Asymptotics, frequency modulation, and low regularity ill-posedness for canonical defocusing equations

Michael Christ, James Colliander, Terence Tao

In a recent paper, Kenig, Ponce and Vega study the low regularity behavior of the focusing nonlinear Schrödinger (NLS), focusing modified Korteweg-de Vries (mKdV), and complex Kort…