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arXiv · 2301.13477

Pre-Born-Oppenheimer Dirac-Coulomb-Breit computations for two-body systems

Dávid Ferenc·Edit Mátyus
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Abstract

The sixteen-component, no-pair Dirac--Coulomb--Breit equation, derived from the Bethe--Salpeter equation, is solved in a variational procedure using Gaussian-type basis functions for the example of positronium, muonium, hydrogen atom, and muonic hydrogen. The $\alpha$ fine-structure-constant dependence of the variational energies, through fitting a function of $\alpha^n$ and $\alpha^n\text{ln}\alpha$ terms, shows excellent agreement with the relevant energy expressions of the (perturbative) non-relativistic QED framework, and thereby, establishes a solid reference for the development of a computational relativistic QED approach.

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Dávid Ferenc, Edit Mátyus. 2023-01-31. Pre-Born-Oppenheimer Dirac-Coulomb-Breit computations for two-body systems. https://doi.org/10.1103/physreva.107.052803

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