Regge meets collinear in strongly-coupled $\mathcal{N} = 4$ super Yang-Mills

TL;DR

This paper analyzes the six-gluon remainder function in planar $ abla=4$ super Yang-Mills theory at strong coupling, revealing new subleading terms and establishing a precise correspondence between different formalisms, with implications for higher-point amplitudes.

Contribution

It identifies an infinite set of subleading terms in the strong coupling limit and maps the TBA results to the Wilson loop OPE formalism, extending to seven-gluon amplitudes.

Findings

New subleading terms in the multi-Regge limit at strong coupling

Exact mapping between TBA and Wilson loop OPE formalisms

Non-trivial behavior of the central emission vertex at strong coupling

Abstract

We revisit the calculation of the six-gluon remainder function in planar $\mathcal{N} = 4$ super Yang-Mills theory from the strong coupling TBA in the multi-Regge limit and identify an infinite set of kinematically subleading terms. These new terms can be compared to the strong coupling limit of the finite-coupling expressions for the impact factor and the BFKL eigenvalue proposed by Basso et al. in arXiv:1407.3766, which were obtained from an analytic continuation of the Wilson loop OPE. After comparing the results order by order in those subleading terms, we show that it is possible to precisely map both formalisms onto each other. A similar calculation can be carried out for the seven-gluon amplitude, the result of which shows that the central emission vertex does not become trivial at strong coupling.