Metric based up-scaling

Houman Owhadi; Lei Zhang

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Metric based up-scaling

Houman Owhadi·Lei Zhang

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Abstract

We consider divergence form elliptic operators in dimension $n\geq 2$ with $L^\infty$ coefficients. Although solutions of these operators are only H\"{o}lder continuous, we show that they are differentiable ($C^{1,\alpha}$) with respect to harmonic coordinates. It follows that numerical homogenization can be extended to situations where the medium has no ergodicity at small scales and is characterized by a continuum of scales by transferring a new metric in addition to traditional averaged (homogenized) quantities from subgrid scales into computational scales and error bounds can be given. This numerical homogenization method can also be used as a compression tool for differential operators.

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Houman Owhadi, Lei Zhang. 2005-05-11. Metric based up-scaling. https://arxiv.org/abs/math/0505223

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