Fast evaluation and locality of overlap fermions
نویسنده
چکیده
A 0 A0, so that Dov = Aov + μ obeys the GWR (for μ in some allowed interval). The standard Neuberger fermion uses the Wilson operator D0 = DW [4]. The guide-line for our concept to improve overlap fermions [5] is the following observation: ifD0 is already a GW fermion (with respect to a fixed kernel R), then Dov = D0. We can explicitly construct an approximate solution to the GWR, use it as D0, and then we expect that the overlap formula only causes a small “chiral correction”,
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