Naturally Light Dirac Neutrinos from $SO(10)\times U(1{)}_{\psi }$

Abstract

A new solution is presented where the right-handed neutrino ${\nu }_R$ in $SO(10)$ pairs up with ${\nu }_L$ to form a naturally light Dirac neutrino. It is based on the framework of $E_6\to SO(10)\times U(1{)}_{\psi }$, then $SO(10)\to SU(5)\times U(1{)}_{\chi }$.

Comments: 9 pages, no figure