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Numerical studies of confinement in the lattice Landau gauge

Hideo Nakajima·Sadataka Furui·Azusa Yamaguchi
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Abstract

Critical conjectures on confinement in the Landau gauge is numerically tested in focus to Gribov copy effects. One of the subjects is of the Kugo-Ojima confinement criterion and the other is of various viewpoints in the Gribov-Zwanziger theory. We use the smearing gauge as a reference gauge free of Gribov copy, and performed three types of simulations, log U, U-linear and log U in the smearing gauge. It is found that Gribov copy effect on the Kugo-Ojima parameter is small. log U and U-linear simulations yield only global scale factor difference in gluon propagator and in ghost propagator, and about 10% difference in Kugo-Ojima parameter. The horizon function defined by Zwanziger is evaluated in three types of gauge field and compared. All data show the negative horizon function as expected.

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Hideo Nakajima, Sadataka Furui, Azusa Yamaguchi. 2002-04-11. Numerical studies of confinement in the lattice Landau gauge. https://doi.org/10.1016/s0920-5632(01)00866-0

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