Shock singularity
In general relativity, the shock singularity, also called the shockwave singularity, the Marolf-Ori singularity, or the outflying singularity, is a null singularity propagating out of the outgoing section of the inner horizon of a spinning or charged black hole that effectively manifests as a gravitational shockwave. Perturbations to the inner horizon result in abrupt changes in the amplitude of perturbing fields and the metric tensor itself, manifesting as an effective shockwave for sufficiently late-infall observers (veh⪆15-20).