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arXiv · 1710.05070

Cube is a strict local maximizer for the illumination number

Galyna Livshyts·Konstantin Tikhomirov
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Abstract

It was conjectured by Levi, Hadwiger, Gohberg and Markus that the boundary of any convex body in ${\mathbb R}^n$ can be illuminated by at most $2^n$ light sources, and, moreover, $2^n-1$ light sources suffice unless the body is a parallelotope. We show that if a convex body is close to the cube in the Banach-Mazur metric, and it is not a parallelotope, then indeed $2^n-1$ light sources suffice to illuminate its boundary. Equivalently, any convex body sufficiently close to the cube, but not isometric to it, can be covered by $2^n-1$ smaller homothetic copies of itself.

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Galyna Livshyts, Konstantin Tikhomirov. 2017-10-13. Cube is a strict local maximizer for the illumination number. https://arxiv.org/abs/1710.05070

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