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One black hole in another?

  1. Jul 21, 2004 #1
    Can a mini black hole exist as a black hole, inside a black hole of a few solar masses? If so,would this mean that we would not only be ignorant of the evolution of the microstates of the mini black hole as time passes - we would also be ignorant of the evolution of the total mass, angular momentum and charge of the mini black hole - can a mini black hole disappear without trace
    from observers outside a large black hole?
  2. jcsd
  3. Jul 21, 2004 #2


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    a partial answer:
    the ordinary GR theory in which black holes were first predicted
    allows black holes to collide and merge

    and people do numerical GR simulations of that kind of thing on computers
    on the web you can see comic strip sequences of computergenerated pictgures of black holes colliding

    I dont see any reason a little BH couldnt fall into a big one, and because of timedilation troubles we on the outside might not actually be able to see it fall thru the horizon

    but in "reality" whatever that means the little black hole would exist inside the big one and, I guess, be succcckkkked into the center of the big one and slurped. And I guess the computer people could easily simulate that and crank out pictures of it happening.

    essentially the little black hole would be falling in just the way a lot of other stuff is falling in----stones, old copies of Time magazine, cast-off Television sets, and whatever else.
  4. Jul 22, 2004 #3
    One of the moderators on sci.physics.research says that a small black hole in a big one is not meaningful because the schwarzschild metric is a unique and spherically symmetric solution for a black hole - do you agree with this?
  5. Jul 22, 2004 #4


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    well I defer to any experts, but the schw metric is a static solution that describes a black hole that looks exactly that way forever

    I dont imagine one could have a static situation with a little BH inside the horizon of a big BH

    But I can imagine a dynamic situation in which BHs collide and merge (producing a wonderful brief storm of gravity waves as they do)

    and I can picture a little BH falling towards a big one----on its way to eventual destruction----and their horizons merging amoeba-style as the little one is eaten----and it seems to me that at least temporarily there should be two singularities inside the large one's horizon

    it this is impossible mathematically then there's a clearcut issue to discuss here and obviously my intuitive picture is wrong, but I need a good link to something on the web to show me that---do you have the SPR Cornell archive link to that?
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