User:Tetracube/Uniform polytera

In geometry, a uniform polyteron is a 5-dimensional polytope which is vertex-transitive, and whose hypercells are uniform polychora.

Convex uniform polytera edit

In 5 dimensions and higher, the only regular polytopes are the n-simplex, the n-cross polytope, and the n-hypercube. The hexateron (5-simplex) gives rise to the hexateric family of uniform polytera, while the pentacross (5-cross) and penteract (5-cube) give rise to the penteractic family of uniform polytera.

In addition, there is the family of demihypercubes which in 5D and above is distinct from the hypercube family of uniform polytopes. In 5D, this is the demipenteractic family.

Finally, there are the infinite families of prisms, derived from the prisms and duoprisms of the previous dimensions.

The penteractic family edit

See Uniform_polyteron#The_B5_.5B4.2C3.2C3.2C3.5D_family_.28penteract.2Fpentacross.29

The penteractic family of polytera are given by the convex hulls of the base points listed in the following table, with all permutations of coordinates and sign taken. Each base point generates a distinct uniform polyteron. All coordinates correspond with uniform polytera of edge length 2.

# Base point Name CD symbol Coxeter-Dynkin
1   Pentacross o4o3o3o3x          
2   Rectified pentacross o4o3o3x3o          
3   Truncated pentacross o4o3o3x3x          
4   Birectified penteract
(Birectified pentacross)
o4o3x3o3o          
5   Cantellated pentacross o4o3x3o3x          
6   Bitruncated pentacross o4o3x3x3o          
7   cantitruncated pentacross o4o3x3x3x          
8   Rectified penteract o4x3o3o3o          
9   Runcinated pentacross o4x3o3o3x          
10   Bicantellated penteract
(Bicantellated pentacross)
o4x3o3x3o          
11   Runcitruncated pentacross o4x3o3x3x          
12   Bitruncated penteract o4x3x3o3o          
13   runcicantellated pentacross o4x3x3o3x          
14   Bicantitruncated penteract
(Bicantitruncated pentacross)
o4x3x3x3o          
15   Runcicantitruncated pentacross o4x3x3x3x          
16   Penteract x4o3o3o3o          
17   Stericated penteract
(Stericated pentacross)
x4o3o3o3x          
18   Runcinated penteract x4o3o3x3o          
19   Steritruncated pentacross x4o3o3x3x          
20   Cantellated penteract x4o3x3o3o          
21   Stericantellated penteract
(Stericantellated pentacross)
x4o3x3o3x          
22   Runcicantellated penteract x4o3x3x3o          
23   Stericantitruncated pentacross x4o3x3x3x          
24   Truncated penteract x4x3o3o3o          
25   Steritruncated penteract x4x3o3o3x          
26   Runcitruncated penteract x4x3o3x3o          
27   Steriruncitruncated penteract
(Steriruncitruncated pentacross)
x4x3o3x3x          
28   cantitruncated penteract x4x3x3o3o          
29   Stericantitruncated penteract x4x3x3o3x          
30   Runcicantitruncated penteract x4x3x3x3o          
31   Omnitruncated penteract
(omnitruncated pentacross)
x4x3x3x3x          

Simplex coordinates edit

 
The standard 2-simplex in R3
 
The permutohedron of order 3 (hexagon)

I found a useful extension - the n-simplex truncation coordinates can be found as facets of the (n+1)-orthoplexes in (n+1)-space. There's one "simplex truncation" facet in each coordinate orthant (just ignore the sign combinations) from each above polytopes with the end-node with the 4 edge unringed. Tom Ruen (talk) 02:43, 28 July 2010 (UTC)

Triangular truncations in 3-space:
# Base point Name Coxeter-Dynkin Vertices
1 (0, 0, 1) Triangle     3
2 (0, 1, 1) Rectified triangle     3
3 (0, 1, 2) Truncated triangle     6
Tetrahedra truncations in 4-space:
# Base point Name Coxeter-Dynkin Vertices
1 (0, 0, 0, 1) tetrahedron       4
2 (0, 0, 1, 1) Rectified tetrahedron       6
3 (0, 0, 1, 2) Truncated tetrahedron       12
4 (0, 1, 1, 1) Birectified tetrahedron       4
5 (0, 1, 1, 2) Cantellated tetrahedron       12
6 (0, 1, 2, 2) Bitruncated tetrahedron       12
7 (0, 1, 2, 3) Omnitruncated tetrahedron       24
Pentachora truncations in 5-space:
# Base point Name Coxeter-Dynkin Vertices
1 (0, 0, 0, 0, 1) Pentachoron         5
2 (0, 0, 0, 1, 1) Rectified pentachoron         10
3 (0, 0, 0, 1, 2) Truncated pentachoron         20
4 (0, 0, 1, 1, 1) Birectified pentachoron         10
5 (0, 0, 1, 1, 2) Cantellated pentachoron         30
6 (0, 0, 1, 2, 2) Bitruncated pentachoron         30
7 (0, 0, 1, 2, 3) Cantitruncated pentachoron         60
8 (0, 1, 1, 1, 1) Trirectified pentachoron         5
9 (0, 1, 1, 1, 2) Runcinated pentachoron         20
10 (0, 1, 1, 2, 2) Bicantellated pentachoron         30
11 (0, 1, 1, 2, 3) Runcitruncated pentachoron         60
12 (0, 1, 2, 2, 2) Tritruncated pentachoron         20
13 (0, 1, 2, 2, 3) Runcicantitruncated pentachoron         60
14 (0, 1, 2, 3, 3) Bicantitruncated pentachoron         60
15 (0, 1, 2, 3, 4) Omnitruncated pentachoron         120