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Getting inside a black hole

  1. Mar 11, 2009 #1
    Why couldn't an observer position himself at the balance point of the gravity between two black holes that are approaching each other, ride the balance point all the way inside the black holes, and thus observe the singularity without being destroyed?
    Thanks in advance.
  2. jcsd
  3. Mar 11, 2009 #2


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    Once inside one of the black hole he couldn't get out. Meanwhile the black holes will merge into one bigger black hole with the observer stuck there.
    Last edited: Mar 11, 2009
  4. Mar 12, 2009 #3
    Black holes rip apart anything that gets close to them. As said by "mathman", the two black holes will merge to form a bigger black hole and will rip you apart at the sub-atomic level. That means htat you will disintegrate.
  5. Mar 12, 2009 #4
    This is a rather interesting idea. It reminds me of the book Dragon's Egg where they used large masses to compensate for the gravity of a neutron star. If you put two black holes in orbit around each other their gravity should cancel out at the center. Also the added gravity should change the shape of the event horizons. 2 black holes of 3 solar masses at a distance of 17720.6 meters from each other would orbit each other in 0.00053 seconds, which would be "only" 105,992,640 m/s.

    If there were two black holes in such an orbit wouldn't the event horizons be reduced in the direction facing the center? If it were wouldn't it be then possible to "rescue" things that had gone past the event horizon? Tidal forces would make this practically impossible, but in theory would this work?
  6. Mar 12, 2009 #5
    Well I'd imagine anything thats already passed the event horison would be already have been pulled apart in every direction, so unless you like 'rescuing' atoms..
  7. Mar 12, 2009 #6

    George Jones

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    No, this isn't always true. Tidal forces decrease as the size of a black hole increases, so a person who falls inside a large enough black hole, like at the centre of the galaxy, would not even feel pain (from tidal forces) until well inside the event horizon.

    According to a quick calculation that I just did (done so quickly that it could be wrong), the transition point (for pain) is about 100,000 solar masses.
  8. Mar 12, 2009 #7
    Even though we kept a spot steady inside BH, we still need a lot of calculation and imagination to process the info, because the light paths are seriously affected by gravity and most lights may head toward the center of BH.
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