Schauder estimate (source code)

= Schauder estimate
{c}
{wiki=Schauder_estimates}

A Schauder estimate bounds a solution in a Hölder norm two derivatives stronger than the forcing term. For a uniformly elliptic Dirichlet problem with $C^\alpha$ coefficients,
$$
\lVert u\rVert_{C^{2,\alpha}(\overline\Omega)}
\leq C\bigl(\lVert Lu\rVert_{C^\alpha(\overline\Omega)}+\lVert u\rVert_{C^0(\overline\Omega)}\bigr).
$$