Isotopic symmetry: weak interactions in the nonlinear realization scheme

Gauge models of lepton and hadron weak interactions are discussed in the framework of nonlinear-realized isotopic symmetry. Massless vector field inclusion into the nonlinear theory leads to a special gauging, to complete disappearance of scalar mesons from the Lagrangian, and to the appearance of masses in vector fields. No higgs scalars appear. Another characteristics property-randomness in a vector field mass spectrum-enables to discuss a version of Weak interaction with light intermediate bosons. Both these properties account for the nonlinear scheme that offers a less number of algebraic consequences than the linear one. However, the condition under which asymptotic behaviour of the amplitude ''tree'' of fermien-antifermien pair annihilation into longitudinally poluarized vector meson pairs should not violate the unitary limit leads to the algebraic realization of symmetry, i.e. to the appearance of the isomultiplet structure of fermiens with a given helicity value