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Reversing a black hole

  1. Feb 15, 2010 #1
    Hello, before I state my question I should say that I am a biologist and not a physicist. A thought about the speed of light and black holes crossed my mind however. A black hole's gravitational pull is so great that even light cannot escape it. I was under the impression that nothing can move faster then light yet a black hole can pull with enough force to effectively pull light into its center. If one were to create an equal but opposite pushing force, could that not accelerate something faster then the speed of light?


  2. jcsd
  3. Feb 15, 2010 #2


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    Black holes - and more generally, gravity - do not pull with a force. More accurately, what they do is bend spacetime. Light follows curved spacetime just like matter does.

    This also shows why there is no counter-force to gravity. Gravity is curved spacetime. Lack of gravity is flat spacetime. There is nothing flatter than flat, so there is no way to have a counter-gravity.
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