Solvable time-like cosets and holography beyond $AdS$

TL;DR

This paper constructs a new time-like coset sigma-model for type-II superstrings in a charged rotating black-brane background, enabling the study of holography beyond AdS, with results matching a Tar{T}-deformed CFT2 spectrum.

Contribution

It introduces a novel solvable sigma-model interpolating between AdS3 and linear-dilaton geometries, advancing holography in non-AdS backgrounds.

Findings

Spectrum of long strings matches Tar{T}-deformed CFT2

Computed two-point correlation functions in non-AdS background

Established holographic correspondence in a new interpolating geometry

Abstract

We build a novel time-like coset sigma-model describing type-II superstring theory in a charged rotating black-brane background that interpolates between a locally $AdS_3$ in the IR and a linear-dilaton geometry in the UV. This allows one to perform a systematic study of holography in non-AdS backgrounds which are smoothly connected to $AdS_3$. We construct massless closed string states vertex operators in the NS-NS sector, calculate the corresponding two-point correlation functions, and discuss holographic interpretation of our results from 4+1 dimensional boundary field theory point of view. Compactifying the theory on $\mathbb{T}^4$, we show that the spectrum of a single long string with unit winding agrees with the spectrum of a CFT$_2$ deformed by $T\bar{T}$. We also calculate correlation functions of operators of the dual 1+1 dimensional non-conformal boundary field theory using world-sheet techniques.