Uniformly elliptic operator
= Uniformly elliptic operator
= Uniformly elliptic
{synonym}
= Uniform ellipticity
{synonym}
A second-order operator with coefficient matrix $A(x)=(a^{ij}(x))$ is uniformly elliptic when some $\lambda>0$ satisfies $a^{ij}(x)\xi_i\xi_j\geq\lambda|\xi|^2$ everywhere.