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arXiv · 2505.23936

A subsequentially fast dynamo on $\mathbb{T}^3$

Keefer Rowan
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Abstract

We construct a smooth velocity field $u$ on $\mathbb{R}_+ \times \mathbb{T}^3$ that exhibits kinematic dynamo action, causing exponential growth in solutions to the magnetohydrodynamic induction equation, with a rate that is uniform in diffusivity, for suitable sequences of diffusivity $\kappa_j \to 0.$ We call this a subsequentially fast dynamo, giving dynamo behavior intermediate between a truly slow dynamo and a truly fast dynamo.

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Keefer Rowan. 2025-05-29. A subsequentially fast dynamo on $\mathbb{T}^3$. https://arxiv.org/abs/2505.23936

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