7-demicube

Last updated
Demihepteract
(7-demicube)
Demihepteract ortho petrie.svg
Petrie polygon projection
TypeUniform 7-polytope
Family demihypercube
Coxeter symbol 141
Schläfli symbol {3,34,1} = h{4,35}
s{21,1,1,1,1,1}
Coxeter diagrams CDel nodes 10ru.pngCDel split2.pngCDel node.pngCDel 3.pngCDel node.pngCDel 3.pngCDel node.pngCDel 3.pngCDel node.pngCDel 3.pngCDel node.png = CDel node h1.pngCDel 4.pngCDel node.pngCDel 3.pngCDel node.pngCDel 3.pngCDel node.pngCDel 3.pngCDel node.pngCDel 3.pngCDel node.pngCDel 3.pngCDel node.png

CDel node h.pngCDel 2x.pngCDel node h.pngCDel 4.pngCDel node.pngCDel 3.pngCDel node.pngCDel 3.pngCDel node.pngCDel 3.pngCDel node.pngCDel 3.pngCDel node.png
CDel node h.pngCDel 2x.pngCDel node h.pngCDel 2x.pngCDel node h.pngCDel 4.pngCDel node.pngCDel 3.pngCDel node.pngCDel 3.pngCDel node.pngCDel 3.pngCDel node.png
CDel node h.pngCDel 2x.pngCDel node h.pngCDel 2x.pngCDel node h.pngCDel 2x.pngCDel node h.pngCDel 4.pngCDel node.pngCDel 3.pngCDel node.pngCDel 3.pngCDel node.png
CDel node h.pngCDel 2x.pngCDel node h.pngCDel 2x.pngCDel node h.pngCDel 2x.pngCDel node h.pngCDel 2x.pngCDel node h.pngCDel 4.pngCDel node.pngCDel 3.pngCDel node.png
CDel node h.pngCDel 2x.pngCDel node h.pngCDel 2x.pngCDel node h.pngCDel 2x.pngCDel node h.pngCDel 2x.pngCDel node h.pngCDel 2x.pngCDel node h.pngCDel 4.pngCDel node.png
CDel node h.pngCDel 2x.pngCDel node h.pngCDel 2x.pngCDel node h.pngCDel 2x.pngCDel node h.pngCDel 2x.pngCDel node h.pngCDel 2x.pngCDel node h.pngCDel 2x.pngCDel node h.png

6-faces7814 {31,3,1} Demihexeract ortho petrie.svg
64 {35} 6-simplex t0.svg
5-faces53284 {31,2,1} Demipenteract graph ortho.svg
448 {34} 5-simplex t0.svg
4-faces1624280 {31,1,1} 4-orthoplex.svg
1344 {33} 4-simplex t0.svg
Cells2800560 {31,0,1} 3-simplex t0.svg
2240 {3,3} 3-simplex t0.svg
Faces2240 {3} 2-simplex t0.svg
Edges672
Vertices64
Vertex figure Rectified 6-simplex
6-simplex t1.svg
Symmetry group D7, [34,1,1] = [1+,4,35]
[26]+
Dual?
Properties convex

In geometry, a demihepteract or 7-demicube is a uniform 7-polytope, constructed from the 7-hypercube (hepteract) with alternated vertices removed. It is part of a dimensionally infinite family of uniform polytopes called demihypercubes.

Contents

E. L. Elte identified it in 1912 as a semiregular polytope, labeling it as HM7 for a 7-dimensional half measure polytope.

Coxeter named this polytope as 141 from its Coxeter diagram, with a ring on one of the 1-length branches, CDel node 1.pngCDel 3.pngCDel node.pngCDel split1.pngCDel nodes.pngCDel 3a.pngCDel nodea.pngCDel 3a.pngCDel nodea.pngCDel 3a.pngCDel nodea.png and Schläfli symbol or {3,34,1}.

Cartesian coordinates

Cartesian coordinates for the vertices of a demihepteract centered at the origin are alternate halves of the hepteract:

(±1,±1,±1,±1,±1,±1,±1)

with an odd number of plus signs.

