Naked Science Forum

Non Life Sciences => Physics, Astronomy & Cosmology => Topic started by: mlandri on 29/08/2010 21:19:44

Title: Can one EVER escape from a black hole after passing the event horizon?
Post by: mlandri on 29/08/2010 21:19:44

I understand that the curvature of space-time past the event horizon of a black hole prevents matter and energy from escaping once it passes that threshold. However, does mother nature provide any "get out of jail free" cards that could allow matter or energy to escape even after it passes the event horizon. For example, consider orbiting black holes that are in the process of merging. At some point, as the two singularities draw closer together, can gravitationally neutral regions such as Lagrange points form at points in space closer to the singularities than their pre-merge event horizons. If so, could previously doomed matter or energy in those regions conceivably escape the gravity of both black holes. Thanks!

Title: Can one EVER escape from a black hole after passing the event horizon?
Post by: Soul Surfer on 01/09/2010 23:50:31

An interesting idea but I think that it is very unlikely that anything can escape from a pair of merging black holes.  The reason for this is quite simple.  The size of the event horizon is a linear function of the mass.  This means that for two equal mass black holes the size of the resultant hole is precisely twice the size of the single one and the gravitational gradient is smaller.  this means that the event horizon of the combined black hole will form BEFORE the two smaller holes combine so there will never be a time when material inside of one of the holes is outside of an event horizon. 

 this link gives a diagram that illustrates what happens.

Title: Can one EVER escape from a black hole after passing the event horizon?
Post by: mlandri on 02/09/2010 02:51:14

Thanks for the answer and link!

...Fascinating how the two event horizons interact.