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arXiv · 1205.1835

A Cusp in QED at g=2

Johann Rafelski·Lance Labun
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Abstract

We explore nonperturbative properties of QED allowing a gyromagnetic ratio $g\ne g_{\rm D}\equiv 2$. We study the effective action $V_{\mathrm{eff}}$ for an arbitrarily strong constant and homogeneous field. Using the external field method, we find a cusp as a function of the gyromagnetic factor $g$ in: a) The QED $b_0$-renormalization group coefficient; b) A subclass of light-light scattering coefficients obtained in the long wavelength limit expansion. We recognize possibility of asymptotic freedom in an Abelian theory for certain domains of $g$.

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Johann Rafelski, Lance Labun. 2012-05-08. A Cusp in QED at g=2. https://doi.org/10.1103/physrevd.107.076002

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