Critical Behavior in (2+1)-Dimensional QED

Abstract
QED in 2+1 dimensions, analyzed in the 1N expansion, is shown to exhibit a critical behavior as the number N of fermions approaches 32π2. The dynamical mass has a universal scaling behavior at the critical point. The existence of criticality is discovered first by an analytic study of the gap equation and the effective potential. Its existence and universality is then confirmed numerically. Similarities to four-dimensional theories are discussed.