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arXiv · 2003.08397

Towards the QED beta function and renormalons at $1/N_f^2$ and $1/N_f^3$

Nicola Andrea Dondi·Gerald V. Dunne·Manuel Reichert·Francesco Sannino
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Abstract

We determine the $1/N_f^2$ and $1/N_f^3$ contributions to the QED beta function stemming from the closed set of nested diagrams. At order $1/N_f^2$ we discover a new logarithmic branch-cut closer to the origin when compared to the $1/N_f$ results. The same singularity location appears at $1/N_f^3$, and these correspond to a UV renormalon singularity in the finite part of the photon two-point function.

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Nicola Andrea Dondi, Gerald V. Dunne, Manuel Reichert, Francesco Sannino. 2020-03-18. Towards the QED beta function and renormalons at $1/N_f^2$ and $1/N_f^3$. https://doi.org/10.1103/physrevd.102.035005

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