I don't know if this is too technical for me, but Wikipedia says . . .
"The Final Parsec Problem
"The natural separation of two supermassive black holes at the center of a galaxy is a few to a few tens of parsecs (pc). This is the separation at which the two black holes form a bound, binary...
(1) Maybe should've messanged this, but given LIGO, the FAQ might need a light edit. It says,
"Gravitational waves have never been detected directly, but the loss of energy from the Hulse-Taylor binary pulsar has been checked to high precision against GR’s predictions of the power emitted in...