Strong cosmic censorship: the nonlinear story

Abstract

A satisfactory formulation of the laws of physics entails that the future evolution of a physical systemshould be determined from appropriate initial conditions. The existence of Cauchy horizons in solutionsof the Einstein field equations is therefore problematic and expected to be an unstable artifact of generalrelativity. This is asserted by the strong cosmic censorship conjecture, which was recently put into questionby an analysis of the linearized equations in the exterior of charged black holes in an expanding universe.Here, we numerically evolve the nonlinear Einstein-Maxwell-scalar field equations with a positivecosmological constant, under spherical symmetry, and provide strong evidence that mass inflation indeeddoes not occur in the near extremal regime. This shows that nonlinear effects might not suffice to save thestrong cosmic censorship conjecture.