Runcinated tesseracts


Tesseract

Runcinated tesseract
(Runcinated 16-cell)

16-cell

Runcitruncated tesseract
(Runcicantellated 16-cell)

Runcitruncated 16-cell
(Runcicantellated tesseract)

Omnitruncated tesseract
(Omnitruncated 16-cell)
Orthogonal projections in B4 Coxeter plane

In four-dimensional geometry, a runcinated tesseract (or runcinated 16-cell) is a convex uniform 4-polytope, being a runcination (a 3rd order truncation) of the regular tesseract.

There are 4 variations of runcinations of the tesseract including with permutations truncations and cantellations.

Runcinated tesseract

Runcinated tesseract

Schlegel diagram with 16 tetrahedra
Type Uniform 4-polytope
Schläfli symbol t0,3{4,3,3}
Coxeter diagrams
Cells 80 16 3.3.3
32 3.4.4
32 4.4.4
Faces 208 64 {3}
144 {4}
Edges 192
Vertices 64
Vertex figure
Equilateral-triangular antipodium
Symmetry group B4, [3,3,4], order 384
Properties convex
Uniform index 14 15 16

The runcinated tesseract or (small) disprismatotesseractihexadecachoron has 16 tetrahedra, 32 cubes, and 32 triangular prisms. Each vertex is shared by 4 cubes, 3 triangular prisms and one tetrahedron.

Construction

The runcinated tesseract may be constructed by expanding the cells of a tesseract radially, and filling in the gaps with tetrahedra (vertex figures), cubes (face prisms), and triangular prisms (edge figures). The same process applied to a 16-cell also yields the same figure.

Cartesian coordinates

The Cartesian coordinates of the vertices of the runcinated tesseract with edge length 2 are all permutations of:

Images

orthographic projections
Coxeter plane B4 B3 / D4 / A2 B2 / D3
Graph
Dihedral symmetry [8] [6] [4]
Coxeter plane F4 A3
Graph
Dihedral symmetry [12/3] [4]
Schlegel diagrams

Wireframe

Wireframe with 16 tetrahedra.

Wireframe with 32 triangular prisms.

Structure

Eight of the cubical cells are connected to the other 24 cubical cells via all 6 square faces. The other 24 cubical cells are connected to the former 8 cells via only two opposite square faces; the remaining 4 faces are connected to the triangular prisms. The triangular prisms are connected to the tetrahedra via their triangular ==== Dissection====faces.

The runcinated tesseract can be dissected into 2 cubic cupolae and a rhombicuboctahedral prism between them. This dissection can be seen analogous to the 3D rhombicuboctahedron being dissected into two square cupola and a central octagonal prism.


cubic cupola

rhombicuboctahedral prism

Projections

The cube-first orthographic projection of the runcinated tesseract into 3-dimensional space has a (small) rhombicuboctahedral envelope. The images of its cells are laid out within this envelope as follows:

This layout of cells in projection is analogous to the layout of the faces of the (small) rhombicuboctahedron under projection to 2 dimensions. The rhombicuboctahedron is also constructed from the cube or the octahedron in an analogous way to the runcinated tesseract. Hence, the runcinated tesseract may be thought of as the 4-dimensional analogue of the rhombicuboctahedron.

Runcitruncated tesseract

Runcitruncated tesseract

Schlegel diagram
centered on a truncated cube,
with cuboctahedral cells shown
Type Uniform 4-polytope
Schläfli symbol t0,1,3{4,3,3}
Coxeter diagrams
Cells 80 8 3.4.4
16 3.4.3.4
24 4.4.8
32 3.4.4
Faces 368 128 {3}
192 {4}
48 {8}
Edges 480
Vertices 192
Vertex figure
Rectangular pyramid
Symmetry group B4, [3,3,4], order 384
Properties convex
Uniform index 18 19 20

The runcitruncated tesseract, runcicantellated 16-cell, or prismatorhombated hexadecachoron is bounded by 80 cells: 8 truncated cubes, 16 cuboctahedra, 24 octagonal prisms, and 32 triangular prisms.

