Biggest Little Polyhedron
Biggest Little Polyhedron
A polyhedron has vertices. The greatest distance between vertices is 1. What is the maximum volume of the polyhedron? This is known as the biggest little polyhedron problem.
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For four vertices, the solution is trivially the regular tetrahedron.
Five vertices require an equilateral triangle and a perpendicular unit line; this was solved in 1976[1].
Six vertices require a more complex solution, which was solved to four digits of accuracy in 2003[2, 3].
The author found exact solutions for 6, 7, 8, 9, 10, 11, and 16 points[4, 5]. This Demonstration contains those solutions, as well as the best known solutions up to 128 points. Oleg Vlasii improved many of these values.
Details
Details
The unit-rod polyhedron shows a rod between all vertex pairs a unit distance apart.
The unit-star picture builds polygons from half-unit rods meeting at a vertex.
The unit-length graph shows how vertices a unit distance apart are connected.
The planar vertex map puts the vertices on a sphere, then unrolls the sphere into a planar form.
In the supported triangles image, all vertices of a blue triangle (with brown number) are at distance 1 from an opposing vertex with a matching green number.
The Initialization section contains various programs that may be able to improve some of the solutions.
References
References
[1] B. Kind and P. Kleinschmidt, "On the Maximal Volume of Convex Bodies with Few Vertices," Journal of Combinatorial Theory, Series A, 21(1) 1976 pp. 124–128. doi:10.1016/0097-3165(76)90056-X.
[2] A. Klein and M. Wessler, "The Largest Small -dimensional Polytope with Vertices," Journal of Combinatorial Theory, Series A, 102(2), 2003 pp. 401–409. doi:10.1016/S0097-3165(03)00054-2.
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[3] A. Klein and M. Wessler, "A Correction to 'The Largest Small -dimensional Polytope with Vertices,'" Journal of Combinatorial Theory, Series A, 112(1), 2005 pp. 173–174. doi:10.1016/j.jcta.2005.06.001.
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[4] E. Pegg Jr. "Biggest Little Polyhedra" from Wolfram Community—A Wolfram Web Resource. (Oct 28, 2015) community.wolfram.com/groups/-/m/t/463699.
[5] E. Pegg Jr. "Biggest Little Polyhedron—New Solutions in Combinatorial Geometry" from Wolfram Blog—A Wolfram Web Resource. (May 20, 2015) blog.wolfram.com/2015/05/20/biggest-little-polyhedronnew-solutions-in-combinatorial-geometry.
External Links
External Links
Permanent Citation
Permanent Citation
Ed Pegg Jr
"Biggest Little Polyhedron"
http://demonstrations.wolfram.com/BiggestLittlePolyhedron/
Wolfram Demonstrations Project
Published: November 3, 2015