Axionless solution to strong CP problem

by Stefano Morisi (Università federico II Napoli)

Tuesday 21 Jul 2026, 14:00 → 15:30 Europe/Rome

Aula Seminari (Laboratori Nazionali di Frascati)

I propose two alternatives to the axion mechanism for addressing the strong CP problem.  The first approach involves imposing CP as an inherent symmetry of the Lagrangian, which is then spontaneously broken. To generate the correct texture for the Yukawa matrices, is assumed a discrete Z2 symmetry that is softly broken by the scalar potential. By identifying a benchmark point for the Yukawa couplings that aligns with the measured quark masses, the CKM matrix, and low-energy flavor-changing constraints, our findings suggest that this model offers a viable solution to the CP problem I also mention a second approach based on SO(10) GUT model.