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arXiv · 1801.09040

Oscillations and integrability of the vorticity in the 3D NS flows

Y. Do·A. Farhat·Z. Grujic·L. Xu
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Abstract

In the studies of the Navier-Stokes (NS) regularity problem, it has become increasingly clear that a more realistic path to improved a priori bounds is to try to break away from the scaling of the energy-level estimates in the realm of the blow-up-type arguments (the solution in view is regular/smooth up to the possible blow-up time) rather than to try to improve regularity of arbitrary Leray's weak solutions. The present article is a contribution in this direction; more precisely, it is shown--in the context of an algebraic/polynomial-type blow-up profile of arbitrary degree--that a very weak condition on the vorticity direction field (membership in a local $bmo$ space weighted with arbitrary many logarithms)--suffices to break the energy-level scaling in the bounds on the vorticity. At the same time, the obtained bounds transform a 3D NS criticality scenario depicted by the macro-scale long vortex filaments into a no-singularity scenario.

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Y. Do, A. Farhat, Z. Grujic, L. Xu. 2018-01-27. Oscillations and integrability of the vorticity in the 3D NS flows. https://arxiv.org/abs/1801.09040

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