On the boundary gauge dual of closed tensionless free strings in AdS

TL;DR

This work analyzes closed tensionless strings in $AdS_d$ and derives an exact boundary-boundary propagator, revealing that boundary dynamics are frozen and can be interpreted as Wilson loop configurations in a confining phase. By embedding $AdS_d$ in a flat ambient space and applying a partial gauge fixing, the authors reduce the problem to the boundary $d-1$ dimensional Minkowski space and identify two conjugate boundary pictures: Singular Polyakov Strings with a singular worldsheet metric and Condensed strings with a chiral constraint that eliminates nontrivial boundary evolution. The central result is a gauge-dual interpretation: the boundary theory corresponds to a weakly coupled abelian $(d-4)$-form theory, with the tensionless string boundary correlator matching the correlator of two conjugate Wilson loops in the strongly coupled compact abelian theory, via a Polyakov monopole condensation framework. These findings offer a concrete realization of holography in the tensionless limit and suggest BRST-guided links to higher-spin structures and future second-quantized string field formulations.

Abstract

We consider closed free tensionless strings in $AdS_d$, calculate exactly the boundary/boundary string evolution kernel and find the string dynamics to be completely frozen. We interpret therefore the boundary configurations as Wilson loop operators in a confining phase. This is taken as an argument in favor to the dual weakly coupled abelian gauge theory being that of $(d-4)$-forms in the $(d-1)$ dimensional boundary Minkowski space.