Cantellated 120-cell explained

In four-dimensional geometry, a cantellated 120-cell is a convex uniform 4-polytope, being a cantellation (a 2nd order truncation) of the regular 120-cell.

There are four degrees of cantellations of the 120-cell including with permutations truncations. Two are expressed relative to the dual 600-cell.

Cantellated 120-cell

bgcolor=#e7dcc3 colspan=2Cantellated 120-cell
TypeUniform 4-polytope
Uniform index37
Coxeter diagram
Cells
Faces4800+3600+720
Edges10800
Vertices3600
Vertex figure
wedge
Schläfli symbolt0,2
Symmetry groupH4, [3,3,5], order 14400
Propertiesconvex

The cantellated 120-cell is a uniform 4-polytope. It is named by its construction as a Cantellation operation applied to the regular 120-cell. It contains 1920 cells, including 120 rhombicosidodecahedra, 1200 triangular prisms, 600 octahedra. Its vertex figure is a wedge, with two rhombicosidodecahedra, two triangular prisms, and one octahedron meeting at each vertex.

Alternative names

Images

Cantitruncated 120-cell

bgcolor=#e7dcc3 colspan=2Cantitruncated 120-cell
TypeUniform 4-polytope
Uniform index42
Schläfli symbolt0,1,2
Coxeter diagram
Cells
Faces9120:
2400+3600+
2400+720
Edges14400
Vertices7200
Vertex figure
sphenoid
Symmetry groupH4, [3,3,5], order 14400
Propertiesconvex
The cantitruncated 120-cell is a uniform polychoron.

This 4-polytope is related to the regular 120-cell. The cantitruncation operation create new truncated tetrahedral cells at the vertices, and triangular prisms at the edges. The original dodecahedron cells are cantitruncated into great rhombicosidodecahedron cells.

The image shows the 4-polytope drawn as a Schlegel diagram which projects the 4-dimensional figure into 3-space, distorting the sizes of the cells. In addition, the decagonal faces are hidden, allowing us to see the elemented projected inside.

Alternative names

Images

Cantellated 600-cell

bgcolor=#e7dcc3 colspan=2Cantellated 600-cell
TypeUniform 4-polytope
Uniform index40
Schläfli symbolt0,2
Coxeter diagram
Cells1440 total:
120 3.5.3.5
600 3.4.3.4
720 4.4.5
Faces8640 total:
(1200+2400)
+3600+1440
Edges10800
Vertices3600
Vertex figure
isosceles triangular prism
Symmetry groupH4, [3,3,5], order 14400
Propertiesconvex
The cantellated 600-cell is a uniform 4-polytope. It has 1440 cells: 120 icosidodecahedra, 600 cuboctahedra, and 720 pentagonal prisms. Its vertex figure is an isosceles triangular prism, defined by one icosidodecahedron, two cuboctahedra, and two pentagonal prisms.

Alternative names

Construction

This 4-polytope has cells at 3 of 4 positions in the fundamental domain, extracted from the Coxeter diagram by removing one node at a time:

NodeOrderCoxeter diagram
CellPicture
0600Cantellated tetrahedron
(Cuboctahedron)
11200None
(Degenerate triangular prism)
 
2720Pentagonal prism
3120Rectified dodecahedron
(Icosidodecahedron)

There are 1440 pentagonal faces between the icosidodecahedra and pentagonal prisms. There are 3600 squares between the cuboctahedra and pentagonal prisms. There are 2400 triangular faces between the icosidodecahedra and cuboctahedra, and 1200 triangular faces between pairs of cuboctahedra.

There are two classes of edges: 3-4-4, 3-4-5: 3600 have two squares and a triangle around it, and 7200 have one triangle, one square, and one pentagon.

Images

Cantitruncated 600-cell

bgcolor=#e7dcc3 colspan=2Cantitruncated 600-cell
TypeUniform 4-polytope
Uniform index45
Coxeter diagram
Cells
Faces8640:
3600+1440+
3600
Edges14400
Vertices7200
Vertex figure
sphenoid
Schläfli symbolt0,1,2
Symmetry groupH4, [3,3,5], order 14400
Propertiesconvex
The cantitruncated 600-cell is a uniform 4-polytope. It is composed of 1440 cells: 120 truncated icosahedra, 720 pentagonal prisms and 600 truncated octahedra. It has 7200 vertices, 14400 edges, and 8640 faces (3600 squares, 1440 pentagons, and 3600 hexagons). It has an irregular tetrahedral vertex figure, filled by one truncated icosahedron, one pentagonal prism and two truncated octahedra.

Alternative names

Images

References

External links

Notes and References

  1. Klitzing, (o3x3o5x - srahi)
  2. Klitzing, (o3x3x5x - grahi)
  3. Klitzing, (x3o3x5o - srix)
  4. Klitzing, (x3x3x5o - grix)