Images

orthographic projections
Coxeter
plane
B7D7D6
Graph 7-demicube t0 B7.svg 7-demicube t0 D7.svg 7-demicube t0 D6.svg
Dihedral
symmetry
[14/2][12][10]
Coxeter planeD5D4D3
Graph 7-demicube t0 D5.svg 7-demicube t0 D4.svg 7-demicube t0 D3.svg
Dihedral
symmetry
[8][6][4]
Coxeter
plane
A5A3
Graph 7-demicube t0 A5.svg 7-demicube t0 A3.svg
Dihedral
symmetry
[6][4]

As a configuration

This configuration matrix represents the 7-demicube. The rows and columns correspond to vertices, edges, faces, cells, 4-faces, 5-faces and 6-faces. The diagonal numbers say how many of each element occur in the whole 7-demicube. The nondiagonal numbers say how many of the column's element occur in or at the row's element. [1] [2]

The diagonal f-vector numbers are derived through the Wythoff construction, dividing the full group order of a subgroup order by removing one mirror at a time. [3]

D7CDel nodea 1.pngCDel 3a.pngCDel branch.pngCDel 3a.pngCDel nodea.pngCDel 3a.pngCDel nodea.pngCDel 3a.pngCDel nodea.pngCDel 3a.pngCDel nodea.png k-face fkf0f1f2f3f4f5f6 k-figures notes
A6CDel nodea x.pngCDel 2.pngCDel branch.pngCDel 3a.pngCDel nodea.pngCDel 3a.pngCDel nodea.pngCDel 3a.pngCDel nodea.pngCDel 3a.pngCDel nodea.png( )f064211053514035105214277 041 D7/A6 = 64*7!/7! = 64
A4A1A1CDel nodea 1.pngCDel 2.pngCDel nodes x0.pngCDel 2.pngCDel nodea.pngCDel 3a.pngCDel nodea.pngCDel 3a.pngCDel nodea.pngCDel 3a.pngCDel nodea.png{ }f12672105201020101052 { }×{3,3,3} D7/A4A1A1 = 64*7!/5!/2/2 = 672
A3A2CDel nodea 1.pngCDel 3a.pngCDel nodes 0x.pngCDel 2.pngCDel nodea x.pngCDel 2.pngCDel nodea.pngCDel 3a.pngCDel nodea.pngCDel 3a.pngCDel nodea.png 100 f233224014466441 {3,3}v( ) D7/A3A2 = 64*7!/4!/3! = 2240
A3A3CDel nodea 1.pngCDel 3a.pngCDel branch.pngCDel 2.pngCDel nodea x.pngCDel 2.pngCDel nodea.pngCDel 3a.pngCDel nodea.pngCDel 3a.pngCDel nodea.png 101 f3464560*406040 {3,3} D7/A3A3 = 64*7!/4!/4! = 560
A3A2CDel nodea 1.pngCDel 3a.pngCDel nodes 0x.pngCDel 3a.pngCDel nodea.pngCDel 2.pngCDel nodea x.pngCDel 2.pngCDel nodea.pngCDel 3a.pngCDel nodea.png 110 464*2240133331 {3}v( ) D7/A3A2 = 64*7!/4!/3! = 2240
D4A2CDel nodea 1.pngCDel 3a.pngCDel branch.pngCDel 3a.pngCDel nodea.pngCDel 2.pngCDel nodea x.pngCDel 2.pngCDel nodea.pngCDel 3a.pngCDel nodea.png 111 f48243288280*3030 {3} D7/D4A2 = 64*7!/8/4!/2 = 280
A4A1CDel nodea 1.pngCDel 3a.pngCDel nodes 0x.pngCDel 3a.pngCDel nodea.pngCDel 3a.pngCDel nodea.pngCDel 2.pngCDel nodea x.pngCDel 2.pngCDel nodea.png 120 5101005*13441221 { }v( ) D7/A4A1 = 64*7!/5!/2 = 1344
D5A1CDel nodea 1.pngCDel 3a.pngCDel branch.pngCDel 3a.pngCDel nodea.pngCDel 3a.pngCDel nodea.pngCDel 2.pngCDel nodea x.pngCDel 2.pngCDel nodea.png 121 f516801604080101684*20{ }D7/D5A1 = 64*7!/16/5!/2 = 84
A5CDel nodea 1.pngCDel 3a.pngCDel nodes 0x.pngCDel 3a.pngCDel nodea.pngCDel 3a.pngCDel nodea.pngCDel 3a.pngCDel nodea.pngCDel 2.pngCDel nodea x.png 130 6152001506*44811D7/A5 = 64*7!/6! = 448
D6CDel nodea 1.pngCDel 3a.pngCDel branch.pngCDel 3a.pngCDel nodea.pngCDel 3a.pngCDel nodea.pngCDel 3a.pngCDel nodea.pngCDel 2.pngCDel nodea x.png 131 f63224064016048060192123214*( )D7/D6 = 64*7!/32/6! = 14
A6CDel nodea 1.pngCDel 3a.pngCDel nodes 0x.pngCDel 3a.pngCDel nodea.pngCDel 3a.pngCDel nodea.pngCDel 3a.pngCDel nodea.pngCDel 3a.pngCDel nodea.png 140 7213503502107*64D7/A6 = 64*7!/7! = 64

