Truncated 7-cubes
In seven-dimensional geometry, a truncated 7-cube is a convex uniform 7-polytope, being a truncation of the regular 7-cube.
There are 6 truncations for the 7-cube. Vertices of the truncated 7-cube are located as pairs on the edge of the 7-cube. Vertices of the bitruncated 7-cube are located on the square faces of the 7-cube. Vertices of the tritruncated 7-cube are located inside the cubic cells of the 7-cube. The final three truncations are best expressed relative to the 7-orthoplex.
Truncated 7-cube
[edit | edit source]| Truncated 7-cube | |
|---|---|
| Type | uniform 7-polytope |
| Schläfli symbol | t{4,35} |
| Coxeter-Dynkin diagrams | File:CDel node 1.pngFile:CDel 4.pngFile:CDel node 1.pngFile:CDel 3.pngFile:CDel node.pngFile:CDel 3.pngFile:CDel node.pngFile:CDel 3.pngFile:CDel node.pngFile:CDel 3.pngFile:CDel node.pngFile:CDel 3.pngFile:CDel node.png |
| 6-faces | |
| 5-faces | |
| 4-faces | |
| Cells | |
| Faces | |
| Edges | 3136 |
| Vertices | 896 |
| Vertex figure | Elongated 5-simplex pyramid |
| Coxeter groups | B7, [35,4] |
| Properties | convex |
Alternate names
[edit | edit source]- Truncated hepteract (Jonathan Bowers)[1]
Coordinates
[edit | edit source]Cartesian coordinates for the vertices of a truncated 7-cube, centered at the origin, are all sign and coordinate permutations of
- (1,1+√2,1+√2,1+√2,1+√2,1+√2,1+√2)
Images
[edit | edit source]| Coxeter plane | B7 / A6 | B6 / D7 | B5 / D6 / A4 |
|---|---|---|---|
| Graph | File:7-cube t01.svg | File:7-cube t01 B6.svg | File:7-cube t01 B5.svg |
| Dihedral symmetry | [14] | [12] | [10] |
| Coxeter plane | B4 / D5 | B3 / D4 / A2 | B2 / D3 |
| Graph | File:7-cube t01 B4.svg | File:7-cube t01 B3.svg | File:7-cube t01 B2.svg |
| Dihedral symmetry | [8] | [6] | [4] |
| Coxeter plane | A5 | A3 | |
| Graph | File:7-cube t01 A5.svg | File:7-cube t01 A3.svg | |
| Dihedral symmetry | [6] | [4] |
Related polytopes
[edit | edit source]The truncated 7-cube, is sixth in a sequence of truncated hypercubes:
Bitruncated 7-cube
[edit | edit source]| Bitruncated 7-cube | |
|---|---|
| Type | uniform 7-polytope |
| Schläfli symbol | 2t{4,35} |
| Coxeter-Dynkin diagrams | File:CDel node.pngFile:CDel 4.pngFile:CDel node 1.pngFile:CDel 3.pngFile:CDel node 1.pngFile:CDel 3.pngFile:CDel node.pngFile:CDel 3.pngFile:CDel node.pngFile:CDel 3.pngFile:CDel node.pngFile:CDel 3.pngFile:CDel node.png File:CDel nodes 11.pngFile:CDel split2.pngFile:CDel node 1.pngFile:CDel 3.pngFile:CDel node.pngFile:CDel 3.pngFile:CDel node.pngFile:CDel 3.pngFile:CDel node.pngFile:CDel 3.pngFile:CDel node.png |
| 6-faces | |
| 5-faces | |
| 4-faces | |
| Cells | |
| Faces | |
| Edges | 9408 |
| Vertices | 2688 |
| Vertex figure | { }v{3,3,3} |
| Coxeter groups | B7, [35,4] D7, [34,1,1] |
| Properties | convex |
Alternate names
[edit | edit source]- Bitruncated hepteract (Jonathan Bowers)[2]
Coordinates
[edit | edit source]Cartesian coordinates for the vertices of a bitruncated 7-cube, centered at the origin, are all sign and coordinate permutations of
- (±2,±2,±2,±2,±2,±1,0)
Images
[edit | edit source]| Coxeter plane | B7 / A6 | B6 / D7 | B5 / D6 / A4 |
