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Do planck frequency photons form near black holes?

  1. Jun 22, 2011 #1
    Locally, photons "blue-shift" when falling down a gravitational field. What happens when they arrive at the Planck frequency? Do they turn back into matter?
  2. jcsd
  3. Jun 22, 2011 #2
    Long before then they'll arrive at the electron-positron annihilation energy and probably turn into matter.
  4. Jun 23, 2011 #3


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    This is actually a hairy question. I was tempted to say nothing can happen, since to some observer moving very swift towards the photon will always see them blue shifted beyond the planck fequency.

    The answer (or lack thereof) comes about since special relativity does not take quantum effects into consideration at all -- only the speed of light.

    I dug up this old post by Marcus which should elucidate matters: https://www.physicsforums.com/showpost.php?p=348986&postcount=12
  5. Jun 24, 2011 #4
    Limitation of special relativity is near speed or at speed of light particle. special relativity assume no particle can get speed of light or not valid to light particles. Don't apply all theory as mix and match, they all got limitations. you can't fly a car as a rocket and vice versa, limitations is break to your mix match imagination.
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