its complexity, this Lagrangian is best described by breaking it up into several parts as follows.
:

The kinetic term contains all the quadratic terms of the Lagrangian, which include the dynamic terms (the partial derivatives) and the mass terms (conspicuously absent from the Lagrangian before symmetry breaking)
: where the sum runs over all the fermions of the theory (quarks and leptons), and the fields and are given as
: with to be replaced by the relevant field ( ) and by the structure constants of the appropriate