Thời gian: 9h30, Thứ 3, ngày 10/2/2015

 Địa điểm: Phòng 4, Nhà A14, Viện Toán học, 18 Hoàng Quốc Việt Cầu Giấy, Hà Nội

Tóm tắt: The 1-d cubic nonlinear Schro''dinger equation (NLS) has a special solution called isolated soliton $e^{it} frac{sqrt(2)}{ cosh x}$. There are many results about the nonlinear stability or instability of this solution for 1-d or 2-d cubic nonlinear Schro''dinger equation. Otherwise, Davey-Stewartson system (DS) is a two dimensional perturbation of 1-d cubic nonlinear Schro''dinger equation, so it is interested to study the nonlinear (in-)stability of this soliton under time evolution of this two dimensional model. In this talk, i will present some known results about Davey-Stewartson system, nonlinear (in-)stability of the isolated soliton and discuss some open questions.