The Bound State S-Matrix for AdS5 x S5 Superstring

TL;DR

This paper constructs the exact S-matrix for scattering of bound states in AdS5 x S5 superstring theory, using Yangian symmetry and superspace formalism, with implications for finite-size spectral problems.

Contribution

It introduces a new S-matrix construction for bound states based on Yangian symmetry, unifying previous results and aiding spectral analysis.

Findings

Reproduces known scattering matrices for specific bound states

Identifies hypergeometric function 4F3 as the analytic structure

Provides insights into the universal R-matrix for psu(2|2) superalgebra

Abstract

We determine the S-matrix that describes scattering of arbitrary bound states in the light-cone string theory in AdS5 x S5. The corresponding construction relies on the Yangian symmetry and the superspace formalism for the bound state representations. The basic analytic structure supporting the S-matrix entries turns out to be the hypergeometric function 4F3. We show that for particular bound state numbers it reproduces all the scattering matrices previously obtained in the literature. Our findings should be relevant for the TBA and Luescher approaches to the finite-size spectral problem. They also shed some light on the construction of the universal R-matrix for the centrally-extended psu(2|2) superalgebra.