Monopole condensation and the dynamics of chiral symmetry breaking in non-compact lattice QED with dynamical fermions

We study the interplay of chiral symmetry breaking, strong vector forces, monopole condensation and four Fermi interactions in non-compact lattice quantum electrodynamics (QED) with Nf species of almost massless fermions. For Nf=2 and 4 simulations on 104 and 164 lattices show that the chiral symmetry breaking transition is coincident with monopole condensation. This result implies that lattice non-compact QED in its current implementation cannot be used to study the properties of conventional continuum QED at strong bare couplings, but may be relevant to grand unification schemes containing abelian gauge sectors with monopoles. We present measurements of finite size scaling of the monopole susceptibility and the chrial equation of state. (orig.)