My question is only a formal comparison between the two currents: the presence of a derivative term in one case and its absence in the other intrigues me (although its demonstration from the Lagrangian is straightforward). But perhaps there is no lesson to be learned.
For a complex scalar field, the lagrangian density and the associated conserved current are given by:
$$ \mathcal{L} = \partial^\mu \psi^\dagger \partial_\mu \psi -m^2 \psi^\dagger \psi $$
$$J^{\mu} = i \left[ (\partial^\mu \psi^\dagger ) \psi - (\partial^\mu \psi ) \psi^\dagger \right] $$...
Actually, I'm looking for a reference for this graph: https://en.wikipedia.org/wiki/Mathematical_formulation_of_the_Standard_Model#/media/File:Standard_Model.svg
I'm new to this and want to make sure I understand: do the letters L and R for particles refer to chirality, not helicity ? The...
I'm making one last attempt about this graph. I looked for it in some QFT books and didn't see it.
Does anyone have a reference, either an academic book or a review article that shows this graph, instead of this wiki page ?
Thanks for your answer.
Since the coupling constant for the weak hypercharge is given by g' cos (theta_w) = e, I naively thought that the weak hypercharge Yw was related to the electric charge Q in the same way by Yw cos(theta_w) = Q. What puzzles me is the fact that the particle graph seems...
The graphical pattern of particles in the weak hypercharge and weak isospin plane, visible in this wiki page, shows the mixing angle between the Yw and Q axes. Actually , from the weak hypercharge (-2) of a right-handed electron and its electric charge (-1), one obtains an angle Pi/3, not the...