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The Absence of Ultralocal Ginsparg-Wilson Fermions

W. Bietenholz
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Abstract

It was shown recently by I. Horvath that lattice fermions obeying the standard form of the Ginsparg-Wilson relation cannot be ultralocal. However, there are more general forms of the Ginsparg-Wilson relation, which also guarantee the physical properties related to chirality, but which are not covered by Horvath's consideration. Here we present a proof which applies to all Ginsparg-Wilson fermions, demonstrating that they can only be local in the sense of an exponential decay of their couplings, but not ultralocal.

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W. Bietenholz. 2000-02-24. The Absence of Ultralocal Ginsparg-Wilson Fermions. https://arxiv.org/abs/hep-lat/9901005

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