Banerjee and Vos's analytic AdS3/CFT2 study of bulk black-hole formation: computing the real-time two-into-two scattering amplitude of conical defects as the self-overlap of a two-heavy-operator state, obtained from a systematic approximation of the monodromy problem for the semiclassical Virasoro blocks of the four-point all-heavy (HHHH) correlator at large central charge. Dialing the external scaling dimension drives a transition from a scattering phase to an intermediate black-hole phase; this transition occurs before the individual heavy operators exceed the BTZ mass gap, which the authors attribute to energy stored in Brown-Henneaux boundary charges rather than kinematics alone.
Working in the AdS3/CFT2 holographic correspondence, this paper computes the real-time (Lorentzian) bulk AdS3 two-into-two scattering amplitude of conical defects as the self-overlap of a two-heavy-o…