We investigate spectral functions extracted using the Maximum Entropy Method
from correlators measured in lattice simulations of the (2+1)-dimensional
four-fermion model. This model is particularly interesting because it has both
a chirally broken phase with a rich spectrum of mesonic bound states and a
symmetric phase where there are only resonances. In the broken phase we study
the elementary fermion, pion, sigma and massive pseudoscalar meson; our results
confirm the Goldstone nature of the pi and permit an estimate of the meson
binding energy. We have, however, seen no signal of sigma -> pi pi decay as the
chiral limit is approached. In the symmetric phase we observe a resonance of
non-zero width in qualitative agreement with analytic expectations; in addition
the ultra-violet behaviour of the spectral functions is consistent with the
large non-perturbative anomalous dimension for fermion composite operators
expected in this model.Comment: 25 pages, 13 figure
