Let $H^r(\Omega) = W^{r, 2}(\Omega)$ be a Sobolev space for $r \in \mathbb{Z}$ for functions defined on a domain $\Omega$. Then for a function $H^r (\Omega) \ni f: \Omega \rightarrow \mathbb{R}$, the Sobolev norm $$ ||f||_{H^r … Read More →