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arXiv · 1502.01779

The Number of Holes in the Union of Translates of a Convex Set in Three Dimensions

Boris Aronov·Otfried Cheong·Michael Gene Dobbins·Xavier Goaoc
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Abstract

We show that the union of $n$ translates of a convex body in $\mathbb{R}^3$ can have $\Theta(n^3)$ holes in the worst case, where a hole in a set $X$ is a connected component of $\mathbb{R}^3 \setminus X$. This refutes a 20-year-old conjecture. As a consequence, we also obtain improved lower bounds on the complexity of motion planning problems and of Voronoi diagrams with convex distance functions.

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Boris Aronov, Otfried Cheong, Michael Gene Dobbins, Xavier Goaoc. 2015-02-06. The Number of Holes in the Union of Translates of a Convex Set in Three Dimensions. https://doi.org/10.1007/s00454-016-9820-4

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