Spinor field as elementary excitations of a system of scalar fields

The Dirac field and its quanta are obtained from the imposition of an infinite member of Dirac 2nd class constraints on a system of complex scalar fields having an indefinite internal metric. The spin-1/2 character of the constrained system follows from constraint-induced coupling of the scalar system's independent internal and space-time symmetries, from constraint restrictions on allowed symmetries. The resulting spinor field quanta are seen to exist as a class of "elementary excitations" belonging to a dynamical algebra existing naturally within the system of complex scalar fields.