Instability of 2D Couette Flow in Low Regularity Spaces
发布时间：2017年12月25日
浏览次数：6540
发布者: He Liu
主讲人： Yu Deng (New York University)
活动时间： 从 2017-12-26 14:00 到 15:00
场地： 北京国际数学研究中心，镜春园78号院（怀新园）78201室
In 2013, Bedrossian and Masmoudi proved the stability and asymptotic stability of the Couette flow on T*R for small perturbations in Gevrey class G^(2-). Here, a natural question is whether this high regularity requirement can be relaxed. In this talk, I will present recent work joint with Nader Masmoudi that establishes the optimality of this Gevrey exponent, by proving instability of the Couette flow for small perturbations in any Gevrey class G^(2+). The main ingredients in the proof are: a detailed study of the "toy model" introduced in the work of Bedrossian-Masmoudi, carefully selected perturbations and higher order perturbations, and a combination of physical space and Fourier space techniques.
