and many others. Therefore it would be very interesting to have some model independent framework to make a phenomenological description of the $ESB$ physics.

In fact such a framework exists, at least for the strongly interacting case i.e., when no light modes are present in the $ESB$. It has been developed in the last years and used to describe the scattering of the longitudinal components ($LC$) of the electroweak gauge bosons [@HeE1] as well as the precision tests of the Standard Model coming from $LEP$ [@HeE2]. It is based on the application of the chiral Lagrangians or Chiral Perturbation Theory ($\chi PT$ )[@Wleff] (previously invented for the description of the low-energy hadron interactions) to the dynamics of the $ESB$ Goldstone bosons ($GB$).

One assumes that there is a physical system with a global symmetry group $G$ which is spontaneously broken to some other group $H$. This global symmetry breaking drives the gauge electroweak $SU(2)_L \times U(1)_Y$ symmetry breaking down to $U(1)_{em}$ through the well known Higgs mechanism. The only election for the $G$ and $H$ groups compatible with the presence of the $SU(2)_{L+R}$ custodial symmetry [@cus] (to have a $\rho$ parameter naturally close to one) and the existence of three 