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Lamb shift calculated by simple noncovariant method

Guang-jiong Ni·Jun Yan
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Abstract

The Lamb Shift (LS) of Hydrogenlike atom is evaluated by a simple method of quantum electrodynamics in noncovariant form, based on the relativistic stationary Schrödinger equation. An induced term proportional to $\overrightarrow{p}^4$ in the effective Hamiltonian is emphasized. Perturbative calculation of second order leads to the LS of $ 1S_{1/2}$ state and that of $2S_{1/2}-2P_{1/2}$ states in H atom with the high accuracy within 0.1%

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Guang-jiong Ni, Jun Yan. 1999-01-08. Lamb shift calculated by simple noncovariant method. https://arxiv.org/abs/quant-ph/9901016

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