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arXiv · 2107.12914

Benchmarking regulator-sourced 2PI and average 1PI flow equations in zero dimensions

Peter Millington·Paul M. Saffin
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Abstract

We elucidate the regulator-sourced 2PI and average 1PI approaches for deriving exact flow equations in the case of a zero dimensional quantum field theory, wherein the scale dependence of the usual renormalisation group evolution is replaced by a simple parametric dependence. We show that both approaches are self-consistent, while highlighting key differences in their behaviour and the structure of the would-be loop expansion.

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Peter Millington, Paul M. Saffin. 2021-07-27. Benchmarking regulator-sourced 2PI and average 1PI flow equations in zero dimensions. https://doi.org/10.1088/1751-8121%2Fac2d00

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