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24-cell

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{

"text": "The 24-cell is a unique object in four-dimensional geometry. It is classified as a convex regular 4-polytope. This means it is a four-dimensional shape where every part is identical. In three dimensions, we have Platonic solids like the cube. The 24-cell is the four-dimensional analogue of these solids.

24-cell
24-cell

It is often called the icositetrachoron or the octaplex. Other names include the icosatetrahedroid, the octacube, the hyper-diamond, or the polyoctahedron. It is defined by its Schläfli symbol, {3,4,3}. This symbol describes how its components fit together in higher space.\n\nTo understand its structure, we must look at its constituent parts. The 24-cell is composed of 24 octahedral cells. An octahedron is a three-dimensional shape with eight triangular faces.

Octahedron
Octahedron

These cells connect to form a complex boundary. The shape contains 96 triangular faces and 96 edges. It also has 24 vertices, which are its corner points. At each vertex, exactly six octahedral cells meet. At each edge, three cells meet. The vertex figure, which describes the arrangement around a vertex, is a cube.

24-cell-6 ring edge center perspective
24-cell-6 ring edge center perspective

\n\nThe 24-cell possesses several rare geometric properties. It is a self-dual polytope. This means its dual shape is identical to itself. Like the 5-cell, it maintains this symmetry. It is also one of only two convex regular 4-polytopes where the edge length equals the radius. The other is the tesseract. Furthermore, the 24-cell is highly inclusive of other geometries. It incorporates the geometries of almost every convex regular polytope in the first four dimensions. It includes all regular polytopes made of triangles and squares, except for the 5-cell. It does not, however, include pentagonal polytopes.\n\nIn the sequence of six convex regular 4-polytopes, the 24-cell holds the fourth position. These shapes can be ordered by their hypervolume, or four-dimensional content, for a given radius. They also nest

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🖼️ Images & Media (16)
File:Octahedron.png
Octahedron.png
File:F4 roots by 24-cell duals.svg
F4 roots by 24-cell duals.svg
File:Binary tetrahedral group elements.png
Binary tetrahedral group elements.png
File:Icositetrachoronic tetracomb.png
Icositetrachoronic tetracomb.png
File:24-cell.gif
24-cell.gif
File:24-cell-orig.gif
24-cell-orig.gif
File:Hopf band wikipedia.png
Hopf band wikipedia.png
File:Regular_star_figure_4(6,1).svg
Regular_star_figure_4(6,1).svg
File:Regular_star_figure_4(3,1).svg
Regular_star_figure_4(3,1).svg
File:Regular_star_figure_2(6,1).svg
Regular_star_figure_2(6,1).svg
File:Regular_polygon_24.svg
Regular_polygon_24.svg
File:Regular_star_figure_12(2,1).svg
Regular_star_figure_12(2,1).svg

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