Comments on fractional instantons in N=2 gauge theories

TL;DR

This paper investigates fractional instantons in N=2 SU(2) gauge theories, presenting new solutions to the Seiberg-Witten problem and showing their role in monopole and dyon condensates, contrasting with gravity dual predictions.

Contribution

It provides new solutions to the Seiberg-Witten monodromy problem and demonstrates fractional instanton effects in N=2 gauge theories from a field theory perspective.

Findings

Fractional instantons contribute to the N=2 prepotential.

New solutions with the same asymptotics as known solutions.

Fractional instantons induce infinite monopole and dyon condensates.

Abstract

N=1^* gauge theories are believed to have fractional instanton contributions in the confining vacua. D3 brane probe computations in gravitation dual of large-N N=2^* gauge theories point to the absence of such contributions in the low energy gauge dynamics. We study fractional instantons in N=2 SU(2) Yang-Mills theory from the field theoretical perspective. We present new solutions to the Seiberg-Witten SU(2) monodromy problem with the same perturbative asymptotic, a massless monopole and a dyon singularity on the moduli space, and fractional instanton corrections to N=2 prepotential in the semi-classical region of the moduli space. We show that fractional instantons lead to infinite monopole (dyon) condensate in mass deformed N=2 gauge theories.