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

D7 polytopes
7-demicube t0 D7.svg
t0(141)
7-demicube t01 D7.svg
t0,1(141)
7-demicube t02 D7.svg
t0,2(141)
7-demicube t03 D7.svg
t0,3(141)
7-demicube t04 D7.svg
t0,4(141)
7-demicube t05 D7.svg
t0,5(141)
7-demicube t012 D7.svg
t0,1,2(141)
7-demicube t013 D7.svg
t0,1,3(141)
7-demicube t014 D7.svg
t0,1,4(141)
7-demicube t015 D7.svg
t0,1,5(141)
7-demicube t023 D7.svg
t0,2,3(141)
7-demicube t024 D7.svg
t0,2,4(141)
7-demicube t025 D7.svg
t0,2,5(141)
7-demicube t034 D7.svg
t0,3,4(141)
7-demicube t035 D7.svg
t0,3,5(141)
7-demicube t045 D7.svg
t0,4,5(141)
7-demicube t0123 D7.svg
t0,1,2,3(141)
7-demicube t0124 D7.svg
t0,1,2,4(141)
7-demicube t0125 D7.svg
t0,1,2,5(141)
7-demicube t0134 D7.svg
t0,1,3,4(141)
7-demicube t0135 D7.svg
t0,1,3,5(141)
7-demicube t0145 D7.svg
t0,1,4,5(141)
7-demicube t0234 D7.svg
t0,2,3,4(141)
7-demicube t0235 D7.svg
t0,2,3,5(141)
7-demicube t0245 D7.svg
t0,2,4,5(141)
7-demicube t0345 D7.svg
t0,3,4,5(141)
7-demicube t01234 D7.svg
t0,1,2,3,4(141)
7-demicube t01235 D7.svg
t0,1,2,3,5(141)
7-demicube t01245 D7.svg
t0,1,2,4,5(141)
7-demicube t01345 D7.svg
t0,1,3,4,5(141)
7-demicube t02345 D7.svg
t0,2,3,4,5(141)
7-demicube t012345 D7.svg
t0,1,2,3,4,5(141)

Related Research Articles

In five-dimensional geometry, a 5-cube is a name for a five-dimensional hypercube with 32 vertices, 80 edges, 80 square faces, 40 cubic cells, and 10 tesseract 4-faces.

<span class="mw-page-title-main">5-demicube</span> Regular 5-polytope

In five-dimensional geometry, a demipenteract or 5-demicube is a semiregular 5-polytope, constructed from a 5-hypercube (penteract) with alternated vertices removed.

<span class="mw-page-title-main">6-demicube</span> Uniform 6-polytope

In geometry, a 6-demicube or demihexeract is a uniform 6-polytope, constructed from a 6-cube (hexeract) with alternated vertices removed. It is part of a dimensionally infinite family of uniform polytopes called demihypercubes.

<span class="mw-page-title-main">7-cube</span> 7-dimensional hypercube

In geometry, a 7-cube is a seven-dimensional hypercube with 128 vertices, 448 edges, 672 square faces, 560 cubic cells, 280 tesseract 4-faces, 84 penteract 5-faces, and 14 hexeract 6-faces.

<span class="mw-page-title-main">8-demicube</span>

In geometry, a demiocteract or 8-demicube is a uniform 8-polytope, constructed from the 8-hypercube, octeract, with alternated vertices removed. It is part of a dimensionally infinite family of uniform polytopes called demihypercubes.

