Microscopic- versus Effective Coupling in N=2 Yang-Mills With Four Flavours

TL;DR

This paper calculates all-order instanton corrections to the effective coupling in SU(2), N=2 Yang-Mills theory with four flavors, using S(2,Z) symmetry and previous two-instanton data.

Contribution

It provides a complete determination of instanton corrections to the effective coupling in this theory, leveraging symmetry and earlier partial results.

Findings

All-order instanton corrections explicitly determined.

Utilizes S(2,Z) invariance to fix higher-order terms.

Builds on previous two-instanton calculations.

Abstract

We determine the instanton corrections to the effective coupling in SU(2), N=2 Yang-Mills theory with four flavours to all orders. Our analysis uses the S(2,Z)-invariant curve and the two instanton contribution obtained earlier to fix the higher order contributions uniquely.