Functional BES equation

Understand

We give a realization of the Beisert, Eden and Staudacher equation for the planar N=4 supersymetric gauge theory whichseems to be particularly useful to study the strong coupling limit.

• We use a linearized version of the BES equation as two coupled equations involving an auxiliary density function.
• We write these equations in terms of the resolvents and we transform them into to a system of functional, instead of integral, equations.
• We solve the functional equations perturbatively in the strong coupling limit and reproduce the recursive solution obtained by Basso, Korchemsky and Kotanski.