well after 1905 that recognition came that light does not only carry momentum, it also carries inertial mass. When light propagates from an emitter to a receiver, it not only transmits momentum, it also transmits inertial mass. The inertial mass of the emitter decreases on emission of the light, and the inertial mass of the receiver increases on absorption. Of course, light has zero rest mass. Since light has zero rest mass, the natural assumption is that light is not affected by gravity.
Possibly, considerations of this nature made Poincaré very, very cautious towards attributing inertial mass to energy.

In his 1909 Göttingen lecture, Poincaré went very far in attributing the increased inertia of a fast-moving electron to increased energy of the ether surrounding the electron, in response to the high velocity of the electrons. Can that still work for muons and tauon's? My understanding is that electrons and muons are identical as far as electric charge and spin are concerned, but that they are different in rest mass. Should electrons and muons become more and more alike at higher velocities? To my knowledge: at all velocities the energy of muons is the muon's rest mass multiplied with the relativistic factor.

I am indeed very curious how Lorentz dealt with these issues. As you indicate: historians of science describe that Lorentz retained a preference for using a lorentzian interpretation, but from the lectures Lorentz gave in the 1920ties it can be seen that Lorentz had full mathematical mastery of special and general relativity. --Cleonis | Talk 21:44, 2 March 2006 (UTC)

[edit] Measuring the gravitational attraction between two spheres

I copy and paste from above:

:I am thinking of things like the Trouton-Noble experiment: it appeared from Maxwell's theory that a couple should exist on a charged capacitor moving through the aether. E4mmacro 20:39, 2 March 2006 (UTC)

In the relativistic Cavendish experiment that I proposed there is no restriction on how the gravitational force between the masses is measured. Cavendish happened to use a torsion balance, obviously that is not the only way.

Examples:
Let two spherical masses be floating in a hold inside the spacecraft, centimeters apart. Due to their gravitational attraction the two balls will move towards each other. Instruments can measure how hard each ball accerates with respect to the hull of the spacecraft.
Another possibility is that a low pressure air cushion is supplied in the gap between the two balls, so that the gravitational attraction cannot pull them closer. The low pressure air cushion would have to be provided by using a tiny, low mass tube, supplying a minute flow of air right between the two masses. The magnitude of the air flow that counterbalances exactly the gravitational attraction between the two masses is then a measure of the gravitational constant. --Cleonis | Talk 22:30, 2 March 2006 (UTC)

I was also thinking that to measure the accleration to the required accuracy you would need an interferometer which would probably then bring in complications. Pressue is interesting and Planck's 1907 that enthalpy (not just energy) has a mass equivalent may now come into play. Do you know of relativistic thermodynamics? I haven't thought about it much, except that the Maxwell-Boltzmann thermal speed or velocity distribution would have to be altered somehow, and therefore pressure woudl alter with velocity in some sort of Lorentzian way. I always assumed this has been done, but just don't know the references. E4mmacro 22:54, 2 March 2006 (UTC)
I think relativistic thermodynamics would deal with the velocities of the atoms/molecules relative to the common center of mass, in other words relative to each other. The velocity of the common center of mass with respect to the structure of space and time does not enter relativistic thermodynamics (since velocity with respect to the structure of space and time never enters relavistic theory)
The more difficult and messy (I assume) description of the molecule's motion wrt to a frame in which the centre of mass of the molecules is moving seems a normal thing to ask. We do this, or the equivalent, all the time in fluid mechanics (put ourselves in the frame of reference of the body moving through the gas) - I assume there is a relativistic fluid mechancis as well. E4mmacro 23:52, 2 March 2006 (UTC)
I was refering also to the fact that, even in the rest frame of the molecules, the thermal speed (or velocity distribution) extends to infinity. According to Maxwell-Boltzmann, there is a non-zero chance that a molecule in a gas in equilibrium at temperature T may have a speed great than c. There must be a derivation of the Boltzmann distribution that considers relativistic energy and give a different answer from the classical one. (i.e relativistic statistical mechanics).
Special relativity assumes that motion is memoryless. So everytime there is a phase of inertial motion, then no matter what acceleration has gone before that, during inertial motion thermodynamics is the same as during any inertial motion.
I suppose that if one insists on a Lorentzian interpretation, then one does need to redevelop thermodynamics from scratch. --Cleonis | Talk 23:30, 2 March 2006 (UTC)
Well that would be something you need, I think, to show a difference between an aether theory and SR. If classical physics hold then clearly the pressure device is independent of motion. It is not clear that this holds if there are effects of motion thru the aether (and the principle of relativity is some sort of accident or outcome of lots of compensating effects which conspire to make motion undetectable, whhich seems to be the basis of the aether theories).

