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The Phase Structure of the Schwinger Model on the Lattice with Wilson Fermions in the Hartree-Fock Approximation

Ivan Horvath
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Abstract

The phase diagram of the Schwinger model on the lattice with one and two degenerate flavours of Wilson fermions is investigated in the Hartree-Fock approximation. In case of a single flavour (not directly amenable to numerical simulation), the calculation indicates the existence of the parity violating phase at both weak and intermediate-to-strong couplings. In the broken phase, the Hartree-Fock vacuum sustains a nonzero electric field. With two flavours, parity is not broken at weak coupling. However, both parity and flavour become spontaneously broken at the Hartree-Fock level as the coupling becomes strong.

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Ivan Horvath. 1995-10-09. The Phase Structure of the Schwinger Model on the Lattice with Wilson Fermions in the Hartree-Fock Approximation. https://doi.org/10.1103/physrevd.53.3808

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