Quantum seminar | 17 December 2024

The electron self-energy is one of the most problematic effects in the hydrogen Lamb shift, whose theory is the cornerstone in the determination of the Rydberg constant. Recently, we were able to achieve a breakthrough in calculations of the electron self-energy [1,2] without any expansion in the nuclear binding strength parameter, basing on the method for improving the convergence of the partial-wave expansion suggested by Sapirstein and Cheng [3]. I will discuss the recent progress in one- and two-loop self-energy calculations and the consequences for the improved determination of the Rydberg constant.

Main paper/arXiv, related to the seminar, and other references:

1.  V. A. Yerokhin, Z. Harman, Ch. Keitel, Phys. Rev. Lett., in press.
2. V. A. Yerokhin, Z. Harman, Ch. Keitel, arXiv:2411.19135v1.
3. J. Sapirstein, K. T. Cheng, Phys. Rev. A 108, 042804 (2023).