A light-cone approach to three-point functions in AdS_5 x S^5

TL;DR

This paper develops a light-cone gauge approach to compute three-point functions in AdS_5 x S^5 string theory, analyzing BMN and winding strings, and connects these results with gauge theory structure constants.

Contribution

It introduces a light-cone worldsheet method for calculating three-point functions in AdS_5 x S^5, including saddle-point and fluctuation analyses, and links string theory results with gauge theory calculations.

Findings

Computed saddle-point three-point functions for BMN operators.

Analyzed fluctuation spectra depending only on total charge.

Extended calculations to near-BMN operators and connected to gauge theory.

Abstract

We consider worldsheet correlation functions for strings in AdS_5 x S^5 using a light-cone gauge for the worldsheet theory. We compute the saddle-point approximation to three-point functions of BMN vertex operators, all with large charges, by explicitly finding the intersection of three euclidean BMN strings. We repeat this calculation for non-BPS circular winding strings extended along a great circle of the S^5, though in this case the appropriate form of the vertex operator is uncertain. Furthermore, we compute the spectrum of fluctuations about euclidean BMN strings for generic boundary conditions, and show that the spectrum depends only on the total charge and not the details of the string configuration. We extend our considerations to include near-BMN vertex operators and through the evaluation of the string path integral make contact with the light-cone string field theory calculations of gauge theory three-point structure constants.