Vacuum replicas in field-theory models of Coulomb QCD

TL;DR

This paper investigates vacuum replica states in a QCD-inspired quark model with a Cornell potential, revealing their stability and meson properties, thus contributing to understanding dynamical symmetry breaking in strong interactions.

Contribution

It introduces and analyzes vacuum replica states in a field-theoretical QCD model with a Cornell potential, showing their stability and meson spectra implications.

Findings

Two excited vacuum-like states are identified.

Replica vacua are classically unstable but stabilized quantum mechanically.

Mesons over these vacua have similar masses to normal mesons.

Abstract

Dynamical symmetry breaking can happen through a Higgs mechanism but also spontaneously within a strongly-enough coupled theory. We treat a field-theoretical quark model of QCD based on a linear+Coulomb Cornell potential (to account for the longitudinal interaction), together with a transverse interaction (to account for Coulomb-gauge gluons) in BCS approximation. After extracting the well-known BCS ground state on which abundant hadron phenomenology implementing dynamical chiral symmetry breaking has been built, we find two excited replica vacuumlike states shown in figure 1. At the BCS level they are classically unstable, but second quantization blocks transitions between them in volumes much larger than a hadron size. Mesons built over the replica vacua have relative masses similar to normal mesons on the ordinary vacuum; we find no negative-mass mode, confirming their stability found earlier with a harmonic oscillator potential.