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arXiv · hep-lat/0508023

Heavy quark propagators with improved precision using domain decomposition

A. Juttner·M. Della Morte
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Abstract

We show that, in four dimensions, the quark propagator is affected by round-off errors for large values of the quark mass am and the time extent T/a even when double precision arithmetics is used to compute it. We introduce a definition of the solver residual which is sensitive to the problem and apply a Schwarz alternating procedure to compute the propagator in a number of sub-domains in the time direction. The effectiveness of the method is demonstrated in a numerical computation of the free one-dimensional Dirac propagator.

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A. Juttner, M. Della Morte. 2005-08-25. Heavy quark propagators with improved precision using domain decomposition. https://arxiv.org/abs/hep-lat/0508023

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