Naked Science Forum

Non Life Sciences => Physics, Astronomy & Cosmology => Topic started by: Eric A. Taylor on 06/12/2009 18:25:36

Title: Can a black hole event horizon be pulled out of round?
Post by: Eric A. Taylor on 06/12/2009 18:25:36

Black holes sometimes merge with each other. Just before they merge are the event horizons pulled out of round making the black hole egg shaped. If the two event horizons begin to touch will the black holes become hour glass shaped?

What about merging neutron stars.

Title: Can a black hole event horizon be pulled out of round?
Post by: Mr. Scientist on 06/12/2009 19:33:23

Quote from: Eric A. Taylor on 06/12/2009 18:25:36

Black holes sometimes merge with each other. Just before they merge are the event horizons pulled out of round making the black hole egg shaped. If the two event horizons begin to touch will the black holes become hour glass shaped?

What about merging neutron stars.

It would be stretched from one end to another until one of the ends meet. If they rotate, they might form a swirling effect, before shattering the spacetime fabric and releasing all those gravitational waves. :)

Title: Can a black hole event horizon be pulled out of round?
Post by: Mr. Scientist on 06/12/2009 19:34:38

And i'm not sure about neutron stars. They may just collide and release massive amounts of energy, rather than completely merging.

Title: Can a black hole event horizon be pulled out of round?
Post by: LeeE on 07/12/2009 01:47:58

The Event Horizon marks the point where the gravitational gradient reaches a certain point, so yes, the shape need not be spherical.

There is no problem with neutron stars merging, as long as they're both matter (or anti-matter); they're just made out of neutronium.  Neutron stars are not dense enough, and merging doesn't increase their density enough either, to form an Event Horizon i.e. the gravitational gradient they produce isn't steep enough.