Bootstrapping bulk locality. Part II: Interacting functionals

TL;DR

This paper develops complete sum rules for bulk operator reconstruction in AdS/CFT, enabling explicit solutions to the locality problem in strongly interacting quantum field theories.

Contribution

It introduces a framework of interacting functionals and sum rules that are dual to sparse CFT spectra, advancing the understanding of bulk locality in AdS/CFT.

Findings

Constructed complete sum rules for bulk operator reconstruction.

Proved a Paley-Weiner type theorem for sum rule spaces.

Enabled explicit, exact solutions to the locality problem.

Abstract

Locality of bulk operators in AdS imposes stringent constraints on their description in terms of the boundary CFT. These constraints are encoded as sum rules on the bulk-to-boundary expansion coefficients. In this paper, we construct families of sum rules that are (i) complete and (ii) `dual' to sparse CFT spectra. The sum rules trivialise the reconstruction of bulk operators in strongly interacting QFTs in AdS space and allow us to write down explicit, exact, interacting solutions to the locality problem. Technically, we characterise `completeness' of a set of sum rules by constructing Schauder bases for a certain space of real-analytic functions. In turn, this allows us to prove a Paley-Weiner type theorem characterising the space of sum rules. Remarkably, with control over this space, it is possible to write down closed-form `designer sum rules', dual to a chosen spectrum of CFT operators meeting certain criteria. We discuss the consequences of our results for both analytic and numerical bootstrap applications.