Homogenization for non-self-adjoint locally periodic elliptic operators

Abstract: We study the homogenization problem for matrix strongly elliptic operators on $L_2(\mathbb R^d)^n$ of the form $\mathcal A^\varepsilon=-\operatorname{div}A(x,x/\varepsilon)\nabla$. The function $A$ is Lipschitz in the first variable and periodic in the second. We do not require that $A^*=A$, so $\mathcal A^\varepsilon$ need not be self-adjoint. In this paper, we provide, for small $\varepsilon$, two terms in the uniform approximation for $(\mathcal A^\varepsilon-\mu)^{-1}$ and a first term in the uniform approximation for $\nabla(\mathcal A^\varepsilon-\mu)^{-1}$. Primary attention is paid to proving sharp-order bounds on the errors of the approximations.