Renormalisation group flows for gauge theories in axial gauges

Journal of High Energy Physics (Impact Factor: 6.11). 02/2002; 2002(09). DOI: 10.1088/1126-6708/2002/09/049
Source: arXiv


Gauge theories in axial gauges are studied using Exact Renormalisation Group flows. We introduce a background field in the infrared regulator, but not in the gauge fixing, in contrast to the usual background field gauge. It is shown how heat-kernel methods can be used to obtain approximate solutions to the flow and the corresponding Ward identities. Expansion schemes are discussed, which are not applicable in covariant gauges. As an application, we derive the one-loop effective action for covariantly constant field strength, and the one-loop beta-function for arbitrary regulator. Comment: 27 pages, revtex, arguments detailed, references added, published in JHEP

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