Truncated 7-demicube
Cantic 7-cube

D7 Coxeter plane projection
Type uniform 7-polytope
Schläfli symbol t{3,34,1}
h2{4,3,3,3,3,3}
Coxeter diagram
6-faces 142
5-faces 1428
4-faces 5656
Cells 11760
Faces 13440
Edges 7392
Vertices 1344
Vertex figure ( )v{ }x{3,3,3}
Coxeter groups D7, [34,1,1]
Properties convex

In seven-dimensional geometry, a cantic 7-cube or truncated 7-demicube as a uniform 7-polytope, being a truncation of the 7-demicube.

A uniform 7-polytope is vertex-transitive and constructed from uniform 6-polytope facets, and can be represented a coxeter diagram with ringed nodes representing active mirrors. A demihypercube is an alternation of a hypercube.

Its 3-dimensional analogue would be a truncated tetrahedron (truncated 3-demicube), and Coxeter diagram or as a cantic cube.

Alternate names

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  • Truncated demihepteract
  • Truncated hemihepteract (thesa) (Jonathan Bowers)[1]

Cartesian coordinates

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The Cartesian coordinates for the 1344 vertices of a truncated 7-demicube centered at the origin and edge length 62 are coordinate permutations:

(±1,±1,±3,±3,±3,±3,±3)

with an odd number of plus signs.

Images

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It can be visualized as a 2-dimensional orthogonal projections, for example the a D7 Coxeter plane, containing 12-gonal symmetry. Most visualizations in symmetric projections will contain overlapping vertices, so the colors of the vertices are changed based on how many vertices are at each projective position, here shown with red color for no overlaps.

orthographic projections
Coxeter
plane
B7 D7 D6
Graph      
Dihedral
symmetry
[14/2] [12] [10]
Coxeter plane D5 D4 D3
Graph      
Dihedral
symmetry
[8] [6] [4]
Coxeter
plane
A5 A3
Graph    
Dihedral
symmetry
[6] [4]
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Dimensional family of cantic n-cubes
n 3 4 5 6 7 8
Symmetry
[1+,4,3n-2]
[1+,4,3]
= [3,3]
[1+,4,32]
= [3,31,1]
[1+,4,33]
= [3,32,1]
[1+,4,34]
= [3,33,1]
[1+,4,35]
= [3,34,1]
[1+,4,36]
= [3,35,1]
Cantic
figure
           
Coxeter      
=    
       
=      
         
=        
           
=          
             
=            
               
=              
Schläfli h2{4,3} h2{4,32} h2{4,33} h2{4,34} h2{4,35} h2{4,36}

There are 95 uniform polytopes with D6 symmetry, 63 are shared by the B6 symmetry, and 32 are unique:

D7 polytopes
 
t0(141)
 
t0,1(141)
 
t0,2(141)
 
t0,3(141)
 
t0,4(141)
 
t0,5(141)
 
t0,1,2(141)
 
t0,1,3(141)
 
t0,1,4(141)
 
t0,1,5(141)
 
t0,2,3(141)
 
t0,2,4(141)
 
t0,2,5(141)
 
t0,3,4(141)
 
t0,3,5(141)
 
t0,4,5(141)
 
t0,1,2,3(141)
 
t0,1,2,4(141)
 
t0,1,2,5(141)
 
t0,1,3,4(141)
 
t0,1,3,5(141)
 
t0,1,4,5(141)
 
t0,2,3,4(141)
 
t0,2,3,5(141)
 
t0,2,4,5(141)
 
t0,3,4,5(141)
 
t0,1,2,3,4(141)
 
t0,1,2,3,5(141)
 
t0,1,2,4,5(141)
 
t0,1,3,4,5(141)
 
t0,2,3,4,5(141)
 
t0,1,2,3,4,5(141)

Notes

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  1. ^ Klitzing, (x3x3o *b3o3o3o3o - thesa)

References

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  • 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, ISBN 978-0-471-01003-6 [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.
  • Klitzing, Richard. "7D uniform polytopes (polyexa) x3x3o *b3o3o3o3o – thesa".
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Family An Bn I2(p) / Dn E6 / E7 / E8 / F4 / G2 Hn
Regular polygon Triangle Square p-gon Hexagon Pentagon
Uniform polyhedron Tetrahedron OctahedronCube Demicube DodecahedronIcosahedron
Uniform polychoron Pentachoron 16-cellTesseract Demitesseract 24-cell 120-cell600-cell
Uniform 5-polytope 5-simplex 5-orthoplex5-cube 5-demicube
Uniform 6-polytope 6-simplex 6-orthoplex6-cube 6-demicube 122221
Uniform 7-polytope 7-simplex 7-orthoplex7-cube 7-demicube 132231321
Uniform 8-polytope 8-simplex 8-orthoplex8-cube 8-demicube 142241421
Uniform 9-polytope 9-simplex 9-orthoplex9-cube 9-demicube
Uniform 10-polytope 10-simplex 10-orthoplex10-cube 10-demicube
Uniform n-polytope n-simplex n-orthoplexn-cube n-demicube 1k22k1k21 n-pentagonal polytope
Topics: Polytope familiesRegular polytopeList of regular polytopes and compounds