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arXiv · hep-lat/9812016

The Schwinger Model with Perfect Staggered Fermions

W. Bietenholz·H. Dilger
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Abstract

We construct and test a quasi-perfect lattice action for staggered fermions. The construction starts from free fermions, where we suggest a new blocking scheme, which leads to excellent locality of the perfect action. An adequate truncation preserves a high quality of the free action. An Abelian gauge field is inserted in d=2 by effectively tuning the couplings to a few short-ranged lattice paths, based on the behavior of topological zero modes. We simulate the Schwinger model with this action, applying a new variant of Hybrid Monte Carlo, which damps the computational overhead due to the non-standard couplings. We obtain a tiny ``pion'' mass down to very small β, while the ``η'' mass follows very closely the prediction of asymptotic scaling. The observation that even short-ranged quasi-perfect actions can yield strong improvement is most relevant in view of QCD.

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BibTeXRIS

W. Bietenholz, H. Dilger. 1998-12-18. The Schwinger Model with Perfect Staggered Fermions. https://doi.org/10.1016/s0550-3213(99)00113-3

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