[edit] Re Folsing

Hi Michael, I've replied on my talk page with some answers to your questions. Paul August ☎ 18:14, 10 March 2006 (UTC)

[edit] Einstein /Poincare source

Heya. You wrote in reply to the Licorne affair that "Whittaker did not mention that Poincare did not believe this result and advanced it as a criticism of Lorentz's theory. He did not mention that Poincare called it a "fictitious" density and that Poincare had no idea where the mass came from; it was just created and if it was real mass this creation would violate the conservation of mass principle. Nor did Whittaker mention that Poincare retained this view until 1904 at least, since he discussed this problem a number of times in his popular science books from 1902-1904." I'm doing a report on this stuff for school, I was just wondering if you have a source on these claims? I'd really appreciate it! Lucidish 21:35, 3 April 2006 (UTC)

Just my own reading of Whittaker (1953) and Poincare (1900,1902,1904). It is clear that Whittaker (1953) doesn't mention those things about Poincare I listed. For the claims about Poincare's understanding of what he was doing in the 1900 paper I have only my own reading of the paper (the introduction starts with an apology for criticising Lorentz's theory, since it was published in a Lorentz tribute edition of the journal) and Poincare's books where he dicusses the recoil a number of times. I gave a few quotes frrom Poincare 1900 in a few places on the talk pages (Poincare talk I think), plus what I think is a decisive quote from Poincare 1904 (this was in reply to a question by De Kludde) to support my claim that Poincare did not understand e=mc^2 in the way Einstein did. I will look for the quote, probably on the dispute talk page. E4mmacro 04:09, 4 April 2006 (UTC)

Nice, that'd be shiny. Whereabouts did you get your hands on the copy of Archives Neerland? My university library, sadly, has none of it; the only available online source I could find appears to be defunct; and I feel iffy about citing Wikipedia. Lucidish 04:16, 4 April 2006 (UTC)

One quote from The Value of Science 1904: "the apparatus recoils ... and that is contrary to the principle of Newton since our projectile here has no mass, it is not matter, it is energy". E4mmacro 19:11, 2 March 2006 (UTC)

I have a copy which I think the Britsih Library found for me in about 1982. I have a pdf copy of it (not great quality), and intend some day to perhaps publish a translation with commentary. I had got a certain way with this before semester started, and came across a confusing bit about Poincare's understanding of Lorentz's local time, (it appeared to me that Poincare mis-applied it, but I was reluctant to believe this and haven't had time to re-consider it). E4mmacro 04:23, 4 April 2006 (UTC)

I see De kludde said this paper was on page 468 of Poincare's Collected Works vol IX. I see my library has Poincare "Ouevres" in many volumes, so perhaps it is here as well. E4mmacro 04:32, 4 April 2006 (UTC)

Thanks for the references, I'll look into them. (My library does have Ouevres, and Value of Science).
But I confess, I'm a non-physicist. Could you explain the significance of the Value of Science quote? If I understand correctly, it's an indication that he still thought that mass and energy were mutually exclusive - that energy has no mass. Is that right?
Also, I'd really appreciate any quote that supported the idea he'd called it a "fictitious" density. Is that also in Value of Science? Lucidish 16:09, 4 April 2006 (UTC)

Looking through the Value of Science now. According to my edition, it was published in 1913, and the quote you mentioned was done purely as a way of framing the consequences of Newtonian physics, not an expression of his own views. Indeed, this is preceded by a section on the principle of relativity which is pretty glowing (or so it seems from a quick read), because he says that it makes good sense from the experimenter's point of view.

Still, he does confess that he had sworn that Newton would be upheld in the face of relativity, and that his predictions were being shot down by current studies; but I'm not sure that that particular quote you gave is a smoking gun (or oscillator, hyuk hyuk). Though, if it was written in 1913, none of this is surprising, it being a decade after Einstein's breakthrough.

I looked at your translation and the french pdf and have some translation worries. He talks about energy as if it were "a fictitious fluid", not directly saying that its density is fictitious. But I don't know how to translate this in order to get his intent. The reading I come away with is that he's saying, "Ok, let's think of energy as a fluid, just for the sake of argument." In that case, though we might infer that he was saying energy has no mass, and that's why he introduced the fluid analogy, he would not (it seems at first blush) be directly saying that the density is fictitious. Or maybe I'm being overly pedantic, but that's how it came off to me.

