Schwinger model Green functions with topological effects

The fermion propagator and the four-fermion Green function in massless QED(2) are explicitly found with topological effects taken into account. The corrections due to instanton sectors k = +/-1, contributing to the propagator, are shown to be just the homogenous terms admitted by the Dyson-Schwineer equation for S. In the case of the four-fermion function also sectors k= +/-2 are included in the consideration. The quark condensates are then calculated and are shown to satisfy the cluster property. The theta dependence exhibited by the Green functions corresponds to and may be removed by performing certain chiral gauge transformation [S0556-2821(99)02518-7].