Hybrid-NLIE for the AdS/CFT spectral problem

Understand

Hybrid-NLIE equations, an alternative finite NLIE description for the spectral problem of the super sigma model of AdS/CFT and its gamma-deformations are derived by replacing the semi-infinite SU(2) and SU(4) parts of the AdS/CFT TBA equations by a few appropriately chosen complex NLIE variables, which are coupled among themselves and to the Y-functions associated to the remaining central nodes of the TBA diagram.

• The integral equations are written explicitly for the ground state of the gamma-deformed system.
• We linearize these NLIE equations, analytically calculate the first correction to the asymptotic solution and find agreement with analogous results coming from the original TBA formalism.
• Our equations differ substantially from the recently published finite FiNLIE formulation of the spectral problem.