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arXiv · 1910.04820

Three-dimensional magnetohydrodynamics system forced by space-time white noise

Kazuo Yamazaki
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Abstract

We consider the three-dimensional magnetohydrodynamics system forced by noise that is white in both time and space. Its complexity due to four non-linear terms makes its analysis very intricate. Nevertheless, taking advantage of its structure and adapting the theory of paracontrolled distributions from \cite{GIP15}, we prove its local well-posedness. A first challenge is to find an appropriate paracontrolled ansatz which must consist of both the velocity and the magnetic fields. Second challenge is that for some non-linear terms, renormalizations cannot be achieved individually; we overcome this obstacle by strategically coupling certain terms together rather than separately. Our proof is also inspired by the work of \cite{ZZ15}.

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Kazuo Yamazaki. 2019-10-10. Three-dimensional magnetohydrodynamics system forced by space-time white noise. https://arxiv.org/abs/1910.04820

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