ABSTRACT:

Black holes are conjectured to be the fastest quantum scramblers in nature, with the stretched horizon being the scrambling boundary. Under this assumption, we show that any infalling body must couple to virtually the entire black hole Hilbert space even prior to the Page time in order for there to be any hope of preserving the often-cited claim of the equivalence principle that such bodies should experience `no drama' as they pass a black hole's horizon. Further, under the scrambling assumption, we recover the usual firewall result at the black hole's Page time for an initially pure-state black hole without the need for any complexity or computational assumptions. For a black hole that is initially impure, we find that the onset of the firewall is advanced to times prior to the standard Page time. Finally, if black holes really do efficiently scramble quantum information, this suggests that, in order to preserve this claim of the equivalence principle even prior to the onset of a full-blown firewall, the quantum state of a black hole interior must be a Bose-Einstein condensate.