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Question on the original Michelson-Morley Experiment

  1. Feb 18, 2007 #1
    Maybe this has more to do with the history of physics than physics itself. As you all know, the first Michelson interferometer was constructed in 1881. To my knowledge, the experiment requires a coherent source of light. Just wondering, if the experimental apparatus was constructed before the invention of the laser, then how did Albert Michelson produce coherent light?
  2. jcsd
  3. Feb 18, 2007 #2
    I'm guessing it was collimated through a sequence of slits.
  4. Feb 19, 2007 #3
    as long as both beams of light are emitted by the same force, they can be considered coherent.

    consider a sun ray, if you break up a sun beam into 2 parts, the two parts are going to be approximately (the difference being very small) identical, and as such can be used to construct interference patterns.

    perform a double slit experiment on sunlight to see the effect.
  5. Feb 19, 2007 #4


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    Staff: Mentor

    He used a rotating mirror to create pulses.
  6. Feb 19, 2007 #5


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