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arXiv · 1804.11033

Areas of spherical polyhedral surfaces with regular faces

Yohji Akama·Bobo Hua·Yanhui Su
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Abstract

For a finite planar graph, it associates with some metric spaces, called (regular) spherical polyhedral surfaces, by replacing faces with regular spherical polygons in the unit sphere and gluing them edge-to-edge. We consider the class of planar graphs which admit spherical polyhedral surfaces with the curvature bounded below by 1 in the sense of Alexandrov, i.e. the total angle at each vertex is at most $2\pi$. We classify all spherical tilings with regular spherical polygons, i.e. total angles at vertices are exactly $2\pi$. We prove that for any graph in this class which does not admit a spherical tiling, the area of the associated spherical polyhedral surface with the curvature bounded below by 1 is at most $4\pi - \epsilon_0$ for some $\epsilon_0 > 0$. That is, we obtain a definite gap between the area of such a surface and that of the unit sphere.

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Yohji Akama, Bobo Hua, Yanhui Su. 2018-04-30. Areas of spherical polyhedral surfaces with regular faces. https://arxiv.org/abs/1804.11033

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