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arXiv · 1308.0851

Global and local existence for the dissipative critical SQG equation with small oscillations

Omar Lazar
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Abstract

This article is devoted to the study of the critical dissipative surface quasi-geostrophic $(SQG)$ equation in $\mathbb{R}^2$. For any initial data $θ_{0}$ belonging to the space $Λ^{s} ( H^{s}_{uloc}(\mathbb{R}^2)) \cap L^\infty(\mathbb{R}^2)$, we show that the critical (SQG) equation has at least one global weak solution in time for all $1/4\leq s \leq 1/2$ and at least one local weak solution in time for all $0<s<1/4$. The proof for the global existence is based on a new energy inequality which improves the one obtain in \cite{Laz} whereas the local existence uses more refined energy estimates based on Besov space techniques.

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Omar Lazar. 2015-06-03. Global and local existence for the dissipative critical SQG equation with small oscillations. https://arxiv.org/abs/1308.0851

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