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arXiv · 1907.06503

Alternative flow equation for the functional renormalization group

Elizabeth Alexander·Peter Millington·Jordan Nursey·Paul M. Saffin
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Abstract

We derive an alternative to the Wetterich-Morris-Ellwanger equation by means of the two-particle irreducible (2PI) effective action, exploiting the method of external sources due to Garbrecht and Millington. The latter allows the two-point source of the 2PI effective action to be associated consistently with the regulator of the renormalization group flow. We show that this procedure leads to a flow equation that differs from that obtained in the standard approach based on the average one-particle irreducible effective action.

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Elizabeth Alexander, Peter Millington, Jordan Nursey, Paul M. Saffin. 2019-07-15. Alternative flow equation for the functional renormalization group. https://doi.org/10.1103/physrevd.100.101702

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