Pion Configurations in the Presence of Baryons
  In the framework of chiral perturbation theory we investigate whether, in the presence of nucleons, a many-particle system may lower its energy density by changing its mesonic vacuum from a homogeneous to a spiral configuration. Numerical values for the critical particle number densities for the spiral configuration to occur are given. They lie in the region of nuclear matter density where the applicability of chiral perturbation theory should be checked carefully. 
Daniel Arnold
hep-ph