Uniform 1 k2 polytope

{{Short description|Uniform polytope}}

{{DISPLAYTITLE:Uniform 1 k2 polytope}}

In geometry, 1k2 polytope is a uniform polytope in n-dimensions (n = k+4) constructed from the En Coxeter group. The family was named by their Coxeter symbol 1k2 by its bifurcating Coxeter-Dynkin diagram, with a single ring on the end of the 1-node sequence. It can be named by an extended Schläfli symbol {3,3k,2}.

Family members

The family starts uniquely as 6-polytopes, but can be extended backwards to include the 5-demicube (demipenteract) in 5-dimensions, and the 4-simplex (5-cell) in 4-dimensions.

Each polytope is constructed from 1k-1,2 and (n-1)-demicube facets. Each has a vertex figure of a {31,n-2,2} polytope is a birectified n-simplex, t2{3n}.

The sequence ends with k=6 (n=10), as an infinite tessellation of 9-dimensional hyperbolic space.

The complete family of 1k2 polytope polytopes are:

  1. 5-cell: 102, (5 tetrahedral cells)
  2. 112 polytope, (16 5-cell, and 10 16-cell facets)
  3. 122 polytope, (54 demipenteract facets)
  4. 132 polytope, (56 122 and 126 demihexeract facets)
  5. 142 polytope, (240 132 and 2160 demihepteract facets)
  6. 152 honeycomb, tessellates Euclidean 8-space (∞ 142 and ∞ demiocteract facets)
  7. 162 honeycomb, tessellates hyperbolic 9-space (∞ 152 and ∞ demienneract facets)

Elements

class="wikitable"

|+

Gosset 1k2 figures

rowspan=2|n

!rowspan=2|1k2

!rowspan=2| Petrie
polygon

projection

!rowspan=2| Name
Coxeter-Dynkin
diagram

!colspan=2|Facets

!colspan=8|Elements

1k-1,2

!(n-1)-demicube

! Vertices

! Edges

! Faces

! Cells

! 4-faces

! 5-faces

! 6-faces

! 7-faces

align=center

|4

|102

|80px

|120
{{CDD|nodea|3a|nodea|3a|branch_01l}}

| --

|5
110
40px

| 5

| 10

| 10
40px

| 5
40px

align=center

|5

|112

|80px

|121
{{CDD|nodea|3a|nodea|3a|branch_01lr|3a|nodea}}

|16
120
40px

|10
111
40px

|16

|80

|160
40px

|120
40px

|26
25px25px

align=center

|6

|122

|80px

|122
{{CDD|nodea|3a|nodea|3a|branch_01lr|3a|nodea|3a|nodea}}

|27
112
40px

|27
121
40px

|72

|720

|2160
40px

|2160
40px

|702
25px25px

|54
25px

align=center

|7

|132

|80px

|132
{{CDD|nodea|3a|nodea|3a|branch_01lr|3a|nodea|3a|nodea|3a|nodea}}

|56
122
40px

|126
131
40px

|576

|10080

|40320
40px

|50400
40px

|23688
25px25px

|4284
25px25px

|182
25px25px

align=center

|8

|142

|80px

|142
{{CDD|nodea|3a|nodea|3a|branch_01lr|3a|nodea|3a|nodea|3a|nodea|3a|nodea}}

|240
132
40px

|2160
141
40px

|17280

|483840

|2419200
40px

|3628800
40px

|2298240
25px25px

|725760
25px25px

|106080
25px25px25px

|2400
25px25px

align=center

|9

|152

|

|152
{{CDD|nodea|3a|nodea|3a|branch_01lr|3a|nodea|3a|nodea|3a|nodea|3a|nodea|3a|nodea}}
(8-space tessellation)

|∞
142
40px

|∞
151
40px

|colspan=8|∞

align=center

|10

|162

|

|162
{{CDD|nodea|3a|nodea|3a|branch_01lr|3a|nodea|3a|nodea|3a|nodea|3a|nodea|3a|nodea|3a|nodea}}
(9-space hyperbolic tessellation)

|∞
152

|∞
161
40px

|colspan=8|∞

See also

References

  • Alicia Boole Stott Geometrical deduction of semiregular from regular polytopes and space fillings, Verhandelingen of the Koninklijke academy van Wetenschappen width unit Amsterdam, Eerste Sectie 11,1, Amsterdam, 1910
  • Stott, A. B. "Geometrical Deduction of Semiregular from Regular Polytopes and Space Fillings." Verhandelingen der Koninklijke Akad. Wetenschappen Amsterdam 11, 3-24, 1910.
  • Alicia Boole Stott, "Geometrical deduction of semiregular from regular polytopes and space fillings," Verhandelingen der Koninklijke Akademie van Wetenschappen te Amsterdam, (eerste sectie), Vol. 11, No. 1, pp. 1–24 plus 3 plates, 1910.
  • Stott, A. B. 1910. "Geometrical Deduction of Semiregular from Regular Polytopes and Space Fillings." Verhandelingen der Koninklijke Akad. Wetenschappen Amsterdam
  • Schoute, P. H., Analytical treatment of the polytopes regularly derived from the regular polytopes, Ver. der Koninklijke Akad. van Wetenschappen te Amsterdam (eerstie sectie), vol 11.5, 1913.
  • H. S. M. Coxeter: Regular and Semi-Regular Polytopes, Part I, Mathematische Zeitschrift, Springer, Berlin, 1940
  • N.W. Johnson: The Theory of Uniform Polytopes and Honeycombs, Ph.D. Dissertation, University of Toronto, 1966
  • H.S.M. Coxeter: Regular and Semi-Regular Polytopes, Part II, Mathematische Zeitschrift, Springer, Berlin, 1985
  • H.S.M. Coxeter: Regular and Semi-Regular Polytopes, Part III, Mathematische Zeitschrift, Springer, Berlin, 1988