Electroweak symmetry non-restoration and suppressed dark radiation in Supersymmetric Twin Higgs model

TL;DR

This paper explores electroweak symmetry non-restoration in a supersymmetric Twin Higgs model, showing it can lead to a first-order phase transition and reduce dark radiation, aligning with cosmological observations and offering insights into baryogenesis and dark matter.

Contribution

It introduces a supersymmetric Twin Higgs framework with light scalars that enables electroweak symmetry non-restoration and connects it to dark radiation suppression and baryogenesis.

Findings

Electroweak symmetry non-restoration can occur below the TeV scale.

Light scalars stabilize the electroweak scale and enable a first-order phase transition.

Dark radiation can be suppressed to levels consistent with CMB constraints.

Abstract

We investigate a possibility of electroweak symmetry non-restoration (SNR) below the Twin electroweak scale ($\sim$TeV) within the Twin Higgs model. We focus on supersymmetric extensions with light sfermions where SNR is driven by mirror symmetry breaking in the Yukawa couplings. The inclusion of light scalars not only stabilizes the electroweak scale, but also extends SNR into new regions of the parameter space and enables a first-order phase transition. When this model is augmented with right-handed neutrinos with unbroken $B'-L'$ in the twin sector, the number of dark relativistic degrees of freedom can be reduced to the level consistent with the constraints from CMB data. The SNR in the supersymmetric Twin Higgs framework can naturally be integrated with minimal axiogenesis, offering a simultaneous explanation for the origin of baryon asymmetry and dark matter and the resolution of the strong CP problem that is consistent with astrophysical constraints.