Talk:Special relativity

Pythagorean theorem

This is a nice article! Since you mention the Pythagorean theorem in the example of the light beam in the train, why not complete the thought and note that the formula for time dilation follows directly from it? The Lorentz transformations don't actually involve any advanced mathematics. Greg Woodhouse 22:41, 25 June 2007 (CDT)

I'm trying to keep the article pitched as non-technically as possible, since--amazingly--relativity's basic effects are much more accessible than people would have thought in 1905. If you mean to derive Lorentz from Pythagoras, I think that would make a lot of people's heads spin. If you mean just mention the connection in the article, then I think you should work it in if you see a good way to fit it. My only concern about the Lorentz Transformation is that it's kind of its own deal, and paying too much attention to it here might only distract. It's interesting you brought this up, though. I labored over whether to say more about Lorentz, but I came to believe that even though it apparently doesn't require more than high school algebra, the idea of transformation, of mapping one coordinate system onto another is not a high school notion, especially with time involved. I think even the Galilean Transformation would actually cause people more difficulty to fully comprehend than anything else in the article. Thanks for catching my latex typos, by the way. Nathaniel Dektor 22:53, 25 June 2007 (CDT)

Applications

The article seems to suggest that relativity is of no practical significance. This may be true in the macroscopic world (unless we want to rely on an atomic clock on fast moving spaceship!), but it is certainly not true of subatomic particles. For example, if muons decay in 2.2 microseconds, how is it possible that we're able to detect muons from outer space? (Answer: if they are moving at speeds approaching c, then they will take a very long time to decay by our reckoning, or, if you like, will travel very far before decaying). Greg Woodhouse 23:52, 25 June 2007 (CDT)

Myself, I've never detected a muon. It becomes a different story when you introduce tools of detection. But this kind of impingement of relativity on real working people (physicists) sounds like a good fit for the article because it's accessible to a more general kind of interest. My only intention in the article was to show how relativistic effects are well beyond humans' senses, counterintuitive, and kind of weird. If you think about it would be weirder if light's speed was infinite even though we experience it that way. Nathaniel Dektor 00:14, 26 June 2007 (CDT)

Well, how about a brief calculation? The diameter of the earth is about 12,750 km and the speed of light is about 3 x 10^9 m/sec, so if my math is right, a light beam could pass through the earth in about .00425 seconds, or about 4 thousandths of a second. Anyway, I'm just thinking out loud here. Greg Woodhouse 00:32, 26 June 2007 (CDT)

Less quality than Wikipedia...

A comment here was deleted by The Constabulary on grounds of making complaints about fellow Citizens. If you have a complaint about the behavior of another Citizen, e-mail constables@citizendium.org. It is contrary to Citizendium policy to air your complaints on the wiki. See also CZ:Professionalism.

[Note: The deleted sentence expressed criticism about an aspect in which the article needs to be improved: some narratives that have been removed from Wikipedia because of their known inaccuracy have reappeared in Citizendium articles, which is certainly regretful. My phrasing could have been better, but no complaint was made about a fellow citizen - sorry if someone took it personal!] Harald van Lintel 13:00, 29 November 2007 (CST)

For example, the Michelson-Morly experiment only did not detect motion relative to the hypothetical ether and Einstein did not "refuse to assume the possibility of an ether" (more strikingly, he later he even positively assumed its existence based on its perceived properties); also, most historians of science (such as Darrigol) nowadays acknowledge that special relativity was the work of Lorentz, Poincaré and Einstein - which makes it a bit blunt to call it "Einstein's theory" etc. (compare the article on Quantum mechanics - not "Planck's Quantum Mechanics"). Interestingly, Poincaré called it Lorentz's theory, Lorentz called Einstein's interpretation of it Einstein's theory, while Einstein recognized it as the theory of him and Lorentz, and at times Lorentz (and once Einstein) recognized the contributions of Poincaré.

There is more, such as the single-sided Point of View that the Twin paradox "is not a pararadox", eventhough Einstein called it a paradox himself - it is a paradox according to the dictionary definition of "paradox" (I studied paradoxes and wrote an article about an SRT paradox).

So, the above was in part in order to vent a little my annoyance, but of course I intend to constructively help in improving this and other articles. :-)

...said Harald van lintel (talk) (Please sign your talk page posts by simply adding four tildes, ~~~~.)

In reaction to a comment here that was today removed by the one who placed it (is a full deletion "minor" in Citizendium?):

Thanks, I take note of your explanation that it is not an approved article and has thus undergone no formal scrutiny by a topic specialist. I obviously had unrealistic expectations of articles "in the making" and I'll come back to this article later to help improving it. :-)

Regards, Harald van Lintel 13:00, 29 November 2007 (CST)

scriptstyle is making text hard to read

Could the authors simply use italics or the normal math tags for the equations? The scriptstyle thing is making the interesting equations very small and hard to read:

Current way:

Since $\scriptstyle distance=rate\times time$ we now have

$\scriptstyle d=ct$

and

$\scriptstyle D=ct^{\prime }$

Better way

Since $distance=rate\times time$ we now have

$d=ct$

and

$D=ct^{\prime }$

Sorry, I forgot to sign the above. David E. Volk 16:48, 6 March 2008 (CST)

How did Lorentz get there?

In various places (Meaning of Relativity, 1922; Relativity: The special and general theory (1916); On the electrodynamics of moving bodies (1905)) Eisntein made it clear his work was derived from Lorentz. I was wondering, what with all the grey matter we have assembled here, if anyone could explain how Lorentz got this:

${\sqrt {1-{\frac {v^{2}}{c^{2}}}}}$

An explanation for the average reader--to whom Einstein addressed much of his work by the way--would be very helpful. Thomas Simmons 20:48, 27 December 2008 (UTC)