User:Tomruen/Gosset semiregular polytope

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Thorold Gosset's family of semiregular polytopes include:

  1. (E3) triangular prism: -121 (2 Triangles and 3 square faces)
  2. (E4) rectified 5-cell: 021, Tetroctahedric (5 tetrahedra and 5 octahedra cells)
  3. (E5) demipenteract: 121, 5-ic semiregular figure (16 5-cell and 10 16-cell facets)
  4. E6 polytope: 221, 6-ic semiregular figure (72 5-simplex and 27 5-orthoplex facets)
  5. E7 polytope: 321, 7-ic semiregular figure (567 6-simplex and 126 6-orthoplex facets)
  6. E8 polytope: 421, 8-ic semiregular figure (17280 7-simplex and 2160 7-orthoplex facets)
  7. E8 lattice: 521, 9-ic semiregular check (∞ 8-simplex and ∞ 8-orthoplex facets)

Each is constructed from (n-1)-simplex and (n-1)-orthoplex facets, each has a vertex figure as the previous one.

The list ends as an infinite tessellation (space-filling honeycomb) in 8-space.

[edit] Elements

Gosset semiregular figures
n-ic Graph Names
Symbol
Coxeter-Dynkin
Facets Elements
(n-1)-simplex (n-1)-orthoplex Vertices
(0-faces)
Edges
(1-faces)
Faces
(2-faces)
Cells
(3-faces)
(4-faces) (5-faces) (6-faces) (7-faces)
3-ic Triangular prism
-121
Image:CDW_dot.pngImage:CDW_3b.pngImage:CDW_ring.pngImage:CDW_2.pngImage:CDW_ring.png
2 triangles
3 squares
6 9 5          
4-ic Rectified 5-cell
021
Image:CD dot.pngImage:CD 3b.pngImage:CD dot.pngImage:CD 3b.pngImage:CD_downbranch-10.png
5 tetrahedron
5 octahedron
10 30 30 10        
5-ic demipenteract
121
Image:CD dot.pngImage:CD 3b.pngImage:CD dot.pngImage:CD 3b.pngImage:CD_downbranch-00.pngImage:CD 3b.pngImage:CD ring.png
16 5-cell
10 16-cell
16 80 160 120 26      
6-ic E6 polytope
221
Image:CD dot.pngImage:CD 3b.pngImage:CD dot.pngImage:CD 3b.pngImage:CD_downbranch-00.pngImage:CD 3b.pngImage:CD dot.pngImage:CD 3b.pngImage:CD ring.png
72 5-simplexes
27 5-orthoplexes
27 216 720 1080 648 99    
7-ic E7 polytope
321
Image:CD dot.pngImage:CD 3b.pngImage:CD dot.pngImage:CD 3b.pngImage:CD_downbranch-00.pngImage:CD 3b.pngImage:CD dot.pngImage:CD 3b.pngImage:CD dot.pngImage:CD 3b.pngImage:CD ring.png
576 6-simplexes
126 6-orthoplexes
56 756 4032 10080 12096 6048 702  
8-ic E8 polytope
421
Image:CD dot.pngImage:CD 3b.pngImage:CD dot.pngImage:CD 3b.pngImage:CD_downbranch-00.pngImage:CD 3b.pngImage:CD dot.pngImage:CD 3b.pngImage:CD dot.pngImage:CD 3b.pngImage:CD dot.pngImage:CD 3b.pngImage:CD ring.png
17280 7-simplexes
2160 7-orthoplexes
240 6720 60480 241920 483840 483840 206360 19440
9-ic E8 lattice
521
Image:CD dot.pngImage:CD 3b.pngImage:CD dot.pngImage:CD 3b.pngImage:CD_downbranch-00.pngImage:CD 3b.pngImage:CD dot.pngImage:CD 3b.pngImage:CD dot.pngImage:CD 3b.pngImage:CD dot.pngImage:CD 3b.pngImage:CD dot.pngImage:CD 3b.pngImage:CD ring.png
∞ 8-simplexes
∞ 8-orthoplexes

[edit] References

  • T. Gosset: On the Regular and Semi-Regular Figures in Space of n Dimensions, Messenger of Mathematics, Macmillan, 1900
  • 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
  • G.Blind and R.Blind, "The semi-regular polyhedra", Commentari Mathematici Helvetici 66 (1991) 150--154