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An alternative to domain wall fermions

R. Narayanan·H. Neuberger
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Abstract

We define a sparse hermitian lattice Dirac matrix, $H$, coupling $2n+1$ Dirac fermions. When $2n$ fermions are integrated out the induced action for the last fermion is a rational approximation to the hermitian overlap Dirac operator. We provide rigorous bounds on the condition number of $H$ and compare them to bounds for the higher dimensional Dirac operator of domain wall fermions. Our main conclusion is that overlap fermions should be taken seriously as a practical alternative to domain wall fermions in the context of numerical QCD.

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BibTeXRIS

R. Narayanan, H. Neuberger. 2000-06-30. An alternative to domain wall fermions. https://doi.org/10.1103/physrevd.62.074504

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