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arXiv · 1305.3133

Fractional Effective Action at strong electromagnetic fields

Hagen Kleinert·Eckhard Strobel·She-Sheng Xue
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Abstract

In 1936, Weisskopf showed that for vanishing electric or magnetic fields the strong-field behavior of the one loop Euler-Heisenberg effective Lagrangian of quantum electro dynamics (QED) is logarithmic. Here we generalize this result for different limits of the Lorentz invariants \(\vec{E}^2-\vec{B}^2\) and \(\vec{B}\cdot\vec{E}\). The logarithmic dependence can be interpreted as a lowest-order manifestation of an anomalous power behavior of the effective Lagrangian of QED, with critical exponents \(δ=e^2/(12π)\) for spinor QED, and \(δ_S=δ/4\) for scalar QED.

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Hagen Kleinert, Eckhard Strobel, She-Sheng Xue. 2013-08-07. Fractional Effective Action at strong electromagnetic fields. https://doi.org/10.1103/physrevd.88.025049

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