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arXiv · hep-lat/9710020

QED2 as a testbed for interpolations between quenched and full QCD

W. Bardeen·A. Duncan·E. Eichten·H. Thacker
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Abstract

Lattice QED2 with the Wilson formulation of fermions is used as a convenient model system to study artifacts of the quenched approximation on a finite lattice. The quenched functional integral is shown to be ill-defined in this system as a consequence of the appearance of exactly real modes for physical values of the fermion mass. The location and frequency of such modes is studied as a function of lattice spacing, lattice volume, topological charge and improved action parameters. The efficacy of the recently proposed modified quenched approximation is examined, as well as a new approach to the interpolation from the quenched to full dynamical theory employing a truncated form of the fermion determinant.

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W. Bardeen, A. Duncan, E. Eichten, H. Thacker. 1997-10-03. QED2 as a testbed for interpolations between quenched and full QCD. https://doi.org/10.1016/s0920-5632(97)00908-0

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