Uniform 4-polytope

Summary

Schlegel diagram for the truncated 120-cell with tetrahedral cells visible
Orthographic projection of the truncated 120-cell, in the H3 Coxeter plane (D10 symmetry). Only vertices and edges are drawn.

In geometry, a uniform 4-polytope (or uniform polychoron)[1] is a 4-dimensional polytope which is vertex-transitive and whose cells are uniform polyhedra, and faces are regular polygons.

There are 47 non-prismatic convex uniform 4-polytopes. There are two infinite sets of convex prismatic forms, along with 17 cases arising as prisms of the convex uniform polyhedra. There are also an unknown number of non-convex star forms.

History of discovery

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  • Convex Regular polytopes:
    • 1852: Ludwig Schläfli proved in his manuscript Theorie der vielfachen Kontinuität that there are exactly 6 regular polytopes in 4 dimensions and only 3 in 5 or more dimensions.
  • Regular star 4-polytopes (star polyhedron cells and/or vertex figures)
    • 1852: Ludwig Schläfli also found 4 of the 10 regular star 4-polytopes, discounting 6 with cells or vertex figures {5/2,5} and {5,5/2}.
    • 1883: Edmund Hess completed the list of 10 of the nonconvex regular 4-polytopes, in his book (in German) Einleitung in die Lehre von der Kugelteilung mit besonderer Berücksichtigung ihrer Anwendung auf die Theorie der Gleichflächigen und der gleicheckigen Polyeder Einleitung in die Lehre von der Kugelteilung mit besonderer Berücksichtigung ihrer Anwendung auf die Theorie der Gleichflächigen und der gleicheckigen Polyeder, von dr. Edmund Hess. Mit sechzehn lithographierten tafeln..
  • Convex semiregular polytopes: (Various definitions before Coxeter's uniform category)
    • 1900: Thorold Gosset enumerated the list of nonprismatic semiregular convex polytopes with regular cells (Platonic solids) in his publication On the Regular and Semi-Regular Figures in Space of n Dimensions. In four dimensions, this gives the rectified 5-cell, the rectified 600-cell, and the snub 24-cell.[2]
    • 1910: Alicia Boole Stott, in her publication Geometrical deduction of semiregular from regular polytopes and space fillings, expanded the definition by also allowing Archimedean solid and prism cells. This construction enumerated 45 semiregular 4-polytopes, corresponding to the nonprismatic forms listed below. The snub 24-cell and grand antiprism were missing from her list.[3]
    • 1911: Pieter Hendrik Schoute published Analytic treatment of the polytopes regularly derived from the regular polytopes, followed Boole-Stott's notations, enumerating the convex uniform polytopes by symmetry based on 5-cell, 8-cell/16-cell, and 24-cell.
    • 1912: E. L. Elte independently expanded on Gosset's list with the publication The Semiregular Polytopes of the Hyperspaces, polytopes with one or two types of semiregular facets.[4]
  • Convex uniform polytopes:
    • 1940: The search was expanded systematically by H.S.M. Coxeter in his publication Regular and Semi-Regular Polytopes.
    • Convex uniform 4-polytopes:
      • 1965: The complete list of convex forms was finally enumerated by John Horton Conway and Michael Guy, in their publication Four-Dimensional Archimedean Polytopes, established by computer analysis, adding only one non-Wythoffian convex 4-polytope, the grand antiprism.
      • 1966 Norman Johnson completes his Ph.D. dissertation The Theory of Uniform Polytopes and Honeycombs under advisor Coxeter, completes the basic theory of uniform polytopes for dimensions 4 and higher.
      • 1986 Coxeter published a paper Regular and Semi-Regular Polytopes II which included analysis of the unique snub 24-cell structure, and the symmetry of the anomalous grand antiprism.
      • 1998[5]-2000: The 4-polytopes were systematically named by Norman Johnson, and given by George Olshevsky's online indexed enumeration (used as a basis for this listing). Johnson named the 4-polytopes as polychora, like polyhedra for 3-polytopes, from the Greek roots poly ("many") and choros ("room" or "space").[6] The names of the uniform polychora started with the 6 regular polychora with prefixes based on rings in the Coxeter diagrams; truncation t0,1, cantellation, t0,2, runcination t0,3, with single ringed forms called rectified, and bi, tri-prefixes added when the first ring was on the second or third nodes.[7][8]
      • 2004: A proof that the Conway-Guy set is complete was published by Marco Möller in his dissertation, Vierdimensionale Archimedische Polytope. Möller reproduced Johnson's naming system in his listing.[9]
      • 2008: The Symmetries of Things[10] was published by John H. Conway and contains the first print-published listing of the convex uniform 4-polytopes and higher dimensional polytopes by Coxeter group family, with general vertex figure diagrams for each ringed Coxeter diagram permutation—snub, grand antiprism, and duoprisms—which he called proprisms for product prisms. He used his own ijk-ambo naming scheme for the indexed ring permutations beyond truncation and bitruncation, and all of Johnson's names were included in the book index.
  • Nonregular uniform star 4-polytopes: (similar to the nonconvex uniform polyhedra)
    • 1966: Johnson describes three nonconvex uniform antiprisms in 4-space in his dissertation.[11]
    • 1990-2006: In a collaborative search, up to 2005 a total of 1845 uniform 4-polytopes (convex and nonconvex) had been identified by Jonathan Bowers and George Olshevsky,[12] with an additional four discovered in 2006 for a total of 1849. The count includes the 74 prisms of the 75 non-prismatic uniform polyhedra (since that is a finite set – the cubic prism is excluded as it duplicates the tesseract), but not the infinite categories of duoprisms or prisms of antiprisms.[13]
    • 2020-2023: 342 new polychora were found, bringing up the total number of known uniform 4-polytopes to 2191. The list has not been proven complete.[13][14]

