Infrared cutoff dependence of the critical flavor number in three-dimensional QED

Abstract

We solve, analytically and numerically, a gap equation in parity invariant QED_3 in the presence of an infrared cutoff μand derive an expression for the critical fermion number N_c as a function of μ. We argue that this dependence of N_c on the infrared scale might solve the discrepancy between continuum Schwinger-Dyson equations studies and lattice simulations of QED_3.

5 pages, 1 figure (revtex4), final version