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A Non-perturbative Estimate of Vacuum Polarization in QED

Y. M. Cho·D. G. Pak
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Abstract

We present a new estimate of the fine structure constant and the $β$-function of QED at an arbitrary scale. Using the non-perturbative but convergent series expression of the one loop effective action of QED that has been available recently we make a non-perturbative estimate of the running coupling and the $β$-function, and prove the renormalization group invariance of the effective action. The contrast between our result and the perturbative result is remarkable.

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Y. M. Cho, D. G. Pak. 2001-09-05. A Non-perturbative Estimate of Vacuum Polarization in QED. https://arxiv.org/abs/hep-th/0010073

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