Regular 4-polytopes

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Regular 4-polytopes are a subset of the uniform 4-polytopes, which satisfy additional requirements. Regular 4-polytopes can be expressed with Schläfli symbol {p,q,r} have cells of type {p,q}, faces of type {p}, edge figures {r}, and vertex figures {q,r}.

The existence of a regular 4-polytope {p,q,r} is constrained by the existence of the regular polyhedra {p,q} which becomes cells, and {q,r} which becomes the vertex figure.

Existence as a finite 4-polytope is dependent upon an inequality:[15]

The 16 regular 4-polytopes, with the property that all cells, faces, edges, and vertices are congruent:

Convex uniform 4-polytopes

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Symmetry of uniform 4-polytopes in four dimensions

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Orthogonal subgroups
The 24 mirrors of F4 can be decomposed into 2 orthogonal D4 groups:
  1. = (12 mirrors)
  2. = (12 mirrors)
The 10 mirrors of B3×A1 can be decomposed into orthogonal groups, 4A1 and D3:
  1. = (3+1 mirrors)
  2. = (6 mirrors)

There are 5 fundamental mirror symmetry point group families in 4-dimensions: A4 = , B4 = , D4 = , F4 = , H4 = .[7] There are also 3 prismatic groups A3A1 = , B3A1 = , H3A1 = , and duoprismatic groups: I2(p)×I2(q) = . Each group defined by a Goursat tetrahedron fundamental domain bounded by mirror planes.

Each reflective uniform 4-polytope can be constructed in one or more reflective point group in 4 dimensions by a Wythoff construction, represented by rings around permutations of nodes in a Coxeter diagram. Mirror hyperplanes can be grouped, as seen by colored nodes, separated by even-branches. Symmetry groups of the form [a,b,a], have an extended symmetry, [[a,b,a]], doubling the symmetry order. This includes [3,3,3], [3,4,3], and [p,2,p]. Uniform polytopes in these group with symmetric rings contain this extended symmetry.

If all mirrors of a given color are unringed (inactive) in a given uniform polytope, it will have a lower symmetry construction by removing all of the inactive mirrors. If all the nodes of a given color are ringed (active), an alternation operation can generate a new 4-polytope with chiral symmetry, shown as "empty" circled nodes", but the geometry is not generally adjustable to create uniform solutions.

Weyl
group
Conway
Quaternion
Abstract
structure
Order Coxeter
diagram
Coxeter
notation
Commutator
subgroup
Coxeter
number

(h)
Mirrors
m=2h
Irreducible
A4 +1/60[I×I].21 S5 120 [3,3,3] [3,3,3]+ 5 10
D4 ±1/3[T×T].2 1/2.2S4 192 [31,1,1] [31,1,1]+ 6 12
B4 ±1/6[O×O].2 2S4 = S2≀S4 384 [4,3,3] 8 4 12
F4 ±1/2[O×O].23 3.2S4 1152 [3,4,3] [3+,4,3+] 12 12 12
H4 ±[I×I].2 2.(A5×A5).2 14400 [5,3,3] [5,3,3]+ 30 60
Prismatic groups
A3A1 +1/24[O×O].23 S4×D1 48 [3,3,2] = [3,3]×[ ] [3,3]+ - 6 1
B3A1 ±1/24[O×O].2 S4×D1 96 [4,3,2] = [4,3]×[ ] - 3 6 1
H3A1 ±1/60[I×I].2 A5×D1 240 [5,3,2] = [5,3]×[ ] [5,3]+ - 15 1
Duoprismatic groups (Use 2p,2q for even integers)
I2(p)I2(q) ±1/2[D2p×D2q] Dp×Dq 4pq [p,2,q] = [p]×[q] [p+,2,q+] - p q
I2(2p)I2(q) ±1/2[D4p×D2q] D2p×Dq 8pq [2p,2,q] = [2p]×[q] - p p q
I2(2p)I2(2q) ±1/2[D4p×D4q] D2p×D2q 16pq [2p,2,2q] = [2p]×[2q] - p p q q

