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arXiv · hep-th/9407125

The Invariant Fermion Correlator in the Schwinger Model on the Torus

James Steele·Jacobus Verbaarschot·Ismail Zahed
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Abstract

We construct the gauge invariant fermion correlator in the Schwinger model on the torus. At zero temperature, this correlator falls off with a rate given by the Coulomb energy of an infinitely heavy charge. At high temperature, the screening mass approaches $πT/2$, and this in the presence of a mass gap. The fractional Matsubara frequency arises from the action of a pair of induced merons at high temperature that are localized over a range on the order of the meson Compton wavelength $1/m=\sqrtπ/g$. We discuss the quenched approximation in this model, and comment on the possible relevance of some of these results to higher dimensions.

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James Steele, Jacobus Verbaarschot, Ismail Zahed. 1994-07-20. The Invariant Fermion Correlator in the Schwinger Model on the Torus. https://doi.org/10.1103/physrevd.51.5915

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