Analytical and numerical routes to strong coupling in $\mathcal{N}=2$ SCFTs

TL;DR

This paper develops analytical and numerical methods to analyze strong coupling regimes in certain $ ext{N}=2$ superconformal field theories, focusing on Wilson loop correlators and Higgs branch operator correlators.

Contribution

It introduces an analytic approach for initial strong coupling expansion terms and a numerical algorithm for independent verification and exploration of observables beyond current analytical reach.

Findings

Analytic expressions for strong coupling expansion terms of selected observables.

Numerical algorithm providing independent checks and predictions.

Enhanced understanding of non-closed-form observables at strong coupling.

Abstract

We consider the $\mathcal{N}=2$ quiver gauge theory arising from a $\mathbb{Z}_M$ orbifold of $\mathcal{N}=4$ Super Yang-Mills theory. Over the years, exploiting supersymmetric localization, exact expressions for several observables have been derived in the planar limit of this theory. In particular, some of these can be expressed as Fredholm determinants of semi-infinite matrices and their strong coupling expansions in inverse powers of the 't Hooft coupling have been calculated analytically to any desired order. On the other hand, there are also observables that cannot be rewritten in such a closed form, therefore extracting information at strong coupling is more complicated and almost no results are known beyond the leading order. In this work we focus on two observables of this type: the correlators of $n$ coincident Wilson loops and the integrated correlators of two Higgs branch operators in the presence of a Wilson line. We introduce an analytic method to evaluate the first terms of their strong coupling expansions. We also outline a numerical algorithm that serves as an independent check of the analytical results and provides predictions in cases where analytical techniques are currently not known.