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Michelson–Morley experiment

  1. Jul 30, 2009 #1
    I have read through the experiment but how does the , Michelson–Morley experiment
    show that space is a vacuum can someone explain this to me.
  2. jcsd
  3. Jul 30, 2009 #2

    Vanadium 50

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    Um...it doesn't. It shows the speed of light is independent of the motion of the earth around the sun.
  4. Jul 30, 2009 #3
    It doesn't show that space is a vacuum. It shows that light does not propogate through anything (previously they thought light was a wave that propogated through a medium they called the lumineferous ether, like a water wave travels through water). If light travelled through a medium then its speed would depend on how one was moving relative to this medium (just like if one is in a boat cruising along with the waves at the same speed, relative to you the waves aren't moving at all). However, the found that no matter which direction the checked the speed of light they got the same answer. This would be impossible if light travelled through the medium because the earth is moving in a certain direction and so if there was a medium light would move slower in that direction just like the boat cruising along with the waves. However, the speed of light was identical no matter which way they oriented their apparatus.
  5. Jul 30, 2009 #4
    i see , thanks for the answer
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