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Staggered eigenvalue mimicry

Stephan Dürr·Christian Hoelbling·Urs Wenger
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Abstract

We study the infrared part of the spectrum for UV-filtered staggered Dirac operators and compare them to the overlap counterpart. With sufficient filtering and at small enough lattice spacing the staggered spectra manage to ``mimic'' the overlap version. They show a 4-fold near-degeneracy, and a clear separation between would-be zero modes and non-zero modes. This suggests an approximate index theorem for filtered staggered fermions and a correct sensitivity to the topology of QCD. Moreover, it supports square-rooting the staggered determinant to obtain dynamical ensembles with $N_f=2$.

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BibTeXRIS

Stephan Dürr, Christian Hoelbling, Urs Wenger. 2004-09-20. Staggered eigenvalue mimicry. https://doi.org/10.1103/physrevd.70.094502

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