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arXiv · hep-lat/0306022

Spectral Properties of the Overlap Dirac Operator in QCD

W. Bietenholz·K. Jansen·S. Shcheredin
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Abstract

We discuss the eigenvalue distribution of the overlap Dirac operator in quenched QCD on lattices of size 8^{4}, 10^{4} and 12^{4} at β= 5.85 and β= 6. We distinguish the topological sectors and study the distributions of the leading non-zero eigenvalues, which are stereographically mapped onto the imaginary axis. Thus they can be compared to the predictions of random matrix theory applied to the ε-expansion of chiral perturbation theory. We find a satisfactory agreement, if the physical volume exceeds about (1.2 fm)^{4}. For the unfolded level spacing distribution we find an accurate agreement with the random matrix conjecture on all volumes that we considered.

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W. Bietenholz, K. Jansen, S. Shcheredin. 2003-09-25. Spectral Properties of the Overlap Dirac Operator in QCD. https://doi.org/10.1088/1126-6708%2F2003%2F07%2F033

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