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arXiv · 2501.04704

Dirac-Schwinger Quantization for Emergent Magnetic Monopoles?

A. Farhan·M. Saccone·B. F. L. Ward
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Abstract

In Refs.[1-4] Dirac and Schwinger showed the existence of a magnetic monopole required a charge quantization condition which we write following Dirac as $\frac{eg}{4\pi\hbar}=\frac{n}{2},\; n=0,\pm 1,\; \pm 2, \ldots$. Here, $g$ is the magnetic monopole charge and $e$ is the electric charge of the positron. Recently, in Refs. [5,6], it has been shown experimentally that frustrated spin-ice systems exhibit 'emergent' magnetic monopoles. We show that, within the experimental errors, the respective magnetic charges obey the Dirac-Schwinger quantization condition. Possible implications are discussed.

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A. Farhan, M. Saccone, B. F. L. Ward. 2024-12-23. Dirac-Schwinger Quantization for Emergent Magnetic Monopoles?. https://doi.org/10.1016/j.physletb.2025.139496

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