Construction

The runcitruncated tesseract may be constructed from the truncated tesseract by expanding the truncated cube cells outward radially, and inserting octagonal prisms between them. In the process, the tetrahedra expand into cuboctahedra, and triangular prisms fill in the remaining gaps.

The Cartesian coordinates of the vertices of the runcitruncated tesseract having an edge length of 2 is given by all permutations of:

Projections

In the truncated cube first parallel projection of the runcitruncated tesseract into 3-dimensional space, the projection image is laid out as follows:

Images

orthographic projections
Coxeter plane B4 B3 / D4 / A2 B2 / D3
Graph
Dihedral symmetry [8] [6] [4]
Coxeter plane F4 A3
Graph
Dihedral symmetry [12/3] [4]


Stereographic projection with its 128 blue triangular faces and its 192 green quad faces.

Runcitruncated 16-cell

Runcitruncated 16-cell

Schlegel diagrams centered on
rhombicuboctahedron and truncated tetrahedron
Type Uniform 4-polytope
Schläfli symbol t0,1,3{3,3,4}
Coxeter diagram
Cells 80 8 3.4.4.4
16 3.6.6
24 4.4.4
32 4.4.6
Faces 368 64 {3}
240 {4}
64 {6}
Edges 480
Vertices 192
Vertex figure
Trapezoidal pyramid
Symmetry group B4, [3,3,4], order 384
Properties convex
Uniform index 19 20 21

The runcitruncated 16-cell, runcicantellated tesseract, or prismatorhombated tesseract is bounded by 80 cells: 8 rhombicuboctahedra, 16 truncated tetrahedra, 24 cubes, and 32 hexagonal prisms.

Construction

The runcitruncated 16-cell may be constructed by contracting the small rhombicuboctahedral cells of the cantellated tesseract radially, and filling in the spaces between them with cubes. In the process, the octahedral cells expand into truncated tetrahedra (half of their triangular faces are expanded into hexagons by pulling apart the edges), and the triangular prisms expand into hexagonal prisms (each with its three original square faces joined, as before, to small rhombicuboctahedra, and its three new square faces joined to cubes).

The vertices of a runcitruncated 16-cell having an edge length of 2 is given by all permutations of the following Cartesian coordinates:

Images

orthographic projections
Coxeter plane B4 B3 / D4 / A2 B2 / D3
Graph
Dihedral symmetry [8] [6] [4]
Coxeter plane F4 A3
Graph
Dihedral symmetry [12/3] [4]

Structure

The small rhombicuboctahedral cells are joined via their 6 axial square faces to the cubical cells, and joined via their 12 non-axial square faces to the hexagonal prisms. The cubical cells are joined to the rhombicuboctahedra via 2 opposite faces, and joined to the hexagonal prisms via the remaining 4 faces. The hexagonal prisms are connected to the truncated tetrahedra via their hexagonal faces, and to the rhombicuboctahedra via 3 of their square faces each, and to the cubes via the other 3 square faces. The truncated tetrahedra are joined to the rhombicuboctahedra via their triangular faces, and the hexagonal prisms via their hexagonal faces.

Projections

The following is the layout of the cells of the runcitruncated 16-cell under the parallel projection, small rhombicuboctahedron first, into 3-dimensional space:

This layout of cells is similar to the layout of the faces of the great rhombicuboctahedron under the projection into 2-dimensional space. Hence, the runcitruncated 16-cell may be thought of as one of the 4-dimensional analogues of the great rhombicuboctahedron. The other analogue is the omnitruncated tesseract.

Omnitruncated tesseract

Omnitruncated tesseract

Schlegel diagram,
centered on truncated cuboctahedron,
truncated octahedral cells shown
Type Uniform 4-polytope
Schläfli symbol t0,1,2,3{3,3,4}
Coxeter diagram
Cells 80 8 4.6.8
16 4.6.6
24 4.4.8
32 4.4.6
Faces 464 288 {4}
128 {6}
48 {8}
Edges 768
Vertices 384
Vertex figure
Chiral scalene tetrahedron
Symmetry group B4, [3,3,4], order 384
Properties convex
Uniform index 20 21 22

The omnitruncated tesseract, omnitruncated 16-cell, or great disprismatotesseractihexadecachoron is bounded by 80 cells: 8 truncated cuboctahedra, 16 truncated octahedra, 24 octagonal prisms, and 32 hexagonal prisms.

