Relativistic corrections of order $m\alpha^6$: singular operators and regularization

Vladimir I Korobov

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arXiv · 2505.16645

Relativistic corrections of order $m\alpha^6$: singular operators and regularization

Vladimir I Korobov

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Abstract

The finite operators are derived for the nonrecoil (leading order in the $(m/M)$ expansion) relativistic corrections in hydrogen-like atoms and ions at orders $m\alpha^6$ in the two- and three-body formalism beyond the adiabatic approximation. Singular operators that appear in the derivation are analysed, and various regularization methods are discussed.

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Vladimir I Korobov. 2025-05-22. Relativistic corrections of order $m\alpha^6$: singular operators and regularization. https://arxiv.org/abs/2505.16645

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