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Einstein/ michelson-morely

  1. Dec 4, 2007 #1
    How does Einstein’s theory of special Relativity explain the result of the Michelson-Morley experiment?

    Thankyou if you can help
  2. jcsd
  3. Dec 4, 2007 #2


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    the Michelson-Morley experiment set out to measure the presence of the hypothetical luminous aether by measuring the difference in the speed of light of two paths of a split beam of light that are at right angles to each other. assuming the Earth must be traveling through the aether at some time during the year as it revolves around the Sun, this difference of speed should be measurable with their apparatus.

    the performed the experiment many times, at different times of day and different seasons of the year and never got a positive result (that is a measurable difference of the speed of light in those two directions).

    Einstein simply said "hell, yes. why not? there was no measured difference in the speed of light because there was no difference in the speed of light to measure." that the speed of light (which is really the speed of any instantaneous interaction, E&M, gravity, strong force, whatever) in a vacuum is constant and the same for any (inertial) observer anywhere in any direction is a postulate of SR. from that postulate Einstein notices that all sorts of strange things happen regarding time, length, apparent mass, especially if one observer is whizzing by another at a speed approaching c.
  4. Dec 4, 2007 #3

    thankyou so much you helped me alot. thank again
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