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arXiv · 1202.3220

A Few Lessons from pQCD Analysis at Low Energies

D. V. Shirkov
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Abstract

Motivated by the recent 4-loop analysis of the JLab data on Bjorken Sum Rule, where the pQCD series seems to blow up at $|Q|\lesssim 1.5\,\GeV, α_s \gtrsim 0.33\,,$ we overview the general origin of the divergency of common perturbation expansion over powers of a small coupling parameter in QFT and consider in detail the {\it blowing-up phenomenon} and accuracy of finite sums for simple alternating and non-alternating examples of divergent series.

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D. V. Shirkov. 2012-02-15. A Few Lessons from pQCD Analysis at Low Energies. https://doi.org/10.1016/j.nuclphysbps.2012.02.002

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