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arXiv · 2606.29839

Planar sets with large visible parts

Tuomas Orponen
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Abstract

I construct a compact subset of the plane whose visible parts are $\tfrac{3}{2}$-dimensional in all directions. This disproves the visibility conjecture. The value $\tfrac{3}{2}$ cannot be increased, as shown in recent collaboration with A. Rutar.

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Tuomas Orponen. 2026-06-29. Planar sets with large visible parts. https://arxiv.org/abs/2606.29839

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