Neutrinos and Electromagnetic Gauge Invariance
  It is discussed a recently proposed connection among U(1)$_{\rm em}$ electromagnetic gauge invariance and the nature of the neutrino mass terms in the framework of $\mbox {SU(3)}_C\otimes G_W \otimes {\mbox U(1)}_N$, $G_W$ = SU(3)$_L$, extensions of the Standard Model. The impossibility of that connection, also in the extended case $G_W $ = SU(4)$_L$, is demonstrated. 
F. Pisano (IFT - S.Paulo - Brazil), J.A. Silva-Sobrinho (IFT -S.Paulo   - Brazil) and M.D. Tonasse (UERJ - Rio de Janeiro - ...