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arXiv · hep-ph/9611313

Derivation of the Lamb Shift using an Effective Field Theory

Patrick Labelle·S. Mohammad Zebarjad
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Abstract

We rederive the $O(α^5)$ shift of the hydrogen levels in the non-recoil ($m_e/m_P \to 0$) limit using Nonrelativistic QED (NRQED), an effective field theory developed by Caswell and Lepage (Phys. Lett. 167B, 437 (1986)). Our result contains the Lamb shift as a special case. Our calculation is far simpler than traditional approaches and has the advantage of being systematic. It also clearly illustrates the need to renormalize (or ``match'') the coefficients of the effective theory beyond tree level.

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Patrick Labelle, S. Mohammad Zebarjad. 1996-11-12. Derivation of the Lamb Shift using an Effective Field Theory. https://doi.org/10.1139/cjp-77-4-267

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