6-cube

{{Short description|6-dimensional hypercube}}

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!bgcolor=#e7dcc3 colspan=2|6-cube
Hexeract

bgcolor=#ffffff align=center colspan=2|280px
Orthogonal projection
inside Petrie polygon
Orange vertices are doubled, and the center yellow has 4 vertices
bgcolor=#e7dcc3|TypeRegular 6-polytope
bgcolor=#e7dcc3|Familyhypercube
bgcolor=#e7dcc3|Schläfli symbol{4,34}
bgcolor=#e7dcc3|Coxeter diagram{{CDD|node_1|4|node|3|node|3|node|3|node|3|node}}
bgcolor=#e7dcc3|5-faces12 {4,3,3,3} 25px
bgcolor=#e7dcc3|4-faces60 {4,3,3} 25px
bgcolor=#e7dcc3|Cells160 {4,3} 25px
bgcolor=#e7dcc3|Faces240 {4} 25px
bgcolor=#e7dcc3|Edges192
bgcolor=#e7dcc3|Vertices64
bgcolor=#e7dcc3|Vertex figure5-simplex
bgcolor=#e7dcc3|Petrie polygondodecagon
bgcolor=#e7dcc3|Coxeter groupB6, [34,4]
bgcolor=#e7dcc3|Dual6-orthoplex 25px
bgcolor=#e7dcc3|Propertiesconvex, Hanner polytope

In geometry, a 6-cube is a six-dimensional hypercube with 64 vertices, 192 edges, 240 square faces, 160 cubic cells, 60 tesseract 4-faces, and 12 5-cube 5-faces.

It has Schläfli symbol {4,34}, being composed of 3 5-cubes around each 4-face. It can be called a hexeract, a portmanteau of tesseract (the 4-cube) with hex for six (dimensions) in Greek. It can also be called a regular dodeca-6-tope or dodecapeton, being a 6-dimensional polytope constructed from 12 regular facets.

Related polytopes

It is a part of an infinite family of polytopes, called hypercubes. The dual of a 6-cube can be called a 6-orthoplex, and is a part of the infinite family of cross-polytopes. It is composed of various 5-cubes, at perpendicular angles on the u-axis, forming coordinates (x,y,z,w,v,u).{{Cite web|url=https://www.researchgate.net/publication/361688598|title=A New Six-Dimensional Hyper-Chaotic System}}{{Cite journal|url=https://www.sciencedirect.com/science/article/pii/S0747717188800105|title=An improved projection operation for cylindrical algebraic decomposition of three-dimensional space - ScienceDirect|journal=Journal of Symbolic Computation |date=February 1988 |volume=5 |issue=1 |pages=141–161 |doi=10.1016/S0747-7171(88)80010-5 |last1=McCallum |first1=Scott }}

Applying an alternation operation, deleting alternating vertices of the 6-cube, creates another uniform polytope, called a 6-demicube, (part of an infinite family called demihypercubes), which has 12 5-demicube and 32 5-simplex facets.

As a configuration

This configuration matrix represents the 6-cube. The rows and columns correspond to vertices, edges, faces, cells, 4-faces and 5-faces. The diagonal numbers say how many of each element occur in the whole 6-cube. The nondiagonal numbers say how many of the column's element occur in or at the row's element.Coxeter, Regular Polytopes, sec 1.8 ConfigurationsCoxeter, Complex Regular Polytopes, p.117

\begin{bmatrix}\begin{matrix}64 & 6 & 15 & 20 & 15 & 6 \\ 2 & 192 & 5 & 10 & 10 & 5 \\ 4 & 4 & 240 & 4 & 6 & 4 \\ 8 & 12 & 6 & 160 & 3 & 3 \\ 16 & 32 & 24 & 8 & 60 & 2 \\ 32 & 80 & 80 & 40 & 10 & 12 \end{matrix}\end{bmatrix}

Cartesian coordinates

Cartesian coordinates for the vertices of a 6-cube centered at the origin and edge length 2 are

: (±1,±1,±1,±1,±1,±1)

while the interior of the same consists of all points (x0, x1, x2, x3, x4, x5) with −1 < xi < 1.

Construction

There are three Coxeter groups associated with the 6-cube, one regular, with the C6 or [4,3,3,3,3] Coxeter group, and a half symmetry (D6) or [33,1,1] Coxeter group. The lowest symmetry construction is based on hyperrectangles or proprisms, cartesian products of lower dimensional hypercubes.

