Free Field Theory as a String Theory?

TL;DR

This paper explores how free large N gauge theories can be reformulated as string theories by deriving the closed string moduli space from Feynman diagrams, suggesting a connection to string theory on AdS.

Contribution

It provides a systematic method to realize open-closed string duality in free gauge theories and shows how the string moduli space naturally emerges from field theory diagrams.

Findings

Closed string moduli space arises from Feynman diagram reorganizations.

The integrand on moduli space has features consistent with string theory on AdS.

Demonstrates a potential bridge between free gauge theories and string theories.

Abstract

An approach to systematically implement open-closed string duality for free large $N$ gauge theories is summarised. We show how the relevant closed string moduli space emerges from a reorganisation of the Feynman diagrams contributing to free field correlators. We also indicate why the resulting integrand on moduli space has the right features to be that of a string theory on $AdS$.