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On the fourth root prescription for dynamical staggered fermions

David H. Adams
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Abstract

With the aim of resolving theoretical issues associated with the fourth root prescription for dynamical staggered fermions in Lattice QCD simulations, we consider the problem of finding a viable lattice Dirac operator D such that (det D_{staggered})^{1/4} = det D. Working in the flavour field representation we show that in the free field case there is a simple and natural candidate D satisfying this relation, and we show that it has acceptable locality behavior: exponentially local with localisation range vanishing ~ (a/m)^{1/2} for lattice spacing a -> 0. Prospects for the interacting case are also discussed, although we do not solve this case here.

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David H. Adams. 2005-10-27. On the fourth root prescription for dynamical staggered fermions. https://doi.org/10.1103/physrevd.72.114512

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