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Black Holes and Gravity

  1. Nov 15, 2013 #1
    Hi guys,

    Simple question for my first post.

    If nothing escapes Black Holes, how come they're such massive gravity pools?

    While I can accept that in certain cases the gravity may come from all the mass near the event horizon that did not yet got through (center of Galaxies where it constantly swallows stars), what about wandering Black Holes that don't have a ready supply of matter around them?

    Does this mean that the gravitons / gravity waves travel faster than c?

  2. jcsd
  3. Nov 15, 2013 #2


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    Odd question ... nothing escapes because they ARE such massive "gravity pools" as you call them.

    The mass is INSIDE the event horizon and has nothing to do with whether or not the black hole is still feeding.

    I understand your question, I think. Because nothing can escape a black hole, you wonder how it is that the mass inside the black hole can have any effect outside the EH. This is more complicate than I can deal with but has been discussed on this forum many time. Try a forum search.

    NOT a good idea on this forum to suggest that anything can travel faster than c.
  4. Nov 15, 2013 #3
    Thanks, phinds. You perfectly understood my predicament.

    I did a search but I might not have used the correct keywords. I'll try again and be more patient going through the results, I might have overlooked.
  5. Nov 19, 2013 #4
    You mean how can gravity escape the black hole?

    Well, gravity isn't matter. It is a distortion in space-time. Gravity simply "is"
  6. Nov 20, 2013 #5


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    Gravity is a result of the curvature of the metric of spacetime. But the metric isn't "something" in the sense that light or matter is "something". It's the framework everything else is within. As such, nothing is escaping the black hole.

    No. Gravitational waves travel through the metric at c. They also travel through black holes. (Or another way to look at it is that the gravitational wave warps the event horizon in a way that it emits the same wave. At least that's what's been explained to me)
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