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Question about Special Relativity

  1. Feb 15, 2004 #1
    Was not the Special Theory of Relativity and the Lorentz Transformation created simply to explain why the Michelson-Morely experiment did not detect any change in light caused by the ether?
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  3. Feb 15, 2004 #2

    Chi Meson

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    It was an Irish physicisist (what was his name?) who first suggested that the null result of the M-M experiment might be due to a compression of the apparatus along the direction of motion of the ether. THis idea was part of the reluctance to let go of the notion ofth ether which physics had devoted so much time and theory to. Lorentz then came up with his contraction formula. SO it was, initially, used for length contraction as caused by the ether.

    Special relativity was produced by Einstein due to completely separate initial assumptions (the postulates) which require there to be no absolute reference frame, and therefore no ether. IT just so happened that SR required there to be length contraction along the direction of relative motion, and the formula for this contraction was exactly the same as the one developed by Lorentz.
  4. Feb 15, 2004 #3


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    So to be more concise: yes.
  5. Feb 16, 2004 #4

    Doc Al

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    George Francis FitzGerald (1851-1901).
  6. Feb 16, 2004 #5


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    I feel that this is a massive understatement of the problem Einstein addressed. The issue at stake, the reason the M-M experiment was done, was due to Maxwell's prediction. When Maxwell predicted that the speed of electro-Magnetic waves was independent of any other velocities, he threw the tried and true Galilean transforms out the window. This created a schism between Electromagnetism and classical mechanics which disrupted the world of physics for 50yrs. Einsteins derivation tied it all back together. The beauty of it was the simplicity of the derivation, the result was the already known Lorentz transforms, the method gave them a simple clear physical meaning.
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