FERMION MASSES AT STRONG WILSON-YUKAWA COUPLING IN THE SYMMETRICAL PHASE

The fermion mass spectrum is studied in the strong-coupling symmetric (PMS) phase of a scalar-fermion model derived from a lattice proposal of the standard model with Wilson-Yukawa couplings. We find that the fermions are massive and argue for the following interpretation of our numerical results in this PMS phase. The lowest lying fermion spectrum in this phase consists only of a Dirac fermion which is a singlet with respect to the SU(2)L group (the ''neutral'' fermion). We give evidence that the SU(2)L doublet fermion (the ''charged'' fermion), in terms of which the model is originally formulated and which is present in the weak-coupling symmetric phase, is absent in the PMS phase. The neutral fermion is only weakly coupled to the scalar particles and appears to become non-interacting in the scaling region. If this interpretation is correct, the Wilson-Yukawa approach does not lead to a satisfactory lattice formulation of the standard model.