Abstract
Criteria for approximability of functions by solutions of homogeneous second order elliptic equations (with constant complex coefficients) in the norms of the Whitney \(C^1\)-spaces on compact sets in \(\mathbb {R}^2\) are obtained in terms of the respective \(C^1\)-capacities. It is proved that the mentioned \(C^1\)-capacities are comparable to the classic C-analytic capacity, and so have a proper geometric measure characterization.
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P.V. Paramonov: Supported by the Russian Science Foundation (Grant No. 17-11-01064).
X. Tolsa: Partially supported by 2017-SGR-0395 (Catalonia) and MTM-2016-77635-P (MICINN, Spain).
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Paramonov, P.V., Tolsa, X. On \(C^1\)-approximability of functions by solutions of second order elliptic equations on plane compact sets and C-analytic capacity. Anal.Math.Phys. 9, 1133–1161 (2019). https://doi.org/10.1007/s13324-018-0275-z
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DOI: https://doi.org/10.1007/s13324-018-0275-z