On the semiclassical three-point function inAdS3

Abstract

We reconsider the problem of determining the semiclassical three-point function in the Euclidean ${\mathrm{AdS}}_{3}$ model. Exploiting the affine symmetry of the model, we use solutions of the classical Knizhnik-Zamolodchikov equation to compute the saddle point of the action in the presence of three vertex operators. This alternative derivation reproduces the ``heavy charge'' classical limit of the quantum three-point correlator. It is different from the recently proposed expression obtained by the generalized Pohlmeyer reduction in ${\mathrm{AdS}}_{2}$.