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arXiv · 2301.07429

On volume and surface area of parallel sets. II. Surface measures and (non-)differentiability of the volume

Jan Rataj·Steffen Winter
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Abstract

We prove that at differentiability points $r_0>0$ of the volume function of a compact set $A\subset {\mathbb R}^d$ (associating to $r$ the volume of the $r$-parallel set of $A$), the surface area measures of $r$-parallel sets of $A$ converge weakly to the surface area measure of the $r_0$-parallel set as $r\to r_0$. We further study the question which sets of parallel radii can occur as sets of non-differentiability points of the volume function of some compact set. We provide a full characterization for dimensions $d=1$ and $2$.

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Jan Rataj, Steffen Winter. 2023-01-18. On volume and surface area of parallel sets. II. Surface measures and (non-)differentiability of the volume. https://arxiv.org/abs/2301.07429

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