Schwinger Model Green functions with topological effects
نویسنده
چکیده
The fermion propagator and the 4-fermion Green function in the massless QED2 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-Schwinger equation for S. In the case of the 4-fermion function also sectors k = ±2 are included into consideration. The quark condensates are then calculated and are shown to satisfy cluster property. The θ-dependence exhibited by the Green functions corresponds to and may be removed by performing certain chiral gauge transformation. 11.10.-z;11.30.Rd;12.90.+b Typeset using REVTEX ∗Elecronic mail: [email protected]
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