Septic NLW/NLKG on R

Scaling is $s c = 1 / 6$ .
LWP for by energy estimates and Sobolev (solution is in )
- For $s < 5 / 14$ it is not even possible to make sense of the solution as a distribution (note there are no smoothing effects for the 1D wave equation!) and so there is ill-posedness CtCoTa-p2.
GWP for $s = 1$ in the defocusing case by energy conservation. Presumably this is improvable.