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!Name

!Coxeter

!Schläfli

!Symmetry

!Order

align=center

!Regular 6-cube

|{{CDD|node_1|4|node|3|node|3|node|3|node|3|node}}
{{CDD|node_f1|3|node|3|node|3|node|3|node|4|node}}

|{4,3,3,3,3}

|[4,3,3,3,3]

46080
align=center

!Quasiregular 6-cube

|{{CDD|node_f1|3|node|3|node|3|node|split1|nodes}}

|

|[3,3,3,31,1]

23040
align=center

!rowspan=10|hyperrectangle

|{{CDD|node_1|4|node|3|node|3|node|3|node|2|node_1}}

{4,3,3,3}×{}[4,3,3,3,2]7680
align=center

|{{CDD|node_1|4|node|3|node|3|node|2|node_1|4|node}}

{4,3,3}×{4}[4,3,3,2,4]3072
align=center

|{{CDD|node_1|4|node|3|node|2|node_1|4|node|3|node}}

{4,3}2[4,3,2,4,3]2304
align=center

|{{CDD|node_1|4|node|3|node|3|node|2|node_1|2|node_1}}

{4,3,3}×{}2[4,3,3,2,2]1536
align=center

|{{CDD|node_1|4|node|3|node|2|node_1|4|node|2|node_1}}

{4,3}×{4}×{}[4,3,2,4,2]768
align=center

|{{CDD|node_1|4|node|2|node_1|4|node|2|node_1|4|node}}

{4}3[4,2,4,2,4]512
align=center

|{{CDD|node_1|4|node|3|node|2|node_1|2|node_1|2|node_1}}

{4,3}×{}3[4,3,2,2,2]384
align=center

|{{CDD|node_1|4|node|2|node_1|4|node|2|node_1|2|node_1}}

{4}2×{}2[4,2,4,2,2]256
align=center

|{{CDD|node_1|4|node|2|node_1|2|node_1|2|node_1|2|node_1}}

{4}×{}4[4,2,2,2,2]128
align=center

|{{CDD|node_1|2|node_1|2|node_1|2|node_1|2|node_1|2|node_1}}

|{}6

|[2,2,2,2,2]

64

Projections

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|+ orthographic projections

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!Coxeter plane

!B6

!B5

!B4

align=center

!Graph

|150px

|150px

|150px

align=center

!Dihedral symmetry

|[12]

|[10]

|[8]

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!Coxeter plane

!Other

!B3

!B2

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!Graph

|150px

|150px

|150px

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!Dihedral symmetry

|[2]

|[6]

|[4]

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!Coxeter plane

!

!A5

!A3

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!Graph

|

|150px

|150px

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!Dihedral symmetry

|

|[6]

|[4]

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|colspan=2 valign=top align=center|3D Projections

280px
6-cube 6D simple rotation through 2Pi with 6D perspective projection to 3D.

|280px
6-cube quasicrystal structure orthographically projected
to 3D using the golden ratio.

280px
A 3D perspective projection of a hexeract undergoing a triple rotation about the X-W1, Y-W2 and Z-W3 orthogonal planes.

Related polytopes

The 64 vertices of a 6-cube also represent a regular skew 4-polytope {4,3,4 | 4}. Its net can be seen as a 4×4×4 matrix of 64 cubes, a periodic subset of the cubic honeycomb, {4,3,4}, in 3-dimensions. It has 192 edges, and 192 square faces. Opposite faces fold together into a 4-cycle. Each fold direction adds 1 dimension, raising it into 6-space.

The 6-cube is 6th in a series of hypercube:

{{Hypercube polytopes}}

This polytope is one of 63 uniform 6-polytopes generated from the B6 Coxeter plane, including the regular 6-cube or 6-orthoplex.

{{Hexeract family}}

References

  • Coxeter, H.S.M. Regular Polytopes, (3rd edition, 1973), Dover edition, {{ISBN|0-486-61480-8}} p. 296, Table I (iii): Regular Polytopes, three regular polytopes in n-dimensions (n>=5)
  • {{KlitzingPolytopes|polypeta.htm|6D uniform polytopes (polypeta)|o3o3o3o3o4x - ax}}