In this note, we study the ill-posedness problem for the derivative nonlinear Schr & ouml;dinger equation (DNLS) in the one-dimensional setting. More precisely, by using a ternary-quinary tree expansion of the Duhamel formula we prove norm inflation in Sob ...
We present a simple PDE construction of the sine‐Gordon measure below the first threshold (), in both the finite and infinite volume settings, by studying the corresponding parabolic sine‐Gordon model. We also establish pathwise global well‐posedness of th ...