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arXiv · hep-lat/9909161

The Phase Diagrams of the Schwinger and Gross-Neveu Models with Wilson Fermions

R. Kenna·C. Pinto·J. C. Sexton
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Abstract

A new method to analytically determine the partition function zeroes of weakly coupled theories on finite-size lattices is developed. Applied to the lattice Schwinger model, this reveals the possible absence of a phase transition at fixed weak coupling. We show how finite-size scaling techniques on small or moderate lattice sizes may mimic the presence of a spurious phase transition. Application of our method to the Gross-Neveu model yields a phase diagram consistent with that coming from a saddle point analysis.

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R. Kenna, C. Pinto, J. C. Sexton. 1999-09-28. The Phase Diagrams of the Schwinger and Gross-Neveu Models with Wilson Fermions. https://doi.org/10.1016/s0920-5632(00)91770-5

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