Intermediate Volumes and the Role of Instantons

TL;DR

This paper reviews recent findings on the low-lying glueball spectrum in intermediate volumes, emphasizing the importance of instanton effects and non-perturbative corrections implemented via boundary conditions.

Contribution

It introduces a novel approach to incorporate instanton effects through boundary conditions on the gauge field's fundamental domain.

Findings

Instanton effects significantly influence the glueball spectrum.

Non-perturbative boundary conditions are crucial for accurate results.

The method improves understanding of gauge theories in finite volumes.

Abstract

We review recent results for the low-lying glueball spectrum on the three-sphere in intermediate volumes that incorporate instanton effects. The latter are implemented through boundary conditions on the fundamental domain obtained by minimising the norm of the gauge field along the gauge orbit. Non-perturbative corrections due to the boundary conditions in field space are seen to be crucial.