“Albert Einstein didn’t like them.
To him, black holes were a bit of an embarrassment, as they compromised his dream of a “rational” nature, that is, natural phenomena that we could describe and quantify with the usual methods of science. According to this view, good scientific theories shouldn’t generate absurd (read: “irrational”) results.”
via Black Holes Orbiting Around Each Other Send Off Waves, : 13.7: Cosmos And Culture : NPR