Enumeration

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There are 64 convex uniform 4-polytopes, including the 6 regular convex 4-polytopes, and excluding the infinite sets of the duoprisms and the antiprismatic prisms.

  • 5 are polyhedral prisms based on the Platonic solids (1 overlap with regular since a cubic hyperprism is a tesseract)
  • 13 are polyhedral prisms based on the Archimedean solids
  • 9 are in the self-dual regular A4 [3,3,3] group (5-cell) family.
  • 9 are in the self-dual regular F4 [3,4,3] group (24-cell) family. (Excluding snub 24-cell)
  • 15 are in the regular B4 [3,3,4] group (tesseract/16-cell) family (3 overlap with 24-cell family)
  • 15 are in the regular H4 [3,3,5] group (120-cell/600-cell) family.
  • 1 special snub form in the [3,4,3] group (24-cell) family.
  • 1 special non-Wythoffian 4-polytope, the grand antiprism.
  • TOTAL: 68 − 4 = 64

These 64 uniform 4-polytopes are indexed below by George Olshevsky. Repeated symmetry forms are indexed in brackets.

In addition to the 64 above, there are 2 infinite prismatic sets that generate all of the remaining convex forms:

The A4 family

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The 5-cell has diploid pentachoric [3,3,3] symmetry,[7] of order 120, isomorphic to the permutations of five elements, because all pairs of vertices are related in the same way.

Facets (cells) are given, grouped in their Coxeter diagram locations by removing specified nodes.

[3,3,3] uniform polytopes
# Name
Bowers name (and acronym)
Vertex
figure
Coxeter diagram
and Schläfli
symbols
Cell counts by location Element counts
Pos. 3

(5)
Pos. 2

(10)
Pos. 1

(10)
Pos. 0

(5)
Cells Faces Edges Vertices
1 5-cell
Pentachoron[7] (pen)

{3,3,3}
(4)

(3.3.3)
5 10 10 5
2 rectified 5-cell
Rectified pentachoron (rap)

r{3,3,3}
(3)

(3.3.3.3)
(2)

(3.3.3)
10 30 30 10
3 truncated 5-cell
Truncated pentachoron (tip)

t{3,3,3}
(3)

(3.6.6)
(1)

(3.3.3)
10 30 40 20
4 cantellated 5-cell
Small rhombated pentachoron (srip)

rr{3,3,3}
(2)

(3.4.3.4)
(2)

(3.4.4)
(1)

(3.3.3.3)
20 80 90 30
7 cantitruncated 5-cell
Great rhombated pentachoron (grip)

tr{3,3,3}
(2)

(4.6.6)
(1)

(3.4.4)
(1)

(3.6.6)
20 80 120 60
8 runcitruncated 5-cell
Prismatorhombated pentachoron (prip)

t0,1,3{3,3,3}
(1)

(3.6.6)
(2)

(4.4.6)
(1)

(3.4.4)
(1)

(3.4.3.4)
30 120 150 60
[[3,3,3]] uniform polytopes
# Name
Bowers name (and acronym)
Vertex
figure
Coxeter diagram

and Schläfli
symbols
Cell counts by location Element counts
Pos. 3-0

(10)
Pos. 1-2

(20)
Alt Cells Faces Edges Vertices
5 *runcinated 5-cell
Small prismatodecachoron (spid)

t0,3{3,3,3}
(2)

(3.3.3)
(6)

(3.4.4)
30 70 60 20
6 *bitruncated 5-cell
Decachoron (deca)

2t{3,3,3}
(4)

(3.6.6)
10 40 60 30
9 *omnitruncated 5-cell
Great prismatodecachoron (gippid)

t0,1,2,3{3,3,3}
(2)

(4.6.6)
(2)

(4.4.6)
30 150 240 120
Nonuniform omnisnub 5-cell
Snub decachoron (snad)
Snub pentachoron (snip)[16]

ht0,1,2,3{3,3,3}
(2)
(3.3.3.3.3)
(2)
(3.3.3.3)
(4)
(3.3.3)
90 300 270 60

The three uniform 4-polytopes forms marked with an asterisk, *, have the higher extended pentachoric symmetry, of order 240, [[3,3,3]] because the element corresponding to any element of the underlying 5-cell can be exchanged with one of those corresponding to an element of its dual. There is one small index subgroup [3,3,3]+, order 60, or its doubling [[3,3,3]]+, order 120, defining an omnisnub 5-cell which is listed for completeness, but is not uniform.

