On the volume of spherical Lambert cube
Abstract
The calculation of volumes of polyhedra in the three-dimensional Euclidean, spherical and hyperbolic spaces is very old and difficult problem. In particular, an elementary formula for volume of non-euclidean simplex is still unknown. One of the simplest polyhedra is the Lambert cube Q(α,β,γ). By definition, Q(α,β,γ) is a combinatorial cube, with dihedral angles α,β and γ assigned to the three mutually non-coplanar edges and right angles to the remaining. The hyperbolic volume of Lambert cube was found by Ruth Kellerhals (1989) in terms of the Lobachevsky function (x). In the present paper the spherical volume of Q(α,β,γ) is defined in the terms of the function δ(α,θ) which can be considered as a spherical analog of the Lobachevsky function (α,θ)=(α + θ) - (α - θ)
Turn this paper into a full lesson
ArcXiv compiles a staged curriculum from this paper: 8-12 lessons across beginner → advanced, synthesised section guides, visuals, flashcards, a quiz, exercises, and on-demand deep dives per section. Grounded in the abstract, never invented.