Intersecting Surface Defects and Instanton Partition Functions

TL;DR

This paper computes the instanton partition functions in 4d N=2 theories with intersecting surface defects by analyzing RG flows from larger theories and formulating the problem as coupled 4d/2d/0d systems.

Contribution

It introduces a method to calculate instanton partition functions with intersecting defects using RG flow and coupled system frameworks, providing explicit formulas.

Findings

Explicit expressions for instanton partition functions with intersecting defects

Analysis of the ADHM model in the presence of intersecting surface defects

Framework connecting RG flows to defect-influenced partition functions

Abstract

We analyze intersecting surface defects inserted in interacting four-dimensional N = 2 supersymmetric quantum field theories. We employ the realization of a class of such systems as the infrared fixed points of renormalization group flows from larger theories, triggered by perturbed Seiberg-Witten monopole-like configurations, to compute their partition functions. These results are cast into the form of a partition function of 4d/2d/0d coupled systems. Our computations provide concrete expressions for the instanton partition function in the presence of intersecting defects and we study the corresponding ADHM model.