A lattice study of the Faddeev-Niemi effective action

TL;DR

This study uses lattice simulations to analyze a generalized Faddeev-Niemi effective action for SU(2) Yang-Mills theory, revealing a mass gap around 1.5 GeV and exploring symmetry breaking effects.

Contribution

It extends the Faddeev-Niemi effective action to include all relevant operators with up to four derivatives and explicit symmetry breaking, providing new insights into the low energy spectrum.

Findings

Mass gap of approximately 1.5 GeV identified

Generalized effective action includes all operators with up to four derivatives

Explicit symmetry breaking terms prevent Goldstone bosons

Abstract

We perform a lattice analysis of the Faddeev-Niemi effective action conjectured to describe the low energy sector of SU(2) Yang-Mills theory. We generalize the effective action such that it contains all operators built from a unit color vector field n with O(3)-symmetry and maximally four derivatives. To avoid the presence of Goldstone bosons, we include explicit symmetry breaking terms parametrized by an external field h of mass-dimension two. We find a mass gap of the order of 1.5 GeV.