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Black Holes are Singularities . or vice versa?

  1. Jan 3, 2010 #1
    Black Holes are Singularities..... or vice versa?

    Ok so a Singularity is a place in space time where gravity or the things used to determine gravity become infinite. So does this mean that Black Holes are types of Singularities or Black Holes have Singularities in the center, or Black Holes and Singularities are the same thing?
  2. jcsd
  3. Jan 3, 2010 #2


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    Re: Black Holes are Singularities..... or vice versa?

    They're the same thing. The term 'black hole' is a way of explaining a singularity.

    edit: To clarify that a bit... the singularity is the 'heart' of a black hole. The hole itself begins at the event horizon, which is the radius from the singularity at which the escape speed is equal to light speed. You can't have one without the other.
    Last edited: Jan 3, 2010
  4. Jan 3, 2010 #3


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    Re: Black Holes are Singularities..... or vice versa?

    I disagree. The idea of black holes is fairly well established. However what goes on inside (singularity?) is an open question. General relativity and quantum theory need to work together, but they don't.
  5. Jan 3, 2010 #4


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    Re: Black Holes are Singularities..... or vice versa?

    Black holes and singularities are not the same thing.

    You can have singularities in general relativity that are not black holes. The best example is the Big Bang singularity.

    You can have event horizons in general relativity without any singularity. For instance, an observer with a constant acceleration has an event horizon.

    You can also have singularities without event horizons. The Big Bang singularity isn't hidden behind an event horizon.
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