None of this is to deny that Poincare still hugged tight to various quaint notions that Einstein would later subdue, since Poincare does talk about his own reluctance to let go of Newton in Value of Science. I just wanted to remark about my readings of your sources. I was hoping for really knock-down stuff, but oh well. Anyway, you've given me interesting things to ponder in the essay, at least; thanks again for your help! Lucidish 05:13, 6 April 2006 (UTC)


My purpose was just to counter the claim by Whittaker and Licorne and others that Poincare discovered e=mc^2 in its modern meaning. I think the idea that radiation possessed inertia was fairly well accepted ever since Maxwell's radiation pressure was known. Fairly sure Value of Science was published 1904, Republished as Foundations of Science: a collection of three books (Scince and Hypothesis, Value of Science, Science and Method in 1914, possibly the first english translation. E4mmacro 00:10, 7 April 2006 (UTC)

My edition says: "This edition is comprised of three separate volumes by Henri Poincare: Science and Method (1905), The Value of Science (1913), and Science and Method (1914)." But yeah, you're probably right that those were the publication dates of the translations.
Oh, and I've been meaning to ask, which page of the Neerland paper is Whittaker sourcing? Lucidish 01:51, 7 April 2006 (UTC)
Sorry for all my confusions. But, in comparing the versions, in what I think Whittaker had in mind when making his reference, I find the original french version reads something like: "We can regard the energy as a fictitious fluid having a density J^0c^2". But your computer copy and translation says "J/c^2". Are they equivalent? Lucidish 20:36, 7 April 2006 (UTC)


The original says "la densite est K_0 J". In Poincare's notation K_0 = 1/c^2. J is the energy density. You can see at the bottom of p272, "Si alors V = 1/sqrt{K_0} est la vitesse de la luminere ( i.e. c=1/\sqrt{K_0} in modern notation). E4mmacro 03:57, 10 April 2006 (UTC)

Salve E4mmacro, the following book may be of interest in this context: Anatoly A. Logunov, Hentri Poincaré and Relativity Theory (transl. from Russian by G. Pontecorvo and V. A. Soloview), Nauka, Moscow 2005 [1]. Did you already know it? See also [[2]]. Concerning your recent comment, I was not referring to Lorentz's electron theory but to the Lorentz transformation which, in my opinion, is misinterpreted today. KraMuc 14. July 2006

[edit] relativity of simultaneity article

How are you doing? To my astonishment, EMS stubbed the [Relativity of simultaneity article], without prior discussion let alone consensus. IMO there is some text that is hardly relevant, but much less than he deleted and it should be discussed. Thus I reverted, and I also searched for a possible cause; the explanation can be found on User talk:Ems57fcva. Thus, be prepared! I will welcome improvement of that article, but not deletion. Cheers, Harald88 22:39, 30 August 2006 (UTC) PS. See also his comments on my Talk page. Harald88 06:52, 31 August 2006 (UTC)

Hi. I don't dislike the history; I just think that the article needs to be primarily a scientific article, rather than an historical one. Also, if there is an organizational principle to the writing at the moment, it seems to be historical rather than pedagogical. I, for one, hope that you keep an eye on things and maintain a well-referenced historical section towards the end of the article. (I'm guessing there will be lots of edits coming soon.) I think that would be helpful, and you are well positioned to do it. MOBle 05:55, 8 September 2006 (UTC)

[edit] rely mostly on secondary sources?!

Hi I know how you value the verification of information from the original sources. Thus I think it may be useful if you comment on a disagreement on WP:NOR where some editors push for inclusion of the following statement:

"Articles which draw predominantly on primary sources are generally discouraged, in favor of articles based predominantly on secondary sources."

Apparently I have difficulty explaining them such an additional rule is not required by policy nor beneficial for the quality of an encyclopedia.

Perhaps you can help out?

Cheers, Harald88 15:13, 21 September 2006 (UTC)

[edit] RPD user

I suspect that we're dealing with Christopher Jon Bjerknes himself this time. Looking at the CJB page log, you can see some of his edits done without being logged in, and this address, 24.15.188.92, is an IP in the Chicago area that was also active on Einstein a few years ago. His (fictional?) "XTX Inc." is claimed to be in Downers Grove, Illinois. The sense of his own importance would fit. --Alvestrand 02:50, 16 July 2007 (UTC)

I think we need to de-hype his stuff. Just change to "what's documentable", not "it's obvious". But if it's indeed CJB, then I think we can safely assume that he won't give up easily, if at all. --Alvestrand 11:18, 16 July 2007 (UTC)
Thought you'd find this edit amusing: [3]. RPD removing, vituperatively, text that he himself added earlier. --Alvestrand 13:39, 17 July 2007 (UTC)

[edit] License tagging for Image:Overlaid1.jpg

Thanks for uploading Image:Overlaid1.jpg. Wikipedia gets thousands of images uploaded every day, and in order to verify that the images can be legally used on Wikipedia, the source and copyright status must be indicated. Images need to have an image tag applied to the image description page indicating the copyright status of the image. This uniform and easy-to-understand method of indicating the license status allows potential re-users of the images to know what they are allowed to do with the images.

For more information on using images, see the following pages:

This is an automated notice by OrphanBot. If you need help on selecting a tag to use, or in adding the tag to the image description, feel free to post a message at Wikipedia:Media copyright questions. 07:07, 20 October 2007 (UTC)

[edit] History of Lorentz transformations

If you are interested in: In the last weeks I've expanded the article History of Lorentz transformations, which you started in 2006. --D.H (talk) 09:34, 13 February 2008 (UTC)