Letter | Published:

Electromagnetic Level-Shift and Effect of Radiation Field

Nature volume 162, page 143 (24 July 1948) | Download Citation



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.

    , and , Phys. Rev., 72, 241 (1947).

  2. 2.

    , Phys. Rev., 72, 339 (1947).

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  1. University of Delhi.

    • D. S. KOTHARI
    •  & F. C. AULUCK


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