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Photon speed

  1. Apr 9, 2006 #1
    How can a photons velocity be slowed down when they pass through air, water, etc? If photons can be slowed down to slower than light speed, then would it not be possible for a "futuristic lightspeed rocket" to catch up to a photon? And also how can someone measure a slower speed (other than the speed of light) for a photon if special relativity states that all observers must measure the exact same speed of light? What am I missing?
  2. jcsd
  3. Apr 9, 2006 #2


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    Staff: Mentor

    See the following posting in the Physics Forums FAQ:

    https://www.physicsforums.com/showthread.php?p=899393#post899393 [Broken]
    Last edited by a moderator: May 2, 2017
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