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arXiv · 2105.05467

Strong $BV$-extension and $W^{1,1}$-extension domains

Miguel García-Bravo·Tapio Rajala
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Abstract

We show that a bounded domain in a Euclidean space is a $W^{1,1}$-extension domain if and only if it is a strong $BV$-extension domain. In the planar case, bounded and strong $BV$-extension domains are shown to be exactly those $BV$-extension domains for which the set $\partial\Omega \setminus \bigcup_{i} \overline{\Omega}_i$ is purely $1$-unrectifiable, where $\Omega_i$ are the open connected components of $\mathbb{R}^2\setminus\overline{\Omega}$.

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Miguel García-Bravo, Tapio Rajala. 2021-05-12. Strong $BV$-extension and $W^{1,1}$-extension domains. https://arxiv.org/abs/2105.05467

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