Thread: What if a black hole passes near another black hole?

Would it be possible for them to rip matter away from each other?

I don't think it would be possibly for black holes to rip matter out of the event horizon of each other, but outside of the event horizon I think it would depend on the mass of the individual black holes. Depending on the speed of the travelling through space black holes and the distance that they pass each other by it may lead to a capture and the black holes'll merger.

Scientists have theorized...that the central black hole in the Andromeda galaxy, merged with or cannibalized with it's sister black hole; which should have been a very large BH. Billions of years from now, our sister galaxy --- Andromeda --- will collide with our Milky Way galaxy --- and I theorize that they {center super-massive BH's} of both galaxy's --- will merge or cannibalize with one or the other.

By "theorise" I take it you mean "guess"?

In the space between the black holes, there would be less gravitational force. But apparently the time dilation effect remains present. So even if the matter were being pulled out of one black hole into another, it would be moving according to its own local perspective of time - which means we'd observe from outside that it wasn't moving at all.


But I don't a black hole could get that close to another black hole without the two merging. Remember gravitational acceleration doesn't depend on the mass of the object being accelerated, so they would probably get pulled into each other. .

Originally Posted by kojax

In the space between the black holes, there would be less gravitational force. But apparently the time dilation effect remains present.

Because the gravitational forces of the two black holes might cancel out but spacetime is still highly curved.

But I don't a black hole could get that close to another black hole without the two merging. Remember gravitational acceleration doesn't depend on the mass of the object being accelerated, so they would probably get pulled into each other. .

Some good animations of black hole mergers here:
black-holes.org—Movies of Extreme Spacetimes
(I would start with the one at the bottom of the page as it is simplest.)