Neutral Color Superconductivity and Pseudo-Goldstone Modes

TL;DR

This paper investigates the nature of Goldstone modes in neutral two-flavor color superconductors, revealing that four expected modes are pseudo-Goldstone modes with masses tied to the color chemical potential, impacting our understanding of gauge symmetry breaking.

Contribution

It identifies that four Goldstone modes in neutral two-flavor color superconductors are pseudo-Goldstone modes with masses determined by the color chemical potential, clarifying their physical nature.

Findings

Four Goldstone modes are actually pseudo-Goldstone modes.

Mass of pseudo-Goldstone modes equals the color chemical potential.

Implications for gauge symmetry and neutrality in color superconductors.

Abstract

Four of the five expected Goldstone modes, which will be eaten up by gauge fields, in neutral two-flavor color superconductor are actually pseudo-Goldstone modes, and their degenerated mass is exactly the magnitude of the color chemical potential, which is introduced to guarantee the color neutrality at moderate baryon density.