Color Breaking in the Early Universe

TL;DR

This paper investigates the possibility of spontaneous color symmetry breaking in the early universe through minimal extensions of the standard model, revealing phases where color is broken and restored at different temperatures.

Contribution

It proposes a novel scenario where color symmetry is spontaneously broken at certain early universe temperatures using minimal scalar extensions, and analyzes its consistency with collider bounds.

Findings

Color symmetry can be spontaneously broken at intermediate temperatures.

Color symmetry is restored at very high and low temperatures.

Breaking of color is linked with B-L symmetry breaking under certain conditions.

Abstract

We explore the possibility that color symmetry SU(3) was not an exact symmetry at all times in the early universe, using minimal extensions of the standard model that contain a color triplet scalar field and perhaps other fields. We show that, for a range of temperatures, there can exist a phase in which the free energy is minimized when the color triplet scalar has a non-vanishing vacuum expectation value, spontaneously breaking color. At very high temperatures and at lower temperatures color symmetry is restored. The breaking of color in this phase is accompanied by the spontaneous breaking of B-L if the color triplet scalar Yukawa couples to quarks and/or leptons. We discuss the requirements on the minimal extensions needed for consistency of this scenario with present collider bounds on new colored scalar particles.