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arXiv · 1003.4792

Spectral sum for the color-Coulomb potential in SU(3) Coulomb gauge lattice Yang-Mills theory

Y. Nakagawa·A. Nakamura·T. Saito·H. Toki
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Abstract

We discuss the essential role of the low-lying eigenmodes of the Faddeev-Popov (FP) ghost operator on the confining color-Coulomb potential using SU(3) quenched lattice simulations in the Coulomb gauge. The color-Coulomb potential is expressed as a spectral sum of the FP ghost operator and has been explored by partially summing the FP eigenmodes. We take into account the Gribov copy effects that have a great impact on the FP eigenvalues and the color-Coulomb potential. We observe that the lowest eigenvalue vanishes in the thermodynamic limit much faster than that in the Landau gauge. The color-Coulomb potential at large distances is governed by the near-zero FP eigenmodes; in particular, the lowest one accounts for a substantial portion of the color-Coulomb string tension comparable to the Wilson string tension.

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Y. Nakagawa, A. Nakamura, T. Saito, H. Toki. 2010-03-25. Spectral sum for the color-Coulomb potential in SU(3) Coulomb gauge lattice Yang-Mills theory. https://doi.org/10.1103/physrevd.81.054509

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