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arXiv · 2206.08865

Vertex functions and their flow equations from the 2PI effective action

Peter Millington·Paul M. Saffin
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Abstract

By exploiting the convexity of the two-particle-irreducible (2PI) effective action, we describe a procedure for extracting n-point vertex functions. This procedure is developed within the context of a zero-dimensional "quantum field theory" and subsequently extended to higher dimensions. These results extend the practicability and utility of a recent, alternative approach to the functional renormalization group programme [see arXiv:1907.06503; arXiv:2107.12914], and clarify the relationship between the flow equations for coupling parameters and vertices.

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Peter Millington, Paul M. Saffin. 2022-06-17. Vertex functions and their flow equations from the 2PI effective action. https://doi.org/10.1088/1751-8121%2Fac99ae

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