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Observations on staggered fermions at non-zero lattice spacing

Claude Bernard·Maarten Golterman·Yigal Shamir
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Abstract

We show that the use of the fourth-root trick in lattice QCD with staggered fermions corresponds to a non-local theory at non-zero lattice spacing, but argue that the non-local behavior is likely to go away in the continuum limit. We give examples of this non-local behavior in the free theory, and for the case of a fixed topologically non-trivial background gauge field. In both special cases, the non-local behavior indeed disappears in the continuum limit. Our results invalidate a recent claim that at non-zero lattice spacing an additive mass renormalization is needed because of taste-symmetry breaking.

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Claude Bernard, Maarten Golterman, Yigal Shamir. 2006-04-30. Observations on staggered fermions at non-zero lattice spacing. https://doi.org/10.1103/physrevd.73.114511

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