We give a vorticity-dynamical proof of C1∩H2-illposedness of the 2D Euler equations. Our construction shows that the unique Yudovich solution escapes both C1 and H2 instantaneously.
@article{arxiv.2211.13872,
title = {Velocity blow-up in $C^1\cap H^2$ for the 2D Euler equations},
author = {Min Jun Jo and Junha Kim},
journal= {arXiv preprint arXiv:2211.13872},
year = {2022}
}