The chiral bag

In this Comment, we review the present status of the chiral bag as a possibly realistic candidate model of low-energy quantum chromodynamics, particularly suited to nuclear dynamics, possessing the unique virtue of interpolating between the long-distance Goldstone-mode regime and the short-distance asymptotically free regime. Being the only four-dimensional topological soliton observed so far in nature, the nucleon as described in the model offers a valuable laboratory to study the intricate way the topology enters into physics. (author)