Seesaw mechanism
= Seesaw mechanism
{wiki}
The type-I <seesaw mechanism> combines a <Dirac neutrino> <mass> $m_D$ with a much larger right-handed-neutrino <Majorana mass term> $M$. Diagonalizing the <mass> matrix gives a light <eigenvalue> of order $m_D^2/M$ and a heavy <eigenvalue> of order $M$.