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arXiv · hep-lat/9902007

IR-Divergence and Anomalous Temperature Dependence of the Condensate in the Quenched Schwinger Model

Stephan Dürr·Stephen R. Sharpe
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Abstract

The Schwinger model is used to study the artifacts of quenching in a controlled way. The model is solved on a finite-temperature cylinder of circumference $β=1/T$ with bag-inspired local boundary conditions at the two ends $x^1=0$ and $x^1=L$ which break the $γ_5$-invariance and thus play the role of a small quark mass. The quenched chiral condensate is found to diverge exponentially as $L\to\infty$, and to diverge (rather than melt as for $N_{\rm f}\geq1$) if the high-temperature limit $β\to0$ is taken at finite box-length $L$. We comment on the generalization of our results to the massive quenched theory, arguing that the condensate is finite as $L\to\infty$ and proportional to $1/m$ up to logarithms.

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Stephan Dürr, Stephen R. Sharpe. 2000-05-18. IR-Divergence and Anomalous Temperature Dependence of the Condensate in the Quenched Schwinger Model. https://doi.org/10.1103/physrevd.62.034506

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