We discuss the possibility of generating a light composite scalar boson, in a
scenario that we may generically call Technicolor, or in any variation of a
strongly interacting theory, where by light we mean a scalar composite mass
about one order of magnitude below the characteristic scale of the strong
theory. Instead of most of the studies about a composite Higgs boson, which are
based on effective Lagrangians, we consider this problem in the framework of
non-perturbative solutions of the fermionic Schwinger-Dyson and Bethe-Salpeter
equations. We study a range of mechanisms proposed during the recent years to
form such light composite boson, and verify that such possibility seems to be
necessarily associated to a fermionic self-energy that decreases slowly with
the momentum.Comment: 35 pages, 6 figures, few typos corrected. Version to appear in IJMP
