On planar Sobolev $L^m_p$-extension domains

Pavel Shvartsman; Nahum Zobin

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arXiv · 1410.3100

On planar Sobolev $L^m_p$-extension domains

Pavel Shvartsman·Nahum Zobin

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Abstract

For each $m\ge 1$ and $p>2$ we characterize bounded simply connected Sobolev $L^m_p$-extension domains $Ω\subset R^2$. Our criterion is expressed in terms of certain intrinsic subhyperbolic metrics in $Ω$. Its proof is based on a series of results related to the existence of special chains of squares joining given points $x$ and $y$ in $Ω$. An important geometrical ingredient for obtaining these results is a new "Square Separation Theorem". It states that under certain natural assumptions on the relative positions of a point $x$ and a square $S\subsetΩ$ there exists a similar square $Q\subsetΩ$ which touches $S$ and has the property that $x$ and $S$ belong to distinct connected components of $Ω\setminus Q$.

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BibTeX RIS

Pavel Shvartsman, Nahum Zobin. 2015-07-22. On planar Sobolev $L^m_p$-extension domains. https://arxiv.org/abs/1410.3100

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