We suggest a simple highly predictive ansatz for charged lepton and light neutrino mass matrices, based on the assumption of universality of Yukawa couplings. Using as input the charged lepton masses and light neutrino masses, the six parameters characterizing the leptonic mixing matrix $V_{\mathrm{PMNS}}$ are predicted in terms of a single phase $\varphi$, which takes a value around $\varphi =\frac{\pi }{2}$. Correlations among various physical quantities are obtained; in particular $V_{13}^{\mathrm{PMNS}}$ is predicted as a function of $\Delta m_{21}^2$, $\Delta m_{31}^2$, and ${sin}^2({\theta }_{\mathrm{sol}})$, and restricted to the range $0.167<|V_{13}^{\mathrm{PMNS}}|<0.179$.

• Received 9 September 2009

DOI:https://doi.org/10.1103/PhysRevD.80.073016