Self-consistent dynamics of a light composite scalar Higgs boson

We apply a simple approximate relativistic amplitude-unitarization generalization of nonrelativistic Schrödinger-equation dynamics to the scattering of longitudinal mass-degenerate W and Z gauge bosons. The strong energy dependence of our amplitude near the WW threshold then makes possible a nonperturbative self-consistent nonelementary neutral Higgs scalar bound state (H) just below this threshold. We must, however, include a constant term approximating high-energy inelastic effects in addition to H exchange. Everything, including the H mass, can then be determined in terms of the small phenomenological WWH coupling and W mass, which serves to set the energy scale of the problem; this is the same number of arbitrary parameters as in the underlying electroweak theory.