ar X iv : g r - qc / 9 90 20 08 v 1 2 F eb 1 99 9 The Inner Structure of Black Holes

We study the gravitational collapse of a self-gravitating charged scalar-field. Starting with a regular spacetime, we follow the evolution through the formation of an apparent horizon, a Cauchy horizon and a final central singularity. We find a null, weak, mass-inflation singularity along the Cauchy horizon, which is a precursor of a strong, spacelike singularity along the r = 0 hypersurface. The inner black hole region is bounded (in the future) by singularities. This resembles the classical inner structure of a Schwarzschild black hole and it is remarkably different from the inner structure of a charged static Reissner-Nordström or a stationary rotating Kerr black holes. The simple picture describing the exterior of a black-hole [1] is in dramatic contrast with its interior. The singularity theorems of Penrose and Hawking [2] predicts the occurrence of inevitable spacetime singularities as a result of a gravitational collapse in which a black-hole forms. According to the weak cosmic censorship conjecture [3], these spacetime singularities are hidden beneath the black-hole’s event-horizon. However, these theorems tell us nothing about the nature of these spacetime singularities. In particular, the final outcome of a generic gravitational collapse is still an open question. Our physical intuition regarding the nature of these inner singularities and the outcome of gravitational collapse is largely based on the spherical Schwarzschild black hole solution and the idealized Oppenheimer-Snyder collapse model [4]. The Schwarzschild black hole contains a strong spacelike central singularity. All the matter that falls into the black hole