Universal Democracy Instead of Anarchy

Abstract

We propose for the flavour structure of both the quark and lepton sectors, the principle of Universal Democracy (UD), which reflects the presence of a $Z_3$ symmetry. In the quark sector, we emphasize the importance of UD for obtaining small mixing and flavour alignment, while in the lepton sector, large mixing, including the recently measured value of $U_{e3}$, is obtained in the UD framework through the seesaw mechanism. An interesting correlation between the values of $U_{e3}$ and $\sin^2(\theta_{23})$ is pointed out, with the prediction of $\sin^2(\theta_{23})\approx 0.42$ in the region where $U_{e3}$ is in agreement with the DAYA-BAY experiment.