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)