• DOI:10.1063/5.0018569
• Corpus ID: 219687581

On general-relativistic hydrogen and hydrogenic ions

@article{Kiessling2020OnGH,
  title={On general-relativistic hydrogen and hydrogenic ions},
  author={Michael K.-H. Kiessling and A. Shadi Tahvildar-Zadeh and Ebru Toprak},
  journal={Journal of Mathematical Physics},
  year={2020},
  volume={61},
  pages={092303}
}

• M. Kiessling, A. Tahvildar-Zadeh, E. Toprak
• Published 15 June 2020
• Physics
• Journal of Mathematical Physics

This paper studies how the static non-linear electromagnetic-vacuum spacetime of a point nucleus with a negative bare mass affects the self-adjointness of the general-relativistic Dirac Hamiltonian for a test electron, without and with an anomalous magnetic moment. This study interpolates between the previously studied extreme cases of a test electron in (a) the Reissner–Weyl–Nordstrom spacetime (Maxwell’s electromagnetic vacuum), which sports a very strong curvature singularity with negative infinite bare mass, and (b) the Hoffmann spacetime (Born or Born–Infeld’s electromagnetic vacuum) with vanishing bare mass, which features the mildest possible curvature singularity. The main conclusion reached is: on electrostatic spacetimes of a point nucleus with a strictly negative bare mass (which may be −∞), essential self-adjointness fails unless the radial electric field diverges sufficiently fast at the nucleus and the anomalous magnetic moment of the electron is taken into account. Thus, on the Hoffmann spacetime with a (strictly) negative bare mass, the Dirac Hamiltonian of a test electron, with or without anomalous magnetic moment, is not essentially self-adjoint. All these operators have self-adjoint extensions, though, with the usual essential spectrum (−∞, −mec2] ∪ [mec2, ∞) and an infinite discrete spectrum located in the gap (−mec2, mec2).