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Virtual particles stolen from the universe?

  1. May 23, 2008 #1
    Virtual particles appear and annihilate all over the universe.
    If a pair is created just on a black hole event horizon, the hole can take one particle and the other goes free - the hole has to give some energy in order for this to be real. Hawking, no?

    But - what if two small black holes are approaching eachother at some angle that they will revolve a few times before merging into one, and a virtual particle pair is created so that the particles fly into one hole each? I suppose that means that they radiate into eachother, but hasn't the universe been robbed of two particles?

  2. jcsd
  3. May 23, 2008 #2

    Vanadium 50

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    You can't count virtual particles.

    At the beginning of your problem, you have two black holes and no free particles. Afterwards you have two black holes and no free particles. What's the problem?
  4. May 23, 2008 #3
    Larger mass?

    Two black holes with larger mass than before the virtual particles...
  5. May 23, 2008 #4
    In the virtual pair, one "particle" carries negative energy, and the BH "absorbing it" loses mass.
    The other "real" particle carries positive energy, we can physically talk about this one, it is observable rigourously, and the other BH gains mass by absorbing it.

    You have two BHs in a box : they emit and absorb each other's radiations, exchanging mass if you will. This is a very interesting situation.
    But no paradox I see :smile:
    Last edited: May 23, 2008
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