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arXiv · 0712.2379

Gribov copies and anomalous scaling

Abstract

Nonperturbative and lattice methods indicate that Gribov copies modify the infrared behavior of gauge theories and cause a suppression of gluon propagation. We investigate whether this can be implemented in a modified perturbation theory. The minimal modification proceeds via a nonlocal generalization of the Fadeev-Popov ghost that automatically decouples from physical states. The expected scale invariance of the physics associated with Gribov copies leads to the emergence of a nontrivial infrared fixed point. For a range of a scaling exponent the gauge bosons exhibit unparticlelike behavior in the infrared. The confining regime of interest for QCD requires a larger scaling exponent, but then the severity of ghost dominance upsets naive power counting for the infrared scaling behavior of amplitudes.

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B. Holdom. 2009-01-05. Gribov copies and anomalous scaling. https://doi.org/10.1103/physrevd.78.125030

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