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I Black hole - event horizon and Hawking radiation

  1. Jul 1, 2017 #1
    I have come across the following multi-explanations of how Hawking radiation/evaporation of a black hole happens:

    Particle/anti-particle story:

    particle/antiparticle pair creation from vacuum near the event get torn apart - one going into black hole, the other away; in some of these explanations the anti-particle always goes in and energy/mass is lost, radiated away by the particle that got away, the particle going in is somehow negative - not very clear to me; other twist is that this separation causes them to be real particles, not virtual particles any more; radiation/evaporation flow from this in some way - explanations of why the

    Entanglement story
    there is no particle/antiparticle pair creation - it's just two virtual particles created out of the vacuum and joined by entanglement, again one goes in and one goes away m- not sure what happens to their entanglement; again for some some reason I can't quite grasp the one going in doesn't add but subtracts mass/energy and the one going away also takes some energy/mass away; again there is talk about the particles become real during the process

    Some combination/permutation/refinement of the above two story

    Math story is only real story
    Neither of the stories above are anything but some type of analogy - nothing of the sort happens; it's complicated math at the event horizon and for some reason people have come up with the above not-so-simple actually elaborate scenarios for people who don't have the mathematics so they can understand analogies which aren't real.

    So reality - math - is more like this: http://math.ucr.edu/home/baez/physics/Relativity/BlackHoles/hawking.html


    if anybody could illuminate which is the closest answer it would be appreciated.

    Are the analogy-style answers not even possible? In other words pair-production taking place just outside of the event horizon doesn't play any role at all? It happens but so what as far as radiation/evaporation of black holes - "so what " meaning nothing at all as opposed to a very very very tiny effect.

    Thanks for any feedback in advance.
     
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  3. Jul 1, 2017 #2

    phinds

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    Correct. The "people" who came up with it was Stephen Hawking himself. He said the virtual particle pair thing was the only hueristic he could find that even began to express in English what really can only be expressed in the math.
     
  4. Jul 1, 2017 #3

    PeterDonis

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    Where? Please give specific references.

    The Baez article you link to is probably the best that can be done at the lay person's level.
     
  5. Jul 2, 2017 #4
    Thanks for the response. As far as my question -

    "Are the analogy-style answers not even possible? In other words pair-production taking place just outside of the event horizon doesn't play any role at all? It happens but so what as far as radiation/evaporation of black holes - "so what " meaning nothing at all as opposed to a very very very tiny effect."

    Heuristic or not is the pair-production story completely fake news? It sounds plausible and possible - maybe it's not the whole story or a big story or an important story for the purposes of Hawking radiation but is it no story at all? It just can't happen - there is no way a pair of virtual particles are created near the horizon and one goes into the black hole and the other goes out and 'never' the twain shall meet again? I did see a rather long explanation of how this could physically happen with just the right trajectory for the one that gets away, had to be a certain wavelength involved - they were dealing with photons. And it was either Leonard Susskind or someone of his level. If this scenario is completely heuristic they sure put a lot of time into making it seem like it wasn't just a way of explaining things to people who don't have the math.
     
  6. Jul 2, 2017 #5
    It seems like the analogy Hawking provided is the best us laymen will get considering the math involved here:

     
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