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Eight-component differential equation for leptonium

R. Haeckl·V. Hund·H. Pilkuhn
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Abstract

It is shown that the potential for lepton-antilepton bound states (leptonium) is the Fourier transform of the first Born approximation to the QED scattering amplitude in an 8-component equation, while 16-component equations are excluded. The Fourier transform is exact at all cms energies $-\infty < E < \infty$; the resulting atomic spectrum is explicitly CPT-invariant.

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R. Haeckl, V. Hund, H. Pilkuhn. 1996-11-05. Eight-component differential equation for leptonium. https://arxiv.org/abs/physics/9611004

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