Infrared divergence of the color-Coulomb self-energy in Coulomb gauge QCD

TL;DR

This study uses lattice simulations to show that the color-Coulomb self-energy in Coulomb gauge QCD diverges in the infrared, indicating confinement persists even above the deconfinement temperature.

Contribution

It provides the first lattice evidence that the color-Coulomb self-energy diverges in both confinement and deconfinement phases in Coulomb gauge QCD.

Findings

Near-zero Faddeev-Popov eigenmodes accumulate at large volumes

Color-Coulomb self-energy diverges in the infrared in both phases

Eigenvalue density behavior is similar in confinement and deconfinement phases

Abstract

We investigate the spectrum of the Faddeev-Popov operator in Coulomb gauge QCD using quenched SU(3) lattice simulation. In the confinement phase, we observe the accumulation of the near-zero modes of the FP operator at large lattice volumes, and the color-Coulomb self-energy diverges in the infrared limit. Moreover, even in the deconfinement phase, the behavior of the FP eigenvalue density is qualitatively the same as in the confinement phase and the color-Coulomb self-energy is infrared divergent.