Rotating deformations of AdS_3\times S^3, the orbifold CFT and strings in the pp-wave limit

TL;DR

This paper constructs exact geometries in AdS_3×S^3, compares their excitation spectra with dual CFT states, and proposes a string-CFT state mapping, deepening understanding of AdS/CFT correspondence in this setting.

Contribution

It introduces new exact solutions in AdS_3×S^3, matches their spectra with dual CFT states, and proposes a novel string-CFT mapping similar to known AdS_5×S^5 results.

Findings

Exact geometries match CFT excitation energies

Redshift reproduces 'long circle' physics in CFT

Proposed map between string states and orbifold CFT states

Abstract

We construct an exact metric which at short distances is the metric of massless particles in 5+1 spacetime (moving along a diameter of the sphere) and is AdS_3\times S^3 at infinity. We also consider a set of a conical defect spacetimes which are locally AdS_3\times S^3 and have the masses and charges of a special set of chiral primaries of the dual orbifold CFT. We find that excitation energies for a scalar field in the latter geometries agree exactly with the excitations in the corresponding CFT state created by twist operators: redshift in the geometry reproduces `long circle' physics in the CFT. We propose a map of string states in AdS_3\times S^3\times T^4 to states in the orbifold CFT, analogous to the recently discovered map for AdS_5\times S^5. The vibrations of the string can be pictured as oscillations of a Fermi sea in the CFT.