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arXiv · 1908.01141

Rational Elliptic Surfaces and the Trigonometry of Tetrahedra

Daniil Rudenko
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Abstract

We study the trigonometry of non-Euclidean tetrahedra using tools from algebraic geometry. We establish a bijection between non-Euclidean tetrahedra and certain rational elliptic surfaces. We interpret the edge lengths and the dihedral angles of a tetrahedron as values of period maps for the corresponding surface. As a corollary we show that the cross-ratio of the exponents of the solid angles of a tetrahedron is equal to the cross-ratio of the exponents of the perimeters of its faces. The Regge symmetries of a tetrahedron are related to the action of the Weyl group $W(D_6)$ on the Picard lattice of the corresponding surface.

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Daniil Rudenko. 2019-08-03. Rational Elliptic Surfaces and the Trigonometry of Tetrahedra. https://arxiv.org/abs/1908.01141

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