Computer simulation of chiral-symmetry breaking in (2+1)-dimensional QED with N flavors

Noncompact quantum electrodynamics in three Euclidean dimensions with N species of four-component Dirac fermions is simulated by lattice-gauge-theory techniques. On an $8^3$ lattice we find chiral-symmetry breaking in the continuum limit for N≤$N_c$ but no symmetry breaking for N≥$N_c$, with $N_c$=3.5±0.5. A physical picture of our results is presented.