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Vertex functions and infrared fixed point in Landau gauge SU(N) Yang-Mills theory

Reinhard Alkofer·Christian S. Fischer·Felipe J. Llanes-Estrada
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Abstract

The infrared behaviour of vertex functions in an SU(N) Yang-Mills theory in Landau gauge is investigated employing a skeleton expansion of the Dyson-Schwinger equations. The three- and four-gluon vertices become singular if and only if all external momenta vanish while the dressing of the ghost-gluon vertex remains finite in this limit. The running coupling as extracted from either of these vertex functions possesses an infrared fixed point. In general, diagrams including ghost-loops dominate in the infrared over purely gluonic ones.

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Reinhard Alkofer, Christian S. Fischer, Felipe J. Llanes-Estrada. 2005-03-08. Vertex functions and infrared fixed point in Landau gauge SU(N) Yang-Mills theory. https://doi.org/10.1016/j.physletb.2005.02.043%2010.1016%2Fj.physletb.2008.11.068

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