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What Keeps A Black Hole Going?

  1. Apr 6, 2009 #1
    I saw the Naked Science special last night about black holes, and one of the scientists said that the idea that compact matter existing inside the blackhole is wrong. The matter exists in a 0 dimensional point = it has been crushed out of existence. So what keeps the black hole going? If the matter in the singularity doesn't exist anymore, why doesn't the spacetime that makes up the black hole simply "flatten" back out? Doesn't a massive object have to exist for the spacetime to bend?
  2. jcsd
  3. Apr 6, 2009 #2


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    I wouldn't say the matter was crushed out of existance at the singularity.
    In fact it's probably not useful to talk about anything inside the event horizon.

    A black hole has a surface (the event horizon) at a distance = 2Gm/c^2, anything inside this radius (give or take some quantum effects very close to it) is lost to the rest of the universe. Inside this surface the matter still has mass, and we can weigh the total mass of the black hole, but we can't know anything else about the material anymore.
  4. Apr 6, 2009 #3


    Staff: Mentor

    Mass, charge, and momentum (angular and linear)
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