Penrose diagram for collapse in AdS. The vertical solid line represents the AdS boundary, the vertical dashed line the AdS origin, and the upper wavy curve the curvature singularity, produced by a null shell which originates on the boundary at time (CFT dual of this process is discussed in Section 6.1.2), and collapses to zero area. In the bulk, event horizon (dashed diagonal blue line) nucleates at bulk time , whose signal can be seen by bulk-cone singularity with one insertion at and the other at .
