Exponential mixing by shear flows

William Cooperman

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arXiv · 2206.14239

Exponential mixing by shear flows

William Cooperman

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Abstract

We prove a version of Bressan's mixing conjecture where the advecting field is constrained to be a shear at each time. Also, inspired by recent work of Blumenthal, Coti Zelati and Gvalani, we construct a particularly simple example of a shear flow which mixes at the optimal rate. The constructed vector field alternates randomly in time between just two distinct shears.

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William Cooperman. 2022-06-28. Exponential mixing by shear flows. https://arxiv.org/abs/2206.14239

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