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arXiv · hep-th/9703106

Singlet-Triplet Splitting of Positronium in Light-Front QED

Billy D. Jones
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Abstract

We study the QED bound-state problem in a light-front hamiltonian approach. It is important to establish the equivalence (or not) of equal-time and light-front approaches in the well-understood arena of Quantum Electrodynamics. Along these lines, the singlet-triplet ground state spin splitting in positronium is calculated. The well-known result, $(7/6) α^2 Ryd$, is obtained analytically, which establishes the equivalence between the equal-time and light-front approaches (at least to this order). The true equivalence of the two approaches can only be established after higher-order calculations. It was previously shown that this light-front result could be obtained analytically, but a simpler method is presented in this paper.

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Billy D. Jones. 1997-03-14. Singlet-Triplet Splitting of Positronium in Light-Front QED. https://arxiv.org/abs/hep-th/9703106

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