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arXiv · 1201.4708

Sobolev spaces and Lagrange interpolation

Bogdan Bojarski
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Abstract

In this short paper the discussion of the pointwise characterization of functions $f$ in the Sobolev space $W^{m,p}(\R^n)$ given in the recent paper (Bojarski) is supplemented in \SS1 by a direct, essentially geometric, proof of the novel inequality (for $m>1$), appearing in Bojarski apparently for the first time, and involving the use of the $m$-th difference of the function $f$. Moreover in \SS2 some additional comments to the text in Bojarski are given and a natural class of Sobolev spaces in domains $G$ in $\R^n$ is defined. \SS3 contains some final remarks.

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Bogdan Bojarski. 2012-01-23. Sobolev spaces and Lagrange interpolation. https://arxiv.org/abs/1201.4708

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