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Measured lightspeed in general relativity and moving through space.

  1. Jul 20, 2012 #1
    Hey guys

    I was just wondering the following. Since time slows down when travelling faster, and we move around 1.3 million miles per hour, using the CMBR as a frame of reference. Does this mean our perceived lightspeed is wrong? How fast would we measure time to travel if we managed to come to a complete stop?

    Maybe, if the experiment could be done, this would cause the same problems as reaching speeds close to lightspeed?
  2. jcsd
  3. Jul 20, 2012 #2


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    I think you are misunderstanding the basic ideas. Time slows down relative to some observer. In your own coordinate system (relative to yourself) you are always motionless and time flows at a constant rate. There is no "wrong" or "correct" speed for something. The one thing that is NOT relative to an observer is the speed of light- it is the same no matter what your frame of reference is.
  4. Jul 20, 2012 #3


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    Experiments suggest that the measured speed of light is c, locally, no matter the motions of source and observer.
  5. Jul 21, 2012 #4
    I now see the mistake I've made.

    Thanks guys!
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