interactions. The interactions are long range, cannot be screened, and result in anomalies in
perturbation theory. In the Hartree-Fock theory, we find an instability of the Landau Fermi-
liquid state resulting in ''fermion-condensate''states with a high degeneracy of levels at the
Fermi energy. This degeneracy may be removed to give a Fermi-liquid state with vanishing
Fermi velocity. As an example, we investigate further the Fermi-liquid state with the …