Fermion universality manifesting itself in the Dirac component of neutrino mass matrix

Abstract

An effective texture is presented for six Majorana conventional neutrinos (three active and three sterile), based on a 6x6 neutrino mixing matrix whose 3x3 active-active component arises from the popular bimaximal mixing matrix of active neutrinos $\nu_e$, $\nu_\mu$, $\nu_\tau$ by three small rotations in the 14, 25, 36 planes of $\nu_1$, $\nu_2$, $\nu_3$ and $\nu_4$, $\nu_5$, $\nu_6$ neutrino mass states. The Dirac component (i.e. 3x3 active-sterile component) of the resulting 6x6 neutrino mass matrix is conjectured to get a structure similar to the charged lepton and quark 3x3 mass matrices, after the bimaximal mixing, specific for neutrinos, is transformed out unitarily {}from the neutrino mass matrix. The charged lepton and quark mass matrices are taken in a universal form constructed previously by the author with a considerable phenomenological success. Then, for the option of $m^2_1\simeq m^2_2\simeq m^2_3\gg m^2_4\simeq m^2_5\simeq m^2_6\simeq0$, the proposed texture {\it predicts} oscillations of solar $\nu_e$'s with $\Delta m^2_{\rm sol}\equiv\Delta m^2_{21}\sim(1.1$ to 1.2)$\times10^{-5}$ eV$^2$, not inconsistent with the LMA solar solution, if the SuperKamiokande value $\Delta m^2_{\rm atm}\equiv\Delta m^2_{32}\sim$(3 to 3.5)$\times10^{-3}$ eV$^2$ for oscillations of atmospheric $\nu_\mu$'s is taken as an input.