On the stability of the ill-posedness of a quasi-linear wave equation in two dimensions with initial data in $H^{7/4}(\ln H^{-\beta })$

Gaspard Ohlmann

This article is the continuation of \cite{ohlmann2021illposedness} where we exhibited the ill-posedness of a quasi-linear wave equation in dimension $2$ for initial data in $H^{7/4…