[pdonis]

> Does GR predict that there would be any waves confined to the inside of the merged black hole?

Yes, but we would of course never observe those, and they would not reduce the externally measured mass of the merged hole.

[LegionMammal978]

Yes, of course there'd be no external effects. I was just curious, since the region between the event horizon and the singularity is an interesting place to think about, even if we're forever confined to predictions rather than real observations.