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arXiv · 2107.04073

Uniqueness and non-uniqueness results for dyadic MHD models

Mimi Dai·Susan Friedlander
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Abstract

We construct non-unique Leray-Hopf solutions for some dyadic models for magnetohydrodynamics when the intermittency dimension $\delta$ is less than 1. In contrast, uniqueness of Leray-Hopf solution is established in the case of $\delta\geq 1$. Analogous results on uniqueness and non-uniqueness of Leray-Hopf solution are also obtained for dyadic models of MHD with fractional diffusion.

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Mimi Dai, Susan Friedlander. 2021-07-08. Uniqueness and non-uniqueness results for dyadic MHD models. https://arxiv.org/abs/2107.04073

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