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arXiv · hep-lat/0512021

Stability of lattice QCD simulations and the thermodynamic limit

L. Del Debbio·L. Giusti·M. Lüscher·R. Petronzio·N. Tantalo
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Abstract

We study the spectral gap of the Wilson--Dirac operator in two-flavour lattice QCD as a function of the lattice spacing $a$, the space-time volume $V$ and the current-quark mass $m$. It turns out that the median of the probability distribution of the gap scales proportionally to $m$ and that its width is practically equal to $a/\sqrt{V}$. In particular, numerical simulations are safe from accidental zero modes in the large-volume regime of QCD.

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L. Del Debbio, L. Giusti, M. Lüscher, R. Petronzio, N. Tantalo. 2005-12-15. Stability of lattice QCD simulations and the thermodynamic limit. https://doi.org/10.1088/1126-6708%2F2006%2F02%2F011

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