The B4 family

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This family has diploid hexadecachoric symmetry,[7] [4,3,3], of order 24×16=384: 4!=24 permutations of the four axes, 24=16 for reflection in each axis. There are 3 small index subgroups, with the first two generate uniform 4-polytopes which are also repeated in other families, [1+,4,3,3], [4,(3,3)+], and [4,3,3]+, all order 192.

Tesseract truncations

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# Name
(Bowers name and acronym)
Vertex
figure
Coxeter diagram
and Schläfli
symbols
Cell counts by location Element counts
Pos. 3

(8)
Pos. 2

(24)
Pos. 1

(32)
Pos. 0

(16)
Cells Faces Edges Vertices
10 tesseract or 8-cell
Tesseract (tes)

{4,3,3}
(4)

(4.4.4)
8 24 32 16
11 Rectified tesseract (rit)
r{4,3,3}
(3)

(3.4.3.4)
(2)

(3.3.3)
24 88 96 32
13 Truncated tesseract (tat)
t{4,3,3}
(3)

(3.8.8)
(1)

(3.3.3)
24 88 128 64
14 Cantellated tesseract
Small rhombated tesseract (srit)

rr{4,3,3}
(2)

(3.4.4.4)
(2)

(3.4.4)
(1)

(3.3.3.3)
56 248 288 96
15 Runcinated tesseract
(also runcinated 16-cell)
Small disprismatotesseractihexadecachoron (sidpith)

t0,3{4,3,3}
(1)

(4.4.4)
(3)

(4.4.4)
(3)

(3.4.4)
(1)

(3.3.3)
80 208 192 64
16 Bitruncated tesseract
(also bitruncated 16-cell)
Tesseractihexadecachoron (tah)

2t{4,3,3}
(2)

(4.6.6)
(2)

(3.6.6)
24 120 192 96
18 Cantitruncated tesseract
Great rhombated tesseract (grit)

tr{4,3,3}
(2)

(4.6.8)
(1)

(3.4.4)
(1)

(3.6.6)
56 248 384 192
19 Runcitruncated tesseract
Prismatorhombated hexadecachoron (proh)

t0,1,3{4,3,3}
(1)

(3.8.8)
(2)

(4.4.8)
(1)

(3.4.4)
(1)

(3.4.3.4)
80 368 480 192
21 Omnitruncated tesseract
(also omnitruncated 16-cell)
Great disprismatotesseractihexadecachoron (gidpith)

t0,1,2,3{3,3,4}
(1)

(4.6.8)
(1)

(4.4.8)
(1)

(4.4.6)
(1)

(4.6.6)
80 464 768 384
Related half tesseract, [1+,4,3,3] uniform 4-polytopes
# Name
(Bowers style acronym)
Vertex
figure
Coxeter diagram
and Schläfli
symbols
Cell counts by location Element counts
Pos. 3

(8)
Pos. 2

(24)
Pos. 1

(32)
Pos. 0

(16)
Alt Cells Faces Edges Vertices
12 Half tesseract
Demitesseract
= 16-cell (hex)
=
h{4,3,3}={3,3,4}
(4)

(3.3.3)
(4)

(3.3.3)
16 32 24 8
[17] Cantic tesseract
= Truncated 16-cell (thex)
=
h2{4,3,3}=t{4,3,3}
(4)

(6.6.3)
(1)

(3.3.3.3)
24 96 120 48
[11] Runcic tesseract
= Rectified tesseract (rit)
=
h3{4,3,3}=r{4,3,3}
(3)

(3.4.3.4)
(2)

(3.3.3)
24 88 96 32
[16] Runcicantic tesseract
= Bitruncated tesseract (tah)
=
h2,3{4,3,3}=2t{4,3,3}
(2)

(3.4.3.4)
(2)

