Quantitative Runge Approximation and Inverse Problems

Angkana Rüland; Mikko Salo

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arXiv · 1708.06307

Quantitative Runge Approximation and Inverse Problems

Angkana Rüland·Mikko Salo

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Abstract

In this short note we provide a quantitative version of the classical Runge approximation property for second order elliptic operators. This relies on quantitative unique continuation results and duality arguments. We show that these estimates are essentially optimal. As a model application we provide a new proof of the result from \cite{F07}, \cite{AK12} on stability for the Calder\'on problem with local data.

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Angkana Rüland, Mikko Salo. 2017-08-21. Quantitative Runge Approximation and Inverse Problems. https://arxiv.org/abs/1708.06307

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