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arXiv · hep-ph/9503416

The Foldy-Wouthuysen transformation

John P. Costella·Bruce H. J. McKellar
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Abstract

The Foldy-Wouthuysen transformation of the Dirac Hamiltonian is generally taught as simply a mathematical trick that allows one to obtain a two-component theory in the low-energy limit. It is not often emphasized that the transformed representation is the only one in which one can take a meaningful *classical limit*, in terms of particles and antiparticles. We briefly review the history and physics of this transformation.

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John P. Costella, Bruce H. J. McKellar. 1995-03-23. The Foldy-Wouthuysen transformation. https://doi.org/10.1119/1.18017

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