Machine code of holography

Gauge-gravity duality plays a key role in understanding quantum gravity and strongly interacting gauge theories, however, lacks a satisfactory microscopic derivation. Fundamental questions such as, how does gravity emerge directly from quantum field theory observables and how to determine which QFTs are holographic, which are not, remain unanswered. In this talk, I propose a primitive form of gauge-string duality based on the worldline formulation of perturbative QFT. In particular we consider L loop quantum corrections to correlation functions in an holographic QFT where a Schwinger parameter is associated to each internal propagator in the corresponding Feynman diagrams. We argue that embedding of the holographic coordinate in string theory emerges from the collection of these Schwinger parameters in the continuum limit of the Feynman diagrams. As a by product, we provide a novel Kallen-Lehmann representation of two-point functions as a sum over boundary-to-boundary propagators of massive bulk scalars in AdSd+1 with masses determined by L. This novel approach can be generalized to arbitrary N. Therefore it might have two potential uses: to provide  i) a non-perturbative approach to quantum gravity in terms of perturbative QFT at finite N, ii) a true bottom-up holographic construction for confining gauge theories like QCD derived directly from QCD amplitudes.