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Gravity and force from black hole

  1. May 8, 2015 #1
    this seems like a dumb question but i just cant think of a solution. black holes can suck photons, that's why they are black. but there are charged black holes, and the EM forces is mediated by photons, so how can the mediating photon escape the gravity? also arent the gravitons (i know gravitons is unconfirmed...) themselves subject to the same thing? so in other words black holes should just be a dot in space with no force around it.
     
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  3. May 8, 2015 #2

    PeterDonis

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  4. May 8, 2015 #3

    bcrowell

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    An explanation I've seen is that the Coulomb force is transmitted by virtual photons, which don't have to travel at c. I'm not strong enough at field theory to know whether this is really a rigorous explanation.
     
  5. May 8, 2015 #4

    PeterDonis

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    The Usenet article mentions this, but it links to other articles which discuss the limitations of this view. Also, as the article notes, virtual photons are a quantum concept, and it should be possible to have a classical explanation of what's going on (which the article provides).
     
  6. May 8, 2015 #5

    bcrowell

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    The OP's question was explicitly quantum-mechanical.

    I don't see why there would be any mystery classically.
     
  7. May 8, 2015 #6

    PeterDonis

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    In the sense that the term "photon" was used, yes, it is on its face. But that term gets used a lot to mean something that is much more accurately described as either a classical EM field or a classical "pulse of EM radiation". Also, physically speaking, unless the black hole is of very small mass, a classical description should be sufficient.

    I don't think there is either, but I'm not sure the OP realized that there isn't.
     
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