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A simplified test of universality in Lattice QCD

David H. Adams
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Abstract

A simplified test of universality in Lattice QCD is performed by analytically evaluating the continuous Euclidean time limits of various lattice fermion determinants, both with and without a Wilson term to lift the fermion doubling on the Euclidean time axis, and comparing them with each other and with the zeta-regularised fermion determinant in the continuous time--lattice space setting. The determinant relations expected from universality considerations are found to be violated by a certain gauge field-dependent factor, i.e. we uncover a "universality anomaly". The physical significance, or lack thereof, of this factor is a delicate question which remains to be settled.

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David H. Adams. 2004-02-17. A simplified test of universality in Lattice QCD. https://doi.org/10.1103/physrevlett.92.162002

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