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arXiv · 1506.04491

Loop expansion of the average effective action in the functional renormalization group approach

Peter M. Lavrov·Boris S. Merzlikin
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Abstract

We formulate a perturbation expansion for the effective action in a new approach to the functional renormalization group method based on the concept of composite fields for regulator functions being their most essential ingredients. We demonstrate explicitly the principal difference between the properties of effective actions in these two approaches existing already on the one-loop level in a simple gauge model.

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Peter M. Lavrov, Boris S. Merzlikin. 2015-12-23. Loop expansion of the average effective action in the functional renormalization group approach. https://doi.org/10.1103/physrevd.92.085038

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