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arXiv · hep-lat/0506027

Filtered overlap: speedup, locality, kernel non-normality and Z_A~1

Stephan Durr·Christian Hoelbling·Urs Wenger
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Abstract

We investigate the overlap operator with a UV filtered Wilson kernel. The filtering leads to a better localization of the operator even on coarse lattices and with the untuned choice $ρ=1$. Furthermore, the axial-vector renormalization constant $Z_A$ is much closer to 1, reducing the mismatch with perturbation theory. We show that all these features persist over a wide range of couplings and that the details of filtering prove immaterial. We investigate the properties of the kernel spectrum and find that the kernel non-normality is reduced. As a side effect we observe that for certain applications of the filtered overlap a speed-up factor of 2-4 can be achieved.

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Stephan Durr, Christian Hoelbling, Urs Wenger. 2005-06-28. Filtered overlap: speedup, locality, kernel non-normality and Z_A~1. https://doi.org/10.1088/1126-6708%2F2005%2F09%2F030

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