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Could you pull someone out of a black hole?

  1. Sep 26, 2008 #1
    Suppose you had a very, very large black hole, so large that the tidal forces at or near the event horizon were not fatal. If you lowered someone down via a very long indestructible cable past the event horizon, and you held your spaceship sufficiently far away from the black hole to ignore its gravity, would it be possible to pull the person back out? When you account for the effects of relativity, would the force required to do so be infinite?
  2. jcsd
  3. Sep 26, 2008 #2


    Staff: Mentor

    An indestructible cable is no more compatible with relativity than a perfectly rigid rod.
  4. Sep 27, 2008 #3


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    Staff Emeritus
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    Gold Member

    The thrust that the rocket's engines must produce to keep this person at a constant distance from the event horizon goes to infinity as the distance goes to zero. So it isn't even possible to lower someone down slowly.
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