arXiv 1007.12112010-07math.AP

Global well-posedness for an advection-diffusion equation arising in magneto-geostrophic dynamics

Susan Friedlander, Vlad Vicol

备注：: To appear in Annales de l'Institut Henri Poincare - Analyse non lineaire
DOI：: 10.1016/j.anihpc.2011.01.002

英文摘要：

We use De Giorgi techniques to prove Hölder continuity of weak solutions to a class of drift-diffusion equations, with $L^2$ initial data and divergence free drift velocity that lies in $L_{t}^{\infty}BMO_{x}^{-1}$. We apply this result to prove global regularity for a family of active scalar equations which includes the advection-diffusion equation that has been proposed by Moffatt in the context of magnetostrophic turbulence in the Earth's fluid core.

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