: What would happen if two black hole event horizons crossed? I would speculate that a "Big Bang" type event. All this would happen in a pretty short period of time once the two horizons meet. They would create an even greater force on the two central black hole masses than they independantly exert. The mass/energy of the two holes would get pulled into the void they created and everything pretty much collides with lots of other stuff and then these huge waves of enegy/matter go out from this event forming anew a universe? Whatcha think? By the way if you have any credentials I would appreciate being told of them.

: This sounds interesting, but there is probably little to support it. First, for the observer, one black hole would NEVER cross the event horizon of the other one; this is because of time dilation effects at the event horizon. Of course, the black holes would actually merge very quickly, but we would not be lucky enough to observe it. Next, unless the black hole singularities were aimed PRECISELY at one another, they would enter an orbit around each other, whether within or outside of the event horizon. Depending on the size of the event horizon, the orbital period could be extremely rapid or very slow, but probably the former (most event horizons aren't very big, except for supermassive black holes like those in the galactic centers). The orbit would probably decay quickly, but while they were in there the event horizon would expand to encompass both singularities in response to their combined gravity, probably being able to swallow up any additional energy effects that could come from the actual collision of the black holes. And then, why should the energy be released upon collision? It is bound up very tightly with the matter in there, and the increase in the energy would be no more than if two stars of the same mass as the black hole collided themselves. The grip of a black hole is very strong, and the enrgy isn't likely to come out, let alone tear another hole in the virtual fabric that may have resulted in the first Big Bang. Oh sure, none of this means a lot, and it frankly isn't very scientific, but a Big Bang is a special event that requires unusual circumstances that have not existed in our neck of the woods for 12,000,000,000 years. Whatever created the Big Bang probably didn't require a black hole to do it originally, but probably more of a chance occurrence.

Not only that, but if there are supermassive black holes in the galactic centers, and they have been swallowing glaactic hub stars for eons, and those stars have been going through the same supernova processes that other stars have, don't you think that a few black holes have already merged in these highly concentrated areas? No galaxies that I know of have yet resulted in a Big Bang...Bruce