Restoring unitarity in the q-deformed world-sheet S-matrix

摘要: The world-sheet S-matrix of the string in AdS5 ×S 5 has been shown to admit a q-deformation that relates it generalization sine-Gordon theory, which arises as Pohlmeyer reduction superstring. Whilst this is fascinating development resulting not explicitly unitary. problem known for long time context S-matrices related quantum groups. A braiding relation often called “unitarity” actually only corresponds field theory unitarity when Hermitian analytic and group manifestly violate this. On other hand, overall consistency under bootstrap requires deformation parameter root unity consequently one forced perform “vertex” IRF, or SOS, transformation on states truncate spectrum consistently. In IRF formulation now manifest generalised are recovered two different limits. latter case, expanding Yang-Baxter equation we find tree-level Pohlmeyer-reduced should satisfy modified classical explaining apparent anomaly perturbative computation. We show form meshes perfectly with equations.