Two event horizons in close proximity

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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?
 
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kurious said:
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?

Photons don't orbit at the event horizon. They unstably orbit at the Photon sphere.
 
When two black holes meet, they would most likely collapse into one. Similarly with lots of black holes touching.
 
DW said:
Photons don't orbit at the event horizon. They unstably orbit at the Photon sphere.

Can the orbit be stable in an idealized Schwarzschild black hole?
 
jcsd said:
Can the orbit be stable in an idealized Schwarzschild black hole?

No, that's actually the kind of hole I was referring to. For the ideal Schwarzschild hole the photon sphere is at
r_{ps} = \frac{3GM}{c^2}.
 

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