A phase of confined electroweak force in the early Universe

Abstract

We consider a modified cosmological history in which the presence of beyond-the-Standard-Model physics causes the weak gauge sector, $\mathrm{SU}(2)_L$, to confine before it is Higgsed. Under the assumption of chiral symmetry breaking, quark and lepton weak doublets form condensates that break the global symmetries of the Standard Model, including baryon and lepton number, down to a $\mathrm{U}(1)$ subgroup under which only the weak singlet fermions and Higgs transform. The weakly-coupled gauge group $\mathrm{SU}(3)_c \times \mathrm{U}(1)_Y$ is also broken to an $\mathrm{SU}(2)_c \times \mathrm{U}(1)_Q$ gauge group. The light states include (pseudo-)Goldstone bosons of the global symmetry breaking, mostly-elementary fermions primarily composed of the weak singlet quarks and leptons, and the gauge bosons of the weakly-coupled gauge group. We discuss possible signatures from early Universe cosmology including gravitational wave radiation, topological defects, and baryogenesis.