D4.10 (EntityTopic, 15)

From Hi.gher. Space

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{{STS Shape
{{STS Shape
| dim=4
| dim=4
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| elements=132, 592, 636, 176
| extra={{STS Polytope
| extra={{STS Polytope
}}}}
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'''D4.10''' is a [[bilbirothawroid]] with a pair of antipodal tetrahedra surrounded by 6 [[bilunabirotunda]]e (J91) each, with 4 tridiminished icosahedra filling up the gaps between the J91's around each tetrahedron. There are also 8 J92's, 4 on the two identical hemispheres of the polytope, which are oriented in dual orientation to each other.
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'''D4.10''' is a [[bilbirothawroid]] with a pair of antipodal [[tetrahedra]] surrounded by 6 [[bilunabirotunda]]e (J91) each, with 4 [[tridiminished icosahedra]] filling up the gaps between the J91's around each tetrahedron. There are also 8 [[J92]]'s, 4 on the two identical hemispheres of the polytope, which are oriented in dual orientation to each other.
It is related to [[D4.11]] via a slight modification of its lace tower.
It is related to [[D4.11]] via a slight modification of its lace tower.
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== Elements ==
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{{TODO|Split faces, edges and vertices into unique positions.}}
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;Cells
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*16 [[tetrahedra]] (2 + 6 + 8)
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*24 [[square pyramid]]s
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*32 [[octahedra]] (24 + 8)
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*8 [[tridiminished icosahedra]]
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*8 [[triangular cupola]]e
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*24 [[pentagonal antiprism]]s
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*12 J91's
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*8 J92's
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;Faces
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*464 [[triangle]]s
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*48 [[square]]s
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*72 [[pentagon]]s
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*8 [[hexagon]]s
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*636 edges
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*176 vertices
== Lace tower ==
== Lace tower ==
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</pre></blockquote>
</pre></blockquote>
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==Software models==
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== Software models ==
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*[[Polyview]] [http://hddb.teamikaria.com/dl/ZATKWKW47QY9PS9PPSHVWYF7TE.def .def file]
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* Polyview [http://hddb.teamikaria.com/dl/ZATKWKW47QY9PS9PPSHVWYF7TE.def .def file]
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*[[Stella4D]] [http://hddb.teamikaria.com/dl/QS746WG1QG36CR3A40JJPQA5RP.off .off file]
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* Stella4D [http://hddb.teamikaria.com/dl/QS746WG1QG36CR3A40JJPQA5RP.off .off file]
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Latest revision as of 21:28, 18 March 2014

D4.10 is a bilbirothawroid with a pair of antipodal tetrahedra surrounded by 6 bilunabirotundae (J91) each, with 4 tridiminished icosahedra filling up the gaps between the J91's around each tetrahedron. There are also 8 J92's, 4 on the two identical hemispheres of the polytope, which are oriented in dual orientation to each other.

It is related to D4.11 via a slight modification of its lace tower.

Elements

TODO: Split faces, edges and vertices into unique positions.

Cells
Faces
  • 636 edges
  • 176 vertices

Lace tower

          x3o3o   // tetrahedron
          f3o3x   // 4 tetrahedra touching vertices of previous one
          o3x3f   // midpoints of J91's
          f3x3x   // square faces of J91's
          x3o3F   // octahedra above J63's
          x3F3o   // opposite edge of J91's
          f3x3f   // f3x vertices of 8 J92's (this is the midpoint)
          o3F3x
          F3o3x
          x3x3f
          f3x3o
          x3o3f
          o3o3x

As you can see, there are two antipodal tetrahedra. EDIT 3: Also, there are no lacing edges between f3x3x and x3o3F, so that part of the tower may be better written as:

           ...
           o3x3f
          /  f3x3x
      x3o3F    |   
         |    x3F3o
         | f3x3f |
         o3F3x   |
         |    F3o3x
        x3x3f   /
           f3x3o
          ...

Projections

Centered on one of the antipodal tetrahedra:

(image)

Same 4D viewpoint, with J92 cells highlighted:

(image)

Side-view, showing that it nearly has 16-cell symmetry:

(image)

Coordinates

apecs<1/√2, 1/√2, 1/√2> ~ <-(2*phi+3)/√2>
apecs<phi^2/√2, phi^2/√2, 1/(phi*√2)> ~ <-(phi+3)/√2>
apecs<(phi+2)/√2, phi/√2, -phi/√2> ~ <-(phi+2)/√2>
apecs<1/(phi*√2), phi^2/√2, (phi^2+2)/√2> ~ <-phi^2/√2>                                
apecs<-(phi+2)/√2, -phi/√2, -(phi+2)/√2> ~ <-phi/√2>
apecs<(2*phi+3)/√2, 1/√2, 1/√2> ~ <-1/√2>
apacs<0, phi*√2, phi^2*√2> ~ <0>
apecs<1/√2, 1/√2, -(2*phi+3)/√2> ~ <1/√2>
apecs<phi/√2, (phi+2)/√2, (phi+2)/√2> ~ <phi/√2>
apecs<1/(phi*√2), phi^2/√2, -(phi+3)/√2> ~ <phi^2/√2>
apecs<(phi+2)/√2, phi/√2, phi/√2> ~ <(phi+2)/√2>
apecs<1/(phi*√2), phi^2/√2, -phi^2/√2> ~ <(phi+3)/√2>
apecs<1/√2, 1/√2, -1/√2> ~ <(2*phi+3)/√2>

Software models