On the squared spin-orbit correction to the positronium fine-structure splitting

I. B. Khriplovich; A. I. Milstein; A. S. Yelkhovsky

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On the squared spin-orbit correction to the positronium fine-structure splitting

I. B. Khriplovich·A. I. Milstein·A. S. Yelkhovsky

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Abstract

In the recent paper by Zhang the order $α^4 R_{\infty}$ corrections to the positronium P levels were reconsidered. Those calculations confirm our corresponding results, except for the contribution due to the squared spin-orbit interaction. We present here a new derivation of our previous result for this last correction, this derivation being to our opinion both simple and convincing.

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I. B. Khriplovich, A. I. Milstein, A. S. Yelkhovsky. 1996-11-26. On the squared spin-orbit correction to the positronium fine-structure splitting. https://arxiv.org/abs/physics/9611021

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