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The non-retarded dispersive force between an electrically polarizable atom and a magnetically polarizable one

C. Farina·F. C. Santos·A. C. Tort
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Abstract

Using perturbative QED we show that, while the retarded dispersive force between an electrically polarizable atom and a magnetically polarizable one is proportional to $1/r^{8}$, where $r$ is the distance between the atoms, the non-retarded force is proportiaonal to $1/r^{5}$. This is a rather surprising result that should be compared with the dispersive van der Waals force between two electrically polarizable atoms, where the retarded force is also proportional to $1/r^{8}$, but the non-retarded force is proportional to $1/r^{7}$.

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C. Farina, F. C. Santos, A. C. Tort. 2000-07-24. The non-retarded dispersive force between an electrically polarizable atom and a magnetically polarizable one. https://arxiv.org/abs/hep-th/0007190

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