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Landau gauge ghost and gluon propagators and the Faddeev-Popov operator spectrum

A. Sternbeck·E. -M. Ilgenfritz·M. Müller-Preussker·A. Schiller
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Abstract

In this talk we report on a recent lattice investigation of the Landau gauge gluon and ghost propagators in pure SU(3) lattice gauge theory with a special emphasis on the Gribov copy problem. In the (infrared) region of momenta $q^2 \le 0.3 \mathrm{GeV}^2$ we find the corresponding MOM scheme running coupling $α_s(q^2)$ to rise in $q$. We also report on a first SU(3) computation of the ghost-gluon vertex function showing that it deviates only weakly from being constant. In addition we study the spectrum of low-lying eigenvalues and eigenfunctions of the Faddeev-Popov operator as well as the spectral representation of the ghost propagator.

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A. Sternbeck, E. -M. Ilgenfritz, M. Müller-Preussker, A. Schiller. 2005-11-23. Landau gauge ghost and gluon propagators and the Faddeev-Popov operator spectrum. https://doi.org/10.1016/j.nuclphysbps.2006.01.048

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