Baryogenesis in a parity solution to the strong CP problem.

Space-time parity can solve the strong CP problem and introduces a spontaneously broken SU(2)_R gauge symmetry. We investigate the possibility of baryogenesis from a first-order SU(2)_R phase transition similar to electroweak baryogenesis. We consider a model with the minimal Higgs content, for which the strong CP problem is indeed solved without introducing extra symmetry beyond parity. Although the parity symmetry seems to forbid the SU(2)_R anomaly of the B − L symmetry, the structure of the fermion masses can allow for the SU(2)_R sphaleron process to produce non-zero B − L asymmetry of Standard Model particles so that the wash out by the SU(2)_L sphaleron process is avoided. The setup predicts a new hyper-charged fermion whose mass is correlated with the SU(2)_R symmetry breaking scale and hence with the SU(2)_R gauge boson mass, and depending on the origin of CP violation, with an electron electric dipole moment. In a setup where CP violation and the first-order phase transition are assisted by a singlet scalar field, the singlet can be searched for at future colliders. [ABSTRACT FROM AUTHOR]