Consider a U(1) symmetry of a complex scalar field realized as ϕ→ϕ′=eiQθϕ.
where Q is the generator of the symmetry. The conserved Noether's charge (in D-spatial dimensions) corresponding to this symmetry is given by QN=∫j0(x,t)dDx=iQ∫dDx[(∂0ϕ)ϕ∗−(∂0ϕ∗)ϕ].
So it turns out that QN∝Q but not equal to Q itself.
But in A. Zee's book QFT in a Nutshell, page 198, the Noether charge corresponding to a symmetry U(θ)=eiQθ
is written as QN=∫j0(x,t)dDx=Q
But as I've shown QN∝Q. So is it a mistake there? Or am I missing something?
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