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Two event horizons in close proximity

  1. Jun 30, 2004 #1
    Two black holes of equal mass move together so their event horizons meet.
    How would a photon initially going around one horizon in a circle,know which horizon to go around when it comes to the place where the horizons meet?
    And if there were thousands of small black holes filling a large area of space, all with touching event horizons, how would the photon behave?
  2. jcsd
  3. Jun 30, 2004 #2


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    Photons don't orbit at the event horizon. They unstably orbit at the Photon sphere.
  4. Jun 30, 2004 #3


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    When two black holes meet, they would most likely collapse into one. Similarly with lots of black holes touching.
  5. Jun 30, 2004 #4


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    Can the orbit be stable in an idealized Schwarzchild black hole?
  6. Jun 30, 2004 #5


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    No, thats actually the kind of hole I was referring to. For the ideal Schwarzschild hole the photon sphere is at
    [tex]r_{ps} = \frac{3GM}{c^2}[/tex].
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