Is it possible for two black holes to collide perfectly?

Question

If two blackholes with exactly the same mass, are traversing the universe on a perfect collision course with no other gravitational force effecting either black hole, what would happen to both black holes?

Would they merge in to one larger blackhole?

If there is an answer for a blackhole with zero accretion disk, I don't understand how a merge would be possible.

Answer 1

Dear Luke,

As I understand it, the two black holes would merge, without generating any accretion disk. Accretion disks only form from matter falling towards a black hole; all the mass is already inside the respective black holes and cannot emerge, even as the two event horizons merge. There could be some gravitational waves generated; a sufficient collision course only allows the event horizons to merge, it's unlikely that even at that the two objects are "perfectly" aligned (would you like to get up close to check?). -- Mr. d.

Answer 2

Dear Luke,

As I understand it, the two black holes would merge, without generating any accretion disk. Accretion disks only form from matter falling towards a black hole; all the mass is already inside the respective black holes and cannot emerge, even as the two event horizons merge. There could be some gravitational waves generated; a sufficient collision course only allows the event horizons to merge, it's unlikely that even at that the two objects are "perfectly" aligned (would you like to get up close to check?). -- Mr. d.