Construction

The omnitruncated tesseract can be constructed from the cantitruncated tesseract by radially displacing the truncated cuboctahedral cells so that octagonal prisms can be inserted between their octagonal faces. As a result, the triangular prisms expand into hexagonal prisms, and the truncated tetrahedra expand into truncated octahedra.

The Cartesian coordinates of the vertices of an omnitruncated tesseract having an edge length of 2 are given by all permutations of coordinates and sign of:

Structure

The truncated cuboctahedra cells are joined to the octagonal prisms via their octagonal faces, the truncated octahedra via their hexagonal faces, and the hexagonal prisms via their square faces. The octagonal prisms are joined to the hexagonal prisms and the truncated octahedra via their square faces, and the hexagonal prisms are joined to the truncated octahedra via their hexagonal faces.

Projections

In the truncated cuboctahedron first parallel projection of the omnitruncated tesseract into 3 dimensions, the images of its cells are laid out as follows:

This layout of cells in projection is similar to that of the runcitruncated 16-cell, which is analogous to the layout of faces in the octagon-first projection of the truncated cuboctahedron into 2 dimensions. Thus, the omnitruncated tesseract may be thought of as another analogue of the truncated cuboctahedron in 4 dimensions.

Images

orthographic projections
Coxeter plane B4 B3 / D4 / A2 B2 / D3
Graph
Dihedral symmetry [8] [6] [4]
Coxeter plane F4 A3
Graph
Dihedral symmetry [12/3] [4]
Perspective projections

Perspective projection centered on one of the truncated cuboctahedral cells, highlighted in yellow. Six of the surrounding octahedral prisms rendered in blue, and the remaining cells in green. Cells obscured from 4D viewpoint culled for clarity's sake.

Perspective projection centered on one of the truncated octahedral cells, highlighted in yellow. Four of the surrounding hexagonal prisms are shown in blue, with 4 more truncated octahedra on the other side of these prisms also shown in yellow. Cells obscured from 4D viewpoint culled for clarity's sake. Some of the other hexagonal and octagonal prisms may be discerned from this view as well.
Stereographic projections

Centered on truncated cuboctahedron

Centered on truncated octahedron
Net

Omnitruncated tesseract

Dual to omnitruncated tesseract

Full snub tesseract

Vertex figure for the omnisnub tesseract

The full snub tesseract or omnisnub tesseract, defined as an alternation of the omnitruncated tesseract, can not be made uniform, but it can be given Coxeter diagram , and symmetry [4,3,3]+, and constructed from 16 icosahedra, 32 octahedra, 24 square antiprisms, 8 snub cubes and 192 tetrahedra filling the gaps at the deleted vertices. It has 272 cells, 944 faces, 864 edges, and 192 vertices.[1]

Related uniform polytopes

Notes

References

External links

Fundamental convex regular and uniform polytopes in dimensions 2–10
Family An Bn I2(p) / Dn E6 / E7 / E8 / E9 / E10 / F4 / G2 Hn
Regular polygon Triangle Square p-gon Hexagon Pentagon
Uniform polyhedron Tetrahedron OctahedronCube Demicube DodecahedronIcosahedron
Uniform 4-polytope 5-cell 16-cellTesseract Demitesseract 24-cell 120-cell600-cell
Uniform 5-polytope 5-simplex 5-orthoplex5-cube 5-demicube
Uniform 6-polytope 6-simplex 6-orthoplex6-cube 6-demicube 122221
Uniform 7-polytope 7-simplex 7-orthoplex7-cube 7-demicube 132231321
Uniform 8-polytope 8-simplex 8-orthoplex8-cube 8-demicube 142241421
Uniform 9-polytope 9-simplex 9-orthoplex9-cube 9-demicube
Uniform 10-polytope 10-simplex 10-orthoplex10-cube 10-demicube
Uniform n-polytope n-simplex n-orthoplexn-cube n-demicube 1k22k1k21 n-pentagonal polytope
Topics: Polytope familiesRegular polytopeList of regular polytopes and compounds
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