# Canonical momentum for Dirac adjoint field

1. Nov 24, 2015

### nigelscott

I read that the canonical momentum for Dirac adjoint field is zero. Why is that?

2. Nov 24, 2015

### haushofer

What does your calculation give you?

3. Nov 24, 2015

### dextercioby

You should be using the symmetrized „classical” action:

4. Nov 24, 2015

### nigelscott

I know that π = iψbarγ0. My confusion concerns the notion of the derivative in the Lagrangian 'acting to the right' for ψ or 'acting to the left' for ψbarγ0 . If I ignore that confusion then I can see that the canonical momentum would be 0.

5. Nov 24, 2015

### nigelscott

should be 'acting to the left' for ψbar