A Second Higgs Doublet in the Early Universe: Baryogenesis and Gravitational Waves

TL;DR

This paper demonstrates that Two Higgs Doublet models can explain the matter-antimatter asymmetry through electroweak baryogenesis and predict gravitational waves detectable by LISA.

Contribution

It shows that simple Two Higgs Doublet models remain viable for baryogenesis and predicts observable gravitational waves within current experimental constraints.

Findings

Electroweak baryogenesis is viable in these models.

Predicted gravitational wave spectrum is within LISA's sensitivity.

Models are consistent with recent electron-EDM bounds.

Abstract

We show that simple Two Higgs Doublet models still provide a viable explanation for the matter-antimatter asymmetry of the Universe via electroweak baryogenesis, even after taking into account the recent order-of-magnitude improvement on the electron-EDM experimental bound by the ACME Collaboration. Moreover we show that, in the region of parameter space where baryogenesis is possible, the gravitational wave spectrum generated at the end of the electroweak phase transition is within the sensitivity reach of the future space-based interferometer LISA.