Vector condensation in QCD

TL;DR

This paper investigates how the QCD vacuum responds to high quark chemical potentials, revealing conditions for diquark and vector condensation through chiral perturbation theory.

Contribution

It extends previous work by confirming diquark condensation at next-to-leading order and introduces vector fields to study vector condensation phenomena.

Findings

Diquark condensation occurs when baryon chemical potential exceeds pion mass.

Massless vector modes emerge at the vector mass threshold, indicating possible vector condensation.

Results are confirmed at next-to-leading order in the effective theory.

Abstract

The response of the QCD vacuum to quark chemical potentials on the order of the pion mass is studied within the context of chiral perturbation theory. For two colour QCD diquark condensation sets in when the baryon chemical potential becomes larger than the pion mass. This leading order result is confirmed at next to leading order. Next a set of massive spin-one vectors is included in the effective Lagrangian and the vector masses are calculated at leading order. Massless vector modes appear when the baryon chemical potential is equal to the mass of the lightest vector at zero chemical potential. This suggest vector condensation.