Dielectric function of the QCD vacuum

TL;DR

This paper demonstrates that the inverse ghost form factor acts as the color dielectric function of the QCD vacuum, revealing its dual superconductor nature in the infrared regime through a variational approach.

Contribution

It introduces a novel interpretation of the ghost form factor as the QCD vacuum's dielectric function and explicitly calculates it using a variational method.

Findings

QCD vacuum behaves as a perfect color diaelectric medium in the infrared

The inverse ghost form factor is identified as the dielectric function

The vacuum exhibits dual superconductor characteristics

Abstract

It is shown that the inverse of the ghost form factor in the Hamilton approach to Yang-Mills theory in Coulomb gauge can be interpreted as the color dielectric function of the QCD vacuum. Furthermore the horizon condition to the ghost form factor implies that in the infrared the QCD vacuum is a perfect color diaelectric medium and therefore a dual superconductor. The dielectric function is explicitly calculated within a previously developed variational approach, using a specific ansatz for the vacuum wave functional.