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arXiv · 2201.01974

Characterizations of diffusion matrices in homogenization of elliptic equations in nondivergence-form

Xiaoqin Guo·Timo Sprekeler·Hung V. Tran
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Abstract

We characterize diffusion matrices that yield a $L^{\infty}$ convergence rate of $\mathcal{O}(\varepsilon^2)$ in the theory of periodic homogenization of linear elliptic equations in nondivergence-form. Such type-$\varepsilon^2$ diffusion matrices are of particular interest as the optimal rate of convergence in the generic case is only $\mathcal{O}(\varepsilon)$. First, we provide a new class of type-$\varepsilon^2$ diffusion matrices, confirming a conjecture posed in [15]. Then, we give a complete characterization of diagonal diffusion matrices in two dimensions and a systematic study in higher dimensions.

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Xiaoqin Guo, Timo Sprekeler, Hung V. Tran. 2022-01-06. Characterizations of diffusion matrices in homogenization of elliptic equations in nondivergence-form. https://doi.org/10.1007/s00526-024-02884-5

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