A Dirac-type equation for spacelike neutrinos

Based on experimental evidences supporting the hypothesis that neutrinos might be spacelike particles, a new Dirac-type equation is proposed and a spin-1/2 spacelike quantum theory is developed. The new Dirac-type equation provides a solution for the puzzle of negative mass-square of neutrinos. This equation can be written in two spinor equations coupled together via nonzero mass while respecting maximum parity violation, and it reduces to one Weyl equation in the massless limit. Some peculiar features of spacelike neutrino are discussed in this theoretical framework.