Massless S matrices for AdS3/CFT2

The AdS3/CFT2 correspondence features massless non-relativistic modes on the string worldsheet in lightcone gauge. We study in detail these excitations and highlight how they naturally split between chiral (left-moving) and anti-chiral (right-moving) representations. In light of this split we discuss the constraints on the two-particle worldsheet S matrix imposed by braiding and physical unitarity, parity, time-reversal, and crossing invariance. We also comment on the implication of this split in the mirror kinematics.

Automated summary

This paper studies the properties of non-relativistic modes in the AdS3/CFT2 correspondence in lightcone gauge. These modes naturally split into chiral and anti-chiral representations. The constraints on the two-particle worldsheet S matrix are discussed in light of this split, including braiding, physical unitarity, parity, time-reversal, and crossing invariance. The implication of this split in the mirror kinematics is also commented on.