Integrable crosscaps in classical sigma models

We study the integrable boundaries and crosscaps of classical sigma models. We show that there exists a classical analog of the integrability condition and KT-relation of the boundary and crosscap states of quantum spin chains. We also classify the integrable crosscaps for various sigma models including examples which are relevant in the AdS/CFT correspondence at strong coupling.

Automated summary

This paper investigates the integrable boundaries and crosscaps of classical sigma models. It demonstrates the existence of a classical analog of the integrability condition and KT relation for the boundary and crosscap states of quantum spin chains. Moreover, it classifies the integrable crosscaps for various sigma models, including those relevant to the AdS/CFT correspondence at strong coupling.