Correlators for tensionless strings on AdS3 orbifolds

A bstract The CFT dual of string theory on (AdS 3 × S 3 )/ ℤ k × $$ {\mathbbm{T}}^4 $$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:msup> <mml:mi>T</mml:mi> <mml:mn>4</mml:mn> </mml:msup> </mml:math> is believed to be described by the subspace of the symmetric orbifold of $$ {\mathbbm{T}}^4 $$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:msup> <mml:mi>T</mml:mi> <mml:mn>4</mml:mn> </mml:msup> </mml:math> that comprises the low-lying excitations on top of a certain reference state. (This ‘non-perturbative’ reference state lies in the twisted sector associated to the conjugacy class consisting of only k -cycles.) In a recent paper we confirmed this picture by analysing the worldsheet theory of the orbifold at the tensionless NS-NS point, and by showing that the perturbative worldsheet spectrum reproduces precisely the single particle excitations on top of this reference state. In this paper we explain that this identification also holds on the level of the correlators, at least to leading order in 1/ N .