Instability of 2D Couette Flow in Low Regularity Spaces
主 题: Instability of 2D Couette Flow in Low Regularity Spaces
报告人: Yu Deng (New York University)
时 间: 2017-12-26 14:00 - 2017-12-26 15:00
地 点: Room 78201, Jingchunyuan 78, BICMR
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In 2013, Bedrossian and Masmoudi proved the stability and <\/span>asymptotic stability of the Couette flow on T*R for small perturbations in <\/span>Gevrey class G^(2-). Here, a natural question is whether this high <\/span>regularity requirement can be relaxed. In this talk, I will present recent <\/span>work joint with Nader Masmoudi that establishes the optimality of this <\/span>Gevrey exponent, by proving instability of the Couette flow for small <\/span>perturbations in any Gevrey class G^(2+). The main ingredients in the <\/span>proof are: a detailed study of the "toy model" introduced in the work of <\/span>Bedrossian-Masmoudi, carefully selected perturbations and higher order <\/span>perturbations, and a combination of physical space and Fourier space <\/span>techniques.<\/span>\n<\/div>
