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Mass, speed

  1. Oct 24, 2011 #1
    do all mass less particles travel at the speed of light?
  2. jcsd
  3. Oct 24, 2011 #2

    Doc Al

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    Staff: Mentor

  4. Oct 24, 2011 #3
  5. Oct 24, 2011 #4
    PHRAK.....Stop teasing Doc Al!!

    Best answer I know: that's what we observe.
  6. Oct 26, 2011 #5
    But I was just getting started...

    First we have "particles" and they're "moving", and this is supposed to be physics 200 years after Newton.
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