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On the Calculation of QED Amplitudes in a Constant Field

Christian Schubert
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Abstract

It is explained how first-quantized worldline path integrals can be used as an efficient alternative to Feynman diagrams in the calculation of QED amplitudes and effective actions. The examples include the one-loop photon splitting amplitude, the two-loop Euler-Heisenberg Lagrangian, and the one-loop axial vacuum polarization tensor in a general constant electromagnetic field.

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Christian Schubert. 1998-07-08. On the Calculation of QED Amplitudes in a Constant Field. https://arxiv.org/abs/hep-ph/9807288

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