Structure of Green's Functions in Quantum Field Theory. II

Abstract

In continuation of previous work, it is shown that Green's functions of general order, which involve an arbitrary number of field operators, can be represented as parametric integrals with invariant energy denominators and real spectral functions. The analysis is carried out in detail in the case of neutral scalar fields, but a brief discussion is also made of spinor fields. The (renormalized) equations of motion which give a connection between the Green's functions of different order are converted into the corresponding equations for the spectral functions, which proves that our formulas are consistent and manifestly renormalized, with no infinities inherent in them.