Neutrino Mass Seesaw Version 3: Recent Developments

Abstract

The origin of neutrino mass is usually attributed to a seesaw mechanism, either through a heavy Majorana fermion singlet (version 1) or a heavy scalar triplet (version 2). Recently, the idea of using a heavy Majorana fermion triplet (version 3) has gained some attention. This is a review of the basic idea involved, its U(1) gauge extension, and some recent developments.

Comments: 8 pages, 4 figures, talk at XIII Mexican School of Particles and Fields, San Carlos, Sonora, Mexico, Oct 2008