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Planck Stars

  1. Jan 28, 2014 #1

    This looks very interesting, they are claiming a potential test for quantum gravity . What do we think?
  2. jcsd
  3. Jan 28, 2014 #2


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    We think Marcus has already started a thread about this.
  4. Jan 28, 2014 #3
    Thanks, I didnt notice that, it was in the beyond the standard model section, but it appears no one has said anything interesting there either, so the questions remains.
  5. Jan 30, 2014 #4


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    Cosmic ray implications of Planck stars.

    I agree. The Planck star idea is extremely interesting both from the quantum gravity angle and from the ASTRO/COSMO perspective.

    There deserve to be TWO threads, one from the QG theory side, and one from the OBSERVATIONAL astrophysics side.

    Assuming Rovelli and Vidotto's analysis is right, and is confirmed by further work, then LQG predicts that at the center of a stellar collapse there is a SLOW-MOTION BOUNCE.

    This bounce happens quickly, almost instantaneously, for an observer on hand near the center of collapse. But because of time-dilation it would appear to a distant observer to take a very long time, possibly hundreds of billions of years depending on the initial mass.

    According to LQG, then, this slo-mo bounce is what is really at the center of a BH event horizon, instead of a "singularity".

    When the slo-mo bounce finally expands out to coincide with the BHEH then it bursts like a bag of very hot gamma-ray photons. It explodes into the observable region outside the BHEH.

    This might be seen, and could contribute a GeV portion of what we detect as cosmic rays. So there is an observational angle to it.

    Skydive, you a were definitely right about the interest of this! After thinking some about it I decided a better home would be Astrophysics Forum because although it does have Cosmology implications too, it is
    1. about the actual structure of black holes
    2. about the radiation, evaporation process, and eventual end of black holes
    3. about the kind of observational footprint we might be able to detect if the model is valid
    So it seemed more about stellar size objects than about the structure of the universe as a whole.
    I started a thread over there:
    Hopefully you and others will join in a discussion over at Astrophysics forum.

    There are also basic BtSM theoretical aspects (understanding Rovelli and Vidotto's model of the process and how based on LQG) so I made a discussion thread over at BtSM for the theory side if people want to discuss it.
    Last edited: Jan 30, 2014
  6. Jan 31, 2014 #5
    Thanks again Marcus, this is really fascinating stuff. Ill come over to that forum, the reasons i think it has comso implication is because if this signal is found then it gives quite a boost to the big bounce idea, dont they use the same modified Freidman equation?
    Anyway see you over at the astro section.
  7. Jan 31, 2014 #6
    Woah!..This is one of the best "WHAT IFs" i had heard in a while. Got me extremely interested. Any related papers are appreciated. Thanks guys!^^
  8. Feb 1, 2014 #7
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