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arXiv · 2311.14638

Master Formulae for $N$-photon tree level amplitudes in plane wave backgrounds

Patrick Copinger·James P. Edwards·Anton Ilderton·Karthik Rajeev
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Abstract

The presence of strong electromagnetic fields adds huge complexity to QED Feynman diagrams, such that new methods are required to calculate higher-loop and higher-multiplicity scattering amplitudes. Here we use the worldline formalism to present `Master Formulae' for all tree level amplitudes of two massive particles and an arbitrary number of photons, in a plane wave background, in both scalar and spinor QED. The plane wave is treated without approximation throughout, meaning in particular that our formulae are valid in the strong-field regime of current theoretical and experimental interest. We check our results against literature expressions obtainable at low multiplicity via direct Feynman diagram calculations.

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Patrick Copinger, James P. Edwards, Anton Ilderton, Karthik Rajeev. 2023-11-24. Master Formulae for $N$-photon tree level amplitudes in plane wave backgrounds. https://arxiv.org/abs/2311.14638

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