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arXiv · 2509.00021

Closed Foldy-Wouthuysen transformations for fermions moving in gauge-invariant time-dependent electromagnetic fields

V. P. Neznamov
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Abstract

Previously, we obtained closed expressions for energy operators in the Foldy-Wouthuysen representation in the presence of static electric fields. In this case, we also established a connection between the Foldy-Wouthuysen representation and the Feynman-Gell-Mann representation. In this work, we generalize these results for the case of fermions moving in time-dependent gauge-invariant electromagnetic fields.

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V. P. Neznamov. 2025-08-18. Closed Foldy-Wouthuysen transformations for fermions moving in gauge-invariant time-dependent electromagnetic fields. https://doi.org/10.1142/s0217751x25500745

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