Connection Between the Neutrino Seesaw Mechanism and Properties of the   Majorana Neutrino Mass Matrix
  If it can be ascertained experimentally that the 3X3 Majorana neutrino mass matrix M_nu has vanishing determinants for one or more of its 2X2 submatrices, it may be interpreted as supporting evidence for the theoretically well-known canonical seesaw mechanism. I show how these two things are connected and offer a realistic M_nu with two zero subdeterminants as an example. 
Ernest Ma (UC Riverside)