CP violating phases and a solution to the strong CP problem

Abstract

We present a solution to the strong CP problem based on the identification of the theta angle with twice the CP violating phase present in the CKM quark matrix. This solution washes out all the unwanted issues stemming form the strong CP phase and is strongly justified by general theoretical arguments based on the partition function associated to the $\theta$ vacuum. Phenomenological consequences on the quark mass matrices are discussed for this case.