# Why does the majorana equation preserve handedness?

In the "QFT Nutshell" by A. Zee, it is stated that

The Majorana equation is $$i\not\partial\psi=m\psi_c$$ where $$\psi_c$$ is the charge conjugated spinor $$\psi_c = \left(C\gamma^0\right)\psi^*$$. As $$\psi_c$$ is right handed if $$\psi$$ is left handed, the Majorana equation, unlike the Dirac equation, preserves handedness.

I have completely no idea what the author means when he says "the equation preserves handedness".

• Do you appreciate handedness (chirality) and how the massive Dirac's equation violates it? (connects left- to right-handers). – Cosmas Zachos Aug 6 at 0:43
• I think understand the chirality. It is how the spin of the particle relates to its direction of motion. I am not really sure how the massive Dirac's equation violates the chirality. But if I were to guess, I would say that by looking at the Dirac's Lagrangian, the mass terms connect the left handed spinor to the right handed spinor. Is that the correct way to see? – TangBear Aug 6 at 9:17
• You are close, but you are confusing helicity with chirality, which makes all the difference: for Tony, "handedness" is chirality! Go to a world without right-chiral particles. Note that you cannot write a massive Dirac equation there, but you can a Majorana equation. – Cosmas Zachos Aug 6 at 13:34
• I think I understand now. Thank you very much! – TangBear Aug 6 at 15:37