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arXiv · 1010.5636

Implementation of the Neuberger-Dirac operator on GPUs

Bjoern Walk·Hartmut Wittig·Egor Dranischnikow·Elmar Schömer
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Abstract

Recent developments have shown that a lot can be gained for QCD simulations from GPU hardware. This can be exploited especially in the case of Ginsparg-Wilson fermions when the com putational costs are particularly high. In this work, we use the Neuberger-Dirac operator as our realisation of Ginsparg-Wilson fermions, which greatly facilitate lattice investigations of decays like $K \to ππ$. We report on the ongoing study of our GPU implementation of the Neuberger-Dirac operator including the exact treatment of the low lying eigenmodes of the Wilson-Dirac operator. Our benchmarks show that we achieve speed-up factors of around 23 and 16 in single and double precision, respectively.

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Bjoern Walk, Hartmut Wittig, Egor Dranischnikow, Elmar Schömer. 2010-10-27. Implementation of the Neuberger-Dirac operator on GPUs. https://arxiv.org/abs/1010.5636

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