<span class="mw-page-title-main">9-demicube</span> Uniform 9-polytope

In geometry, a demienneract or 9-demicube is a uniform 9-polytope, constructed from the 9-cube, with alternated vertices removed. It is part of a dimensionally infinite family of uniform polytopes called demihypercubes.

<span class="mw-page-title-main">8-cube</span> 8-dimensional hypercube

In geometry, an 8-cube is an eight-dimensional hypercube. It has 256 vertices, 1024 edges, 1792 square faces, 1792 cubic cells, 1120 tesseract 4-faces, 448 5-cube 5-faces, 112 6-cube 6-faces, and 16 7-cube 7-faces.

<span class="mw-page-title-main">9-cube</span> 9-dimensional hypercube

In geometry, a 9-cube is a nine-dimensional hypercube with 512 vertices, 2304 edges, 4608 square faces, 5376 cubic cells, 4032 tesseract 4-faces, 2016 5-cube 5-faces, 672 6-cube 6-faces, 144 7-cube 7-faces, and 18 8-cube 8-faces.

In geometry, a 6-simplex is a self-dual regular 6-polytope. It has 7 vertices, 21 edges, 35 triangle faces, 35 tetrahedral cells, 21 5-cell 4-faces, and 7 5-simplex 5-faces. Its dihedral angle is cos−1(1/6), or approximately 80.41°.

<span class="mw-page-title-main">8-orthoplex</span>

In geometry, an 8-orthoplex or 8-cross polytope is a regular 8-polytope with 16 vertices, 112 edges, 448 triangle faces, 1120 tetrahedron cells, 1792 5-cells 4-faces, 1792 5-faces, 1024 6-faces, and 256 7-faces.

<span class="mw-page-title-main">10-cube</span> 10-dimensional hypercube

In geometry, a 10-cube is a ten-dimensional hypercube. It has 1024 vertices, 5120 edges, 11520 square faces, 15360 cubic cells, 13440 tesseract 4-faces, 8064 5-cube 5-faces, 3360 6-cube 6-faces, 960 7-cube 7-faces, 180 8-cube 8-faces, and 20 9-cube 9-faces.

<span class="mw-page-title-main">Rectified 5-simplexes</span>

In five-dimensional geometry, a rectified 5-simplex is a convex uniform 5-polytope, being a rectification of the regular 5-simplex.

<span class="mw-page-title-main">10-demicube</span>

In geometry, a 10-demicube or demidekeract is a uniform 10-polytope, constructed from the 10-cube with alternated vertices removed. It is part of a dimensionally infinite family of uniform polytopes called demihypercubes.

<span class="mw-page-title-main">Runcic 5-cubes</span> Concept in geometry

In six-dimensional geometry, a runcic 5-cube or is a convex uniform 5-polytope. There are 2 runcic forms for the 5-cube. Runcic 5-cubes have half the vertices of runcinated 5-cubes.

<span class="mw-page-title-main">Cantic 7-cube</span>

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

<span class="mw-page-title-main">Steric 6-cubes</span>

In six-dimensional geometry, a steric 6-cube is a convex uniform 6-polytope. There are unique 4 steric forms of the 6-cube.

<span class="mw-page-title-main">Pentic 6-cubes</span>

In six-dimensional geometry, a pentic 6-cube is a convex uniform 6-polytope.

<span class="mw-page-title-main">Runcic 7-cubes</span>

In seven-dimensional geometry, a runcic 7-cube is a convex uniform 7-polytope, related to the uniform 7-demicube. There are 2 unique forms.

<span class="mw-page-title-main">Hexic 7-cubes</span>

In seven-dimensional geometry, a hexic 7-cube is a convex uniform 7-polytope, constructed from the uniform 7-demicube. There are 16 unique forms.

<span class="mw-page-title-main">Steric 7-cubes</span>

In seven-dimensional geometry, a stericated 7-cube is a convex uniform 7-polytope, being a runcination of the uniform 7-demicube. There are 4 unique runcinations for the 7-demicube including truncation and cantellation.

References

  1. Coxeter, Regular Polytopes, sec 1.8 Configurations
  2. Coxeter, Complex Regular Polytopes, p.117
  3. Klitzing, Richard. "x3o3o *b3o3o3o - hax".
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