INSTANTON CALCULATIONS VERSUS EXACT RESULTS IN 4 DIMENSIONAL SUSY GAUGE THEORIES.

TL;DR

This paper compares instanton calculations with exact results in 4D supersymmetric gauge theories, using various methods to verify the consistency of non-perturbative effects and explore the limitations of instanton computations at strong coupling.

Contribution

It introduces multiple approaches to relate instanton calculations to exact supersymmetric results, providing detailed numerical checks and highlighting challenges at strong coupling.

Findings

Good agreement between instanton and exact results at weak coupling

Identification of discrepancies at strong coupling

Validation of methods relating strong and weak coupling regimes

Abstract

We relate the non-perturbative exact results in supersymmetry to perturbation theory using several different methods: instanton calculations at weak or strong coupling, a method using gaugino condensation and another method relating strong and weak coupling. This allows many precise numerical checks of the consistency of these methods, especially the amplitude of instanton effects, and of the network of exact solutions in supersymmetry. However, there remain difficulties with the instanton computations at strong coupling.