Understanding dynamical black hole apparent horizons

Understand

Dynamical, non-asymptotically flat black holes are best characterized by their apparent horizons.

• Cosmological black hole solutions of General Relativity exhibit two types of apparent horizon behaviours which, thus far, appeared to be completely disconnected.
• By taking the limit to General Relativity of a class of Brans-Dicke spacetimes, it is shown how one of these two behaviours is really a limit of the other.