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arXiv · 0907.4138

Covariant gauge on the lattice: a new implementation

Attilio Cucchieri·Tereza Mendes·Elton M. S. Santos
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Abstract

We derive a new implementation of linear covariant gauges on the lattice, based on a minimizing functional that can be interpreted as the Hamiltonian of a spin-glass model in a random external magnetic field. We show that our method solves most problems encountered in earlier implementations, mostly related to the no-go condition formulated by L. Giusti, Nucl. Phys. B 498, 331 (1997). We carry out tests in the SU(2) case in four space-time dimensions. We also present preliminary results for the transverse gluon propagator at different values of the gauge parameter xi.

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Attilio Cucchieri, Tereza Mendes, Elton M. S. Santos. 2009-09-29. Covariant gauge on the lattice: a new implementation. https://doi.org/10.1103/physrevlett.103.141602

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