AdS/CFT beyond inter-representational dualities

Abstract

In Jaksland and Linnemann (2020), it was claimed that the AdS/CFT correspondence is simply about two different ways of utilizing the same string theory on the anti-de Sitter (AdS) side. While this was traditionally so, with both string theory and conformal field theory (CFT) being local physics, recent developments in holographic gravity - holography of information and the islands proposal - complicate the story, with more roles played by non-locality and CFT. Some of these developments allow for interpreting AdS/CFT as a mapping from CFT predictions to observational reality in a bulk space, rather than just being an inter-representational duality. Two key questions - whether string theory is non-local and whether the Hilbert space of string theory is smaller than that of CFT - remain unsettled, as with the charge that these new developments are wrong extrapolations of AdS/CFT, conflating non-local mapping with theories being non-local. Given this state of affairs, it would be inappropriate yet to conclude that AdS/CFT is holography without holography.