Chiral symmetry restoration in the CPn-12 model with fermions

The large n limit of the CP^n-1₂ model with fermions carrying a U(N) × U(N) chiral symmetry predicts (apparent) spontaneous chiral symmetry breaking. As a consequence there are N² - 1 Goldstone bosons left over from the symmetry breaking. This is in contradiction with Coleman's theorem. We show that the symmetry is restored in a way analogous to the ``Berezinski-Kosterlitz-Thouless phase'' for the X - Y model. The resolution of the U(1) problem in this model is unaffected by our results.

Present address: Theory Division, CERN, Geneva, Switserland.