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I Graviton scattering

  1. Feb 9, 2017 #1
    Is it possible to compute scattering amplitudes of a graviton interaction taking Einstein gravity as an effective field theory at low energies?
    I did not study qft the proper way yet, so any clarifications on the subject would be welcome.
  2. jcsd
  3. Feb 10, 2017 #2
    I don't know much about scattering, but quantum gravity (and gravitons) does not seem to cooperate with GR. So probably not.
  4. Feb 12, 2017 #3
    So far my limited knowledge on the topic, until now, we were only able to detect gravitational waves (and this was not an easy task) but unable to isolate a graviton. The graviton is a undetected predicted particle.
  5. Feb 12, 2017 #4
    Yes, this should be possible. We would refer to it as refraction of the gravitational waves, just as we do with light whenever individual photons are not relevant. To translate to "graviton density", simply divide the energy flow of the waves by ωħc.
    A low-energy condition is necessary not so much because of quantum effects, but because at higher energies the nonlinearity of GR itself makes the wave description fall apart.
  6. Feb 12, 2017 #5


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    The answer is yes, quantum gravity is well approximated at long distances by an effective field theory of gravitation. A particular diagram or class of diagrams (like graviton scattering) are readily computable and are often homework problems given to grad students in this field.

    See some of the famous review articles by Donaghue or Burgess:
    like eg:
  7. Feb 12, 2017 #6
    Thank you!
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