Main Question or Discussion Point
I'd like to understand the details behind the LIGO experiment a bit better:
- How do scientists know that the gravitational waves detected by LIGO originated from two specific black holes (located a billion light years away)?
- Does the LIGO result confirm the existence of black holes?
- Was it only after gravitational waves were detected by LIGO, that scientists tried to figure out from which location the gravitational waves originated? i.e. post-hoc deduction
- There was a "dud" gravitational wave detection in 2014 by the BICEP2 telescope located at the South Pole. What makes scientists so confident this time that the LIGO results aren't a dud?