It is widely believed that long after gravitational collapse, the external geometry of black holes relaxes to the Kerr-Newman solution. In contrast, the interior geometry is not unique and depends on initial conditions. I will discuss universal features of the interior of one-sided black holes in asymptotically flat space with a scalar field. In particular, I will argue that generically there exists effective gravitational shocks at the would-be inner horizon, a singular Cauchy horizon, and a spacelike singularity at r = 0.
Gravity Initiative Lunch, Paul Chesler | Harvard "Internal geometry of black holes"