Wronskian Solution for AdS/CFT Y-system
Nikolay Gromov, Vladimir Kazakov, Sebastien Leurent, Zengo Tsuboi
TL;DR
This work derives an explicit Wronskian determinant representation for the AdS$_5$/CFT$_4$ Y-system in the ${\mathbb T}$-hook, expressing the $T$- and $Y$-functions through a finite set of Baxter ${\mathsf Q}$-functions and a generating functional. By establishing QQ-relations and a complete set of determinant formulas, it reduces the problem to eight basis ${\mathsf Q}$-functions, paving the way for a finite-size nonlinear integral equation (FiNLIE) description of the spectrum. The construction connects the classical finite-gap / monodromy picture (via $SU(2,2|4)$ characters) to the quantum Y-system, and clarifies symmetry and analyticity properties, including mirror reality and wing-exchange. The results offer a concrete framework toward FiNLIE for the full planar AdS$_5$/CFT$_4$ spectrum and suggest extensions to operatorial Q-operators and related dualities such as ABJM.
Abstract
Using the discrete Hirota integrability we find the general solution of the full quantum Y-system for the spectrum of anomalous dimensions of operators in the planar AdS5/CFT4 correspondence in terms of Wronskian-like determinants parameterized by a finite number of Baxter's Q-functions. We consider it as a useful step towards the construction of a finite system of non-linear integral equations (FiNLIE) for the full spectrum. The explicit asymptotic form of all the Q-functions for the large size operators is presented. We establish the symmetries and the analyticity properties of the asymptotic Q-functions and discuss their possible generalization to any finite size operators.