|---|---|---|---|
| Graph | File:7-cube t12.svg | File:7-cube t12 B6.svg | File:7-cube t12 B5.svg |
| Dihedral symmetry | [14] | [12] | [10] |
| Coxeter plane | B4 / D5 | B3 / D4 / A2 | B2 / D3 |
| Graph | File:7-cube t12 B4.svg | File:7-cube t12 B3.svg | File:7-cube t12 B2.svg |
| Dihedral symmetry | [8] | [6] | [4] |
| Coxeter plane | A5 | A3 | |
| Graph | File:7-cube t12 A5.svg | File:7-cube t12 A3.svg | |
| Dihedral symmetry | [6] | [4] |
Related polytopes
[edit | edit source]The bitruncated 7-cube is fifth in a sequence of bitruncated hypercubes:
Tritruncated 7-cube
[edit | edit source]| Tritruncated 7-cube | |
|---|---|
| Type | uniform 7-polytope |
| Schläfli symbol | 3t{4,35} |
| Coxeter-Dynkin diagrams | File:CDel node.pngFile:CDel 4.pngFile:CDel node.pngFile:CDel 3.pngFile:CDel node 1.pngFile:CDel 3.pngFile:CDel node 1.pngFile:CDel 3.pngFile:CDel node.pngFile:CDel 3.pngFile:CDel node.pngFile:CDel 3.pngFile:CDel node.png File:CDel nodes.pngFile:CDel split2.pngFile:CDel node 1.pngFile:CDel 3.pngFile:CDel node 1.pngFile:CDel 3.pngFile:CDel node.pngFile:CDel 3.pngFile:CDel node.pngFile:CDel 3.pngFile:CDel node.png |
| 6-faces | |
| 5-faces | |
| 4-faces | |
| Cells | |
| Faces | |
| Edges | 13440 |
| Vertices | 3360 |
| Vertex figure | {4}v{3,3} |
| Coxeter groups | B7, [35,4] D7, [34,1,1] |
| Properties | convex |
Alternate names
[edit | edit source]- Tritruncated hepteract (Jonathan Bowers)[3]
Coordinates
[edit | edit source]Cartesian coordinates for the vertices of a tritruncated 7-cube, centered at the origin, are all sign and coordinate permutations of
- (±2,±2,±2,±2,±1,0,0)
Images
[edit | edit source]| Coxeter plane | B7 / A6 | B6 / D7 | B5 / D6 / A4 |
|---|---|---|---|
| Graph | File:7-cube t23.svg | File:7-cube t23 B6.svg | File:7-cube t23 B5.svg |
| Dihedral symmetry | [14] | [12] | [10] |
| Coxeter plane | B4 / D5 | B3 / D4 / A2 | B2 / D3 |
| Graph | File:7-cube t23 B4.svg | File:7-cube t23 B3.svg | File:7-cube t23 B2.svg |
| Dihedral symmetry | [8] | [6] | [4] |
| Coxeter plane | A5 | A3 | |
| Graph | File:7-cube t23 A5.svg | File:7-cube t23 A3.svg | |
| Dihedral symmetry | [6] | [4] |
Notes
[edit | edit source]References
[edit | edit source]- H.S.M. Coxeter:
- H.S.M. Coxeter, Regular Polytopes, 3rd Edition, Dover New York, 1973
- Kaleidoscopes: Selected Writings of H.S.M. Coxeter, edited by F. Arthur Sherk, Peter McMullen, Anthony C. Thompson, Asia Ivic Weiss, Wiley-Interscience Publication, 1995, Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value). [1]
- (Paper 22) H.S.M. Coxeter, Regular and Semi Regular Polytopes I, [Math. Zeit. 46 (1940) 380-407, MR 2,10]
- (Paper 23) H.S.M. Coxeter, Regular and Semi-Regular Polytopes II, [Math. Zeit. 188 (1985) 559-591]
- (Paper 24) H.S.M. Coxeter, Regular and Semi-Regular Polytopes III, [Math. Zeit. 200 (1988) 3-45]
- Norman Johnson Uniform Polytopes, Manuscript (1991)
- N.W. Johnson: The Theory of Uniform Polytopes and Honeycombs, Ph.D.
- Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value). o3o3o3o3o3x4x - taz, o3o3o3o3x3x4o - botaz, o3o3o3x3x3o4o - totaz