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The big bang and black holes

  1. Dec 13, 2005 #1
    I am just wondering about the big bang theory. If galaxies are travelling away from us at great speeds, what about the black holes? Where does black holes fit into the big bang theory? Could it be possible black holes can be the opposite of a sun, despite it's gravitational pull?
  2. jcsd
  3. Dec 13, 2005 #2
    The big bang and black holes are independent of each other. Black holes are collapsed stars that have their mass collapsed past a cerain point defined by the Schwarzchild Radius equation

    R= 2GM/c^2

    Where M is the mass collapsing down to the event horizon which is the radius we are defining
  4. Dec 22, 2005 #3


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    In general (for this question), you can consider a black hole like any other star...black holes orbit the galactic center and are carried with the galaxy as space expands. A black hole is an object embedded in spacetime just like anything else. Granted, as you examine it closely, it's an object with some amazing properties, but it's not something separated from this universe.

    Not sure what you mean.
  5. Dec 22, 2005 #4


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    Stephen Hawking postulated the existence of primordial, substellar mass black holes that 'froze' out of the big bang mess due to slight density differences in the early universe. No observational evidence of these mighty midgits has been found to date [some of them should be evaporating via Hawking radiation by now]. This would not affect expansion. A black hole has no special properties, aside from it's very high density. Save for matter very nearby, the rest of the universe would treat them no different than any other gravitating object. [i.e., same as what Phobos said]
  6. Dec 23, 2005 #5
    diameter is 3km ,if our sun become a black hole.
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