Two-dimensional field theory with several condensed phases

The effective-action method is used to study a two-dimensional theory with four-fermion current-current interaction. A phase transition with respect to the coupling constant from the symmetric to nonsymmetric phase is found. In the different phases, there exist different numbers of Goldstone modes of the Bose excitations as in the anisotropic superfluid phases of ${}^3\operatorname{He}$.