This is a question I have had for many years, and I have never got a good answer for. I am hoping some of the bright minds here may help me to understand it more.
According to general relativity, if I am steady away from a black hole and my friend is falling towards a black hole, my friend looking back at me would see time speed up until the universe aged away. While I would see my friend stop in time and never reach the black hole.
So how then do astrophysicists detect gamma ray bursts of black holes colliding, when in our reference frame the 2 black holes should never meet.
According to general relativity, if I am steady away from a black hole and my friend is falling towards a black hole, my friend looking back at me would see time speed up until the universe aged away. While I would see my friend stop in time and never reach the black hole.
So how then do astrophysicists detect gamma ray bursts of black holes colliding, when in our reference frame the 2 black holes should never meet.