Editing Openai/6897769e-4ee4-800f-aba5-69cca34f701c (section)

==== 1. AdS vs dS / flat spacetime Holography is best understood for asymptotically AdS spacetimes. Our universe is approximately flat or de Sitter, so mapping QAT (which is meant to be generic) to real cosmology requires either: (i) working in an AdS toy model and hoping the mechanism generalizes, or (ii) using more speculative dS/cosmic holography techniques (less developed). So start in AdS toy models. ====
# Large-N / classical gravity limit The emergence of a classical bulk geometry requires a boundary theory with a large parameter (e.g., large N) so that 1/N corrections are small. QAT’s microscopic atomic physics is not obviously a large-N CFT; you'd need to identify an effective large parameter (e.g., many boundary modes per shell) or consider an effective coarse-grained CFT.
# Microscopic dictionary You must define precisely which boundary operators represent photon exchange and how their correlators are computed from QAT microphysics. That mapping is the heart of the program and requires clear operator definitions.
# Time emergence vs holographic radial direction In many holographic setups the radial coordinate is interpreted as a scale (RG flow) rather than a time. QAT emphasizes emergence of time from boundary events. Bridging that interpretational gap needs careful thought: one approach is to treat the state of the boundary CFT (and its time evolution) as primary; the dual bulk time coordinate emerges from the pattern of entanglement and operator dynamics.