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arXiv · 2311.07551

Low regularity well-posedness for the generalized surface quasi-geostrophic front equation

Albert Ai·Ovidiu-Neculai Avadanei
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Abstract

We consider the well-posedness of the generalized surface quasi-geostrophic (gSQG) front equation. By using the null structure of the equation via a paradifferential normal form analysis, we obtain balanced energy estimates, which allow us to prove the local well-posedness of the non-periodic gSQG front equation at a low level of regularity (in the SQG case, at only one-half derivatives above scaling). In addition, we establish global well-posedness for small and localized rough initial data, as well as modified scattering, by using the testing by wave packet approach of Ifrim-Tataru.

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Albert Ai, Ovidiu-Neculai Avadanei. 2023-11-13. Low regularity well-posedness for the generalized surface quasi-geostrophic front equation. https://doi.org/10.2140/paa.2026.8.271

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