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A variant approach to the overlap action

Thomas DeGrand
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Abstract

I describe an implementation of the overlap action, which is built from an action which is itself an approximate overlap action. It appears to be about a factor of 15-20 less expensive to use, than the usual overlap action with the Wilson fermion action as its kernel. Ingredients include a fat link to suppress coupling to dislocations and a free field action with a spectrum which resembles an overlap; much of the gain comes from the use of eigenmodes of the approximate action to begin the overlap calculation. As a physics example, I compute the quark condensate in finite volume in the quenched approximation.

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Thomas DeGrand. 2000-07-28. A variant approach to the overlap action. https://doi.org/10.1103/physrevd.63.034503

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