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Puzzling Question

  1. Mar 24, 2008 #1
    You cross the event horizon of a black hole and send that black hole traveling towards a star. When the black hole is in orbit around the star, you (assuming that you can) exit the black hole at the same time as when you entered it. What happens? Is that possible?

    From what I understand about black holes, when you have crossed over the event horizon, the dimensions of space collapse to a point, and the only direction that you can move in is time. I asked my self the above questions and I don't know what to make of it.
  2. jcsd
  3. Mar 24, 2008 #2


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    Hi Ironlenny,
    Once something has crossed the event horizon, it can never get out of the black hole. What is happening on the inside is a matter for speculation, since we haven't found any black holes, and even if we did we couldn't interact with the interior.

    This is a short answer, but you can use the search menu ( top toolbar) to find other discussions about black holes in this forum.

    Last edited: Mar 24, 2008
  4. Mar 24, 2008 #3
    I was under the impression that we have observed phenomenon that behave as we'd expect a black hole to behave. Since they behave like black holes, I believe it's reasonable to assume that they are black holes.

    I am curious about your comment on speculation. It seems to imply that a question that can't be answered with our current level of knowledge shouldn't be asked. I want to know how time dilation would effect an object inside the event horizon of a black hole that was accelerated to a fraction of the speed of light. I don't care that it is speculation. I am asking the question for the sake of asking it.

    I would also like to point out that you can interact with the interior of a black hole, but you can't send out any information. If you orbit a black hole above the event horizon and send a probe, it will send telemetry right up to the point that it crosses over.
  5. Mar 24, 2008 #4


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    Fair enough, but it's not direct evidence.

    Why so defensive ? I wasn't criticising your question. I just don't want to take part in speculation.

    If you can't receive any data from the region, you're not interacting. Maybe 'interacting' is a bad choice of word.

    (my emphasis).
    Which supports my point that we can't know directly what's across the horizon.
  6. Mar 24, 2008 #5
    I realize that you are trying to help, but I am interested in speculation.
  7. Mar 24, 2008 #6


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    I'm sure someone will speculate with you in time. Try searching other threads in the meantime.
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