6-demicubic honeycomb

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6-demicubic honeycomb
(No image)
Type Uniform 6-honeycomb
Family Alternated hypercube honeycomb
Schläfli symbol h{4,3,3,3,3,4}
h{4,3,3,3,31,1}
ht0,6{4,3,3,3,3,4}
Coxeter diagram Template:CDD = Template:CDD
Template:CDD = Template:CDD
Template:CDD
Facets {3,3,3,3,4}
h{4,3,3,3,3}
Vertex figure r{3,3,3,3,4}
Coxeter group B~6 [4,3,3,3,31,1]
D~6 [31,1,3,3,31,1]

The 6-demicubic honeycomb or demihexeractic honeycomb is a uniform space-filling tessellation (or honeycomb) in Euclidean 6-space. It is constructed as an alternation of the regular 6-cube honeycomb.

It is composed of two different types of facets. The 6-cubes become alternated into 6-demicubes h{4,3,3,3,3} and the alternated vertices create 6-orthoplex {3,3,3,3,4} facets.

D6 lattice

The vertex arrangement of the 6-demicubic honeycomb is the D6 lattice.[1] The 60 vertices of the rectified 6-orthoplex vertex figure of the 6-demicubic honeycomb reflect the kissing number 60 of this lattice.[2] The best known is 72, from the E6 lattice and the 222 honeycomb.

The DTemplate:Sup sub lattice (also called DTemplate:Sup sub) can be constructed by the union of two D6 lattices. This packing is only a lattice for even dimensions. The kissing number is 25=32 (2n-1 for n<8, 240 for n=8, and 2n(n-1) for n>8).[3]

Template:CDDTemplate:CDD

The DTemplate:Sup sub lattice (also called DTemplate:Sup sub and CTemplate:Sup sub) can be constructed by the union of all four 6-demicubic lattices:[4] It is also the 6-dimensional body centered cubic, the union of two 6-cube honeycombs in dual positions.

Template:CDDTemplate:CDDTemplate:CDDTemplate:CDD = Template:CDDTemplate:CDD.

The kissing number of the D6* lattice is 12 (2n for n≥5).[5] and its Voronoi tessellation is a trirectified 6-cubic honeycomb, Template:CDD, containing all birectified 6-orthoplex Voronoi cell, Template:CDD.[6]

Symmetry constructions

There are three uniform construction symmetries of this tessellation. Each symmetry can be represented by arrangements of different colors on the 64 6-demicube facets around each vertex.

Coxeter group Schläfli symbol Coxeter-Dynkin diagram Vertex figure
Symmetry
Facets/verf
B~6 = [31,1,3,3,3,4]
= [1+,4,3,3,3,3,4]
h{4,3,3,3,3,4} Template:CDD = Template:CDD Template:CDD
[3,3,3,4]
64: 6-demicube
12: 6-orthoplex
D~6 = [31,1,3,31,1]
= [1+,4,3,3,31,1]
h{4,3,3,3,31,1} Template:CDD = Template:CDD Template:CDD
[33,1,1]
32+32: 6-demicube
12: 6-orthoplex
½C~6 = [[(4,3,3,3,4,2+)]] ht0,6{4,3,3,3,3,4} Template:CDD 32+16+16: 6-demicube
12: 6-orthoplex

This honeycomb is one of 41 uniform honeycombs constructed by the D~6 Coxeter group, all but 6 repeated in other families by extended symmetry, seen in the graph symmetry of rings in the Coxeter–Dynkin diagrams. The 41 permutations are listed with its highest extended symmetry, and related B~6 and C~6 constructions:

D6 honeycombs
Extended
symmetry
Extended
diagram
Order Honeycombs
[31,1,3,3,31,1] Template:CDD ×1 Template:CDD, Template:CDD
[[31,1,3,3,31,1]] Template:CDD ×2 Template:CDD, Template:CDD, Template:CDD, Template:CDD
<[31,1,3,3,31,1]>
↔ [31,1,3,3,3,4]
Template:CDD
Template:CDD
×2 Template:CDD, Template:CDD, Template:CDD, Template:CDD, Template:CDD, Template:CDD, Template:CDD, Template:CDD,

Template:CDD, Template:CDD, Template:CDD, Template:CDD, Template:CDD, Template:CDD, Template:CDD, Template:CDD

<2[31,1,3,3,31,1]>
↔ [4,3,3,3,3,4]
Template:CDD
Template:CDD
×4 Template:CDD,Template:CDD,

Template:CDD,Template:CDD,

Template:CDD, Template:CDD, Template:CDD, Template:CDD, Template:CDD, Template:CDD, Template:CDD, Template:CDD

[<2[31,1,3,3,31,1]>]
↔ [[4,3,3,3,3,4]]
Template:CDD
Template:CDD
×8 Template:CDD, Template:CDD, Template:CDD,

Template:CDD, Template:CDD, Template:CDD, Template:CDD

See also

Notes

Template:Reflist

  • 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, Template:ISBN [1]
    • (Paper 24) H.S.M. Coxeter, Regular and Semi-Regular Polytopes III, [Math. Zeit. 200 (1988) 3-45]
  • Template:Cite book
Template:Navbar-collapsible
Space Family A~n1 C~n1 B~n1 D~n1 G~2 / F~4 / E~n1
E2 Uniform tiling 0[3] δ3 3 3 Hexagonal
E3 Uniform convex honeycomb 0[4] δ4 4 4
E4 Uniform 4-honeycomb 0[5] δ5 5 5 24-cell honeycomb
E5 Uniform 5-honeycomb 0[6] δ6 6 6
E6 Uniform 6-honeycomb 0[7] δ7 7 7 222
E7 Uniform 7-honeycomb 0[8] δ8 8 8 133331
E8 Uniform 8-honeycomb 0[9] δ9 9 9 152251521
E9 Uniform 9-honeycomb 0[10] δ10 10 10
E10 Uniform 10-honeycomb 0[11] δ11 11 11
En-1 Uniform (n-1)-honeycomb 0[n] δn n n 1k22k1k21
  1. Template:Cite web
  2. Sphere packings, lattices, and groups, by John Horton Conway, Neil James Alexander Sloane, Eiichi Bannai [2]
  3. Conway (1998), p. 119
  4. Template:Cite web
  5. Conway (1998), p. 120
  6. Conway (1998), p. 466