A simple scheme for masses and mixings of quarks and neutrinos

TL;DR

This paper proposes a simple, unified structure for fermion mass matrices using a small parameter, leading to predictions about neutrino masses and mixings consistent with observed phenomena.

Contribution

It introduces a unified approach to fermion masses and neutrino mixing matrices using a common parameter, with implications for neutrino oscillation solutions.

Findings

Heavy neutrino mass matrix expressed in terms of sigma

Tiny mass splitting for light neutrinos favors vacuum oscillation

Mixing matrix is bimaximal with CP phases

Abstract

The mass matrices of charged fermions have a simple structure if expressed in powers of the small parameter sigma=(m_c/m_t)^{1/2}. It is suggested that the mass matrix of the three heavy neutrinos occuring in grand unified theories can be expressed in terms of the same parameter. The requirement that these heavy neutrinos carry different U(1) generation quantum numbers gives rise to an almost unique form for this matrix. By applying the see-saw mechanism, the mass splitting of the two lightest neutrinos comes out to be tiny, favoring the vacuum oscillation solution for solar neutrinos. The mixing matrix is of the bimaximal type but contains also CP violating phases.