Electromagnetic Level-Shift and Effect of Radiation Field

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THE brilliant experiment of Lamb and Retherford1 has conclusively demonstrated that in the hydrogen atom the 2S-level is higher than the 2P1/2-level by about 10 megacycles, a result which reveals a breakdown of the Dirac equation of the electron when applied even to the simplest of the atoms. In a fundamental paper, Bethe2 has given an explanation of the observed level-shift on the assumption that the transverse self-energy of the electron, in general, depends on the state in which the electron is.

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  1. 1

    Lamb, W. E., and Retherford, R. L., Phys. Rev., 72, 241 (1947).

  2. 2

    Bethe, H. A., Phys. Rev., 72, 339 (1947).

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KOTHARI, D., AULUCK, F. Electromagnetic Level-Shift and Effect of Radiation Field. Nature 162, 143 (1948) doi:10.1038/162143b0

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