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Homework Help: Black hole question

  1. Sep 11, 2003 #1
    Why is it said that a black hole is a literally bottemless pit in space-time? If it weren't bottemless, then the singularity inside would not have to be of infinite density.

    I'm not sure if I have missed anything important, so PLEASE help!
     
  2. jcsd
  3. Sep 11, 2003 #2

    HallsofIvy

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    Science Advisor

    Yes, but a black hole is, by definition, of infinite density.\\


    Well, the way you are putting it, that's true. In general, a black hole only has to be massive enough that light cannot escape it. (It's "escape velocity" is greater than the speed of light.)

    A large (in volume) black hole would not have to have infinite density and would not be "a literally bottemless pit in space-time".
     
  4. Sep 11, 2003 #3
    What do you mean by "density" ?
    Huh ?
    mass/volume ?
    mass=finite
    volume<>0...(the radius of the horizon is not 0...)
    so density is not infinite...or am I wrong ?
     
  5. Sep 12, 2003 #4
    I think he was talking about the singularity's density.
     
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