Optimal monohedral tilings of hyperbolic surfaces

Leonardo Di Giosia; Jahangir Habib; Jack Hirsch; Lea Kenigsberg; Kevin Li; Dylanger Pittman; Jackson Petty; Christopher Xue; Weitao Zhu

arXiv · 1911.04476

Optimal monohedral tilings of hyperbolic surfaces

Leonardo Di Giosia·Jahangir Habib·Jack Hirsch·Lea Kenigsberg·Kevin Li·Dylanger Pittman·Jackson Petty·Christopher Xue·Weitao Zhu

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Abstract

The hexagon is the least-perimeter tile in the Euclidean plane for any given area. On hyperbolic surfaces, this "isoperimetric" problem differs for every given area, as solutions do not scale. Cox conjectured that a regular $k$-gonal tile with 120-degree angles is isoperimetric. For area $\pi/3$, the regular heptagon has 120-degree angles and therefore tiles many hyperbolic surfaces. For other areas, we show the existence of many tiles but provide no conjectured optima. On closed hyperbolic surfaces, we verify via a reduction argument using cutting and pasting transformations and convex hulls that the regular $7$-gon is the optimal $n$-gonal tile of area $\pi/3$ for $3\leq n \leq 10$. However, for $n>10$, it is difficult to rule out non-convex $n$-gons that tile irregularly.

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BibTeX RIS

Leonardo Di Giosia, Jahangir Habib, Jack Hirsch, Lea Kenigsberg, Kevin Li, Dylanger Pittman, Jackson Petty, Christopher Xue, Weitao Zhu. 2019-11-11. Optimal monohedral tilings of hyperbolic surfaces. https://arxiv.org/abs/1911.04476

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