We use the O(N) model as a nonperturbative example to study the effect of truncating the Schwinger-Dyson sequence of equations. We show that truncation of this hierarchy leads in the O(N) model to solutions for the propagators and vertex functions correct to a definite power of 1N. The procedure can be used to generate a systematic expansion in 1N for an arbitrary Green's function of the model.
ASJC Scopus subject areas
- Nuclear and High Energy Physics
- Physics and Astronomy (miscellaneous)