QCD at largeNc—Skyrme or the bag?

Abstract

A framework for extracting the low-energy dynamics of pseudoscalar mesons from QCD at large N is developed and, to leading order in the decoupling of heavy mesons, the pure pseudoscalar theory is calculated truncated to four derivatives. The soliton is found not to be manifestly stabilized by the four derivative terms. Under a plausible assumption about the classical solution for the scalar meson field, a natural realization of the previously proposed topological soliton bag model is obtained.