1. Introduction

The self-consistent field theory (SCFT) for many-chain systems is obtained by imposing a mean-field approximation to simplify the statistical field theories. The statistical field theories can be constructed from the particle-based model by carrying out a particle-to-field transformation.

The general approach for a particle-to-field transformation is to invoke formal techniques related to Hubbard-Stratonovich transformations, which have the effect of decoupling interactions among particles (or polymer segments) and replacing them with interactions between the particles and one or more auxiliary fields.

This material is based on the lectures given by Prof. A. C. Shi from Jan. 12 to 14, 2009 at Fudan University, with some additional derivation details.