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arXiv · 2406.09562

Monopole magnetohydrodynamics on a plane: Magnetosonic waves and dynamo instability

Debarghya Banerjee·Roderich Moessner·Piotr Surówka
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Abstract

Condensed matter systems can host emergent `vacua' with particles, fields and dimension different from that of the universe we inhabit. Motivated by the appearance of emergent gauge fields with both electric and magnetic charges, we consider the fate of electromagnetism in two dimensions in the presence of magnetic monopoles. We find that generically electromagnetic fields are damped due to resistive effects. However, we can still identify a magnetohydrodynamic regime. It exhibits magnetosonic waves which, unlike in $d=3$, are isotropic, to which there is a contribution from the odd viscosity coefficient present in the system. Further, we find a dynamo action, which unlike in $d=3$ requires compressibility of the flow.

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Debarghya Banerjee, Roderich Moessner, Piotr Surówka. 2024-06-13. Monopole magnetohydrodynamics on a plane: Magnetosonic waves and dynamo instability. https://arxiv.org/abs/2406.09562

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