- #1

moss

- 49

- 2

(I know the lagrangian and have computed the interaction vertices already) only need to understand the vertex factor.

In other words, I want to learn how 3-boson vertex and 4-boson vertex are computed in Feynman diagrams.

It is, for example, given in Peskin&Schrioeder on page 507 but I don't get it as to what is permuted there, the color indices a,b,c or the lorentz indices and the momentum?

any help/hint is much appricaited !

Thanks.