The results of QED calcualtions are in the form of an asymptotic series in the fine structure constant. This means that if one adds too many terms, the result diverges. So what is the meaning of "18 digits accuracy" of certain QED calculations, if they can be spoiled by adding MORE loops to the calculation or LESS ?(adsbygoogle = window.adsbygoogle || []).push({});

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# How can an asymptotic series give accurate results as in QED?

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