The nucleon as a topological chiral soliton

We consider a version of the chiral bag model in which the interior quark sector is joined to an exterior meson sector through the requirement of continuity of the axial vector current at the bag surface. The negative energy quark sea plays a crucial role in this model, which reduces to the Skyrme soliton in the limit as the bag radius R→0. The “leakage” of baryon number and energy through the bag results in a remarkable insensitivity of these quantities to the bag radius. Although low-energy phenomenology should display a similar insensitivity, we suggest that a bag radius of 0.44 fm is advantageous on technical grounds. This choice of R should minimize the importance of gluon corrections, vacuum fluctuation effects, and inherent uncertainties in the effective lagrangian.