Holographic reconstruction of bubble spacetimes

We discuss the holographic reconstruction of static thin bubble walls in Banados, Teitelboim, and Zanelli (BTZ) black hole geometries. We consider two reconstruction prescriptions suggested in recent years: hole-ography and light-cone cuts, in the context of thin bubble walls, and comment on their applicability in the presence of nontrivial matter in the bulk. We find that while the light-cone cuts prescription goes through within its own limitations, the current hole-ographic approaches are inadequate to describe bubble spacetimes completely. Much as entanglement shadows found around BTZ black holes and conical defects in the bulk, we find that thin bubbles are accompanied by shadows of their own, which are regions of spacetime that are only partially probed by minimal geodesics. We speculate that such shadows might be a generic feature of the presence of matter in the bulk.