Comment by daxfohl
One odd thing that never occurred to me until now is that two black holes that pass each other at near light speed, if they intersect by even a nanometer, will be guaranteed to merge. That nanometer has to fall into both singularities due to the properties of black holes, so transitively they have to merge. Kind of weird. I'm guessing it would create a bunch of angular momentum and throw out almost all their masses as gravitational waves. Will be a fun experiment for someone in a few hundred years.
> I'm guessing it would create a bunch of angular momentum and throw out almost all their masses as gravitational waves. Will be a fun experiment for someone in a few hundred years.
I'm not a physicist but it sounds to me like a gravitational bomb. I wonder how it will affect its surroundings? Stars being torn apart? I wouldn't like to watch such an experiment in person. Though if someone tried it a couple billions light years away from me, and then sent a video record, I'm all for it. I'd prefer to wait a couple billions years for the record to be downloaded, than to watch an online stream.