Regularity, uniqueness and the relative size of small and large scales in SQG flows

Zachary Akridge; Zachary Bradshaw

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arXiv · 2411.15040

Regularity, uniqueness and the relative size of small and large scales in SQG flows

Zachary Akridge·Zachary Bradshaw

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Abstract

The problem of regularity and uniqueness are open for the supercritically dissipative surface quasi-geostrophic equations in certain classes. In this note we examine the extent to which small or large scales are necessarily active both for the temperature in a hypothetical blow-up scenario and for the error in hypothetical non-uniqueness scenarios, the latter understood within the class of Marchand's solutions. This extends prior work for the 3D Navier-Stokes equations. The extension is complicated by the fact that mild solution techniques are unavailable for supercritical SQG. This forces us to develop a new approach using energy methods and Littlewood-Paley theory.

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Zachary Akridge, Zachary Bradshaw. 2024-11-22. Regularity, uniqueness and the relative size of small and large scales in SQG flows. https://arxiv.org/abs/2411.15040

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