(3.6.6)
24 120 192 96
[11] = Rectified tesseract (rat) =
h1{4,3,3}=r{4,3,3}
24 88 96 32
[16] = Bitruncated tesseract (tah) =
h1,2{4,3,3}=2t{4,3,3}
24 120 192 96
[23] = Rectified 24-cell (rico) =
h1,3{4,3,3}=rr{3,3,4}
48 240 288 96
[24] = Truncated 24-cell (tico) =
h1,2,3{4,3,3}=tr{3,3,4}
48 240 384 192
# Name
(Bowers style acronym)
Vertex
figure
Coxeter diagram
and Schläfli
symbols
Cell counts by location Element counts
Pos. 3

(8)
Pos. 2

(24)
Pos. 1

(32)
Pos. 0

(16)
Alt Cells Faces Edges Vertices
Nonuniform omnisnub tesseract
Snub tesseract (snet)[17]
(Or omnisnub 16-cell)

ht0,1,2,3{4,3,3}
(1)

(3.3.3.3.4)
(1)

(3.3.3.4)
(1)

(3.3.3.3)
(1)

(3.3.3.3.3)
(4)

(3.3.3)
272 944 864 192

16-cell truncations

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# Name (Bowers name and acronym) Vertex
figure
Coxeter diagram
and Schläfli
symbols
Cell counts by location Element counts
Pos. 3

(8)
Pos. 2

(24)
Pos. 1

(32)
Pos. 0

(16)
Alt Cells Faces Edges Vertices
[12] 16-cell
Hexadecachoron[7] (hex)

{3,3,4}
(8)

(3.3.3)
16 32 24 8
[22] *Rectified 16-cell
(Same as 24-cell) (ico)
=
r{3,3,4}
(2)

(3.3.3.3)
(4)

(3.3.3.3)
24 96 96 24
17 Truncated 16-cell
Truncated hexadecachoron (thex)

t{3,3,4}
(1)

(3.3.3.3)
(4)

(3.6.6)
24 96 120 48
[23] *Cantellated 16-cell
(Same as rectified 24-cell) (rico)
=
rr{3,3,4}
(1)

(3.4.3.4)
(2)

(4.4.4)
(2)

(3.4.3.4)
48 240 288 96
[15] Runcinated 16-cell
(also runcinated tesseract) (sidpith)

t0,3{3,3,4}
(1)

(4.4.4)
(3)

(4.4.4)
(3)

(3.4.4)
(1)

(3.3.3)
80 208 192 64
[16] Bitruncated 16-cell
(also bitruncated tesseract) (tah)

2t{3,3,4}
(2)

(4.6.6)
(2)

(3.6.6)
24 120 192 96
[24] *Cantitruncated 16-cell
(Same as truncated 24-cell) (tico)
=
tr{3,3,4}
(1)

(4.6.6)
(1)

(4.4.4)
(2)

(4.6.6)
48 240 384 192
20 Runcitruncated 16-cell
Prismatorhombated tesseract (prit)

t0,1,3{3,3,4}
(1)

(3.4.4.4)
(1)

(4.4.4)
(2)

(4.4.6)
(1)

(3.6.6)
80 368 480 192
[21] Omnitruncated 16-cell
(also omnitruncated tesseract) (gidpith)

t0,1,2,3{3,3,4}
(1)

(4.6.8)
(1)

(4.4.8)
(1)

(4.4.6)
(1)

(4.6.6)
80 464 768 384
[31] alternated cantitruncated 16-cell
(Same as the snub 24-cell) (sadi)

sr{3,3,4}
(1)

(3.3.3.3.3)
(1)

(3.3.3)
(2)

(3.3.3.3.3)
(4)

(3.3.3)
144 480 432 96
Nonuniform Runcic snub rectified 16-cell
Pyritosnub tesseract (pysnet)

sr3{3,3,4}
(1)

(3.4.4.4)
(2)

(3.4.4)
(1)

(4.4.4)
(1)

(3.3.3.3.3)
(2)

(3.4.4)
176 656 672 192
(*) Just as rectifying the tetrahedron produces the octahedron, rectifying the 16-cell produces the 24-cell, the regular member of the following family.

The snub 24-cell is repeat to this family for completeness. It is an alternation of the cantitruncated 16-cell or truncated 24-cell, with the half symmetry group [(3,3)+,4]. The truncated octahedral cells become icosahedra. The cubes becomes tetrahedra, and 96 new tetrahedra are created in the gaps from the removed vertices.

The F4 family

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This family has diploid icositetrachoric symmetry,[7] [3,4,3], of order 24×48=1152: the 48 symmetries of the octahedron for each of the 24 cells. There are 3 small index subgroups, with the first two isomorphic pairs generating uniform 4-polytopes which are also repeated in other families, [3+,4,3], [3,4,3+], and [3,4,3]+, all order 576.

[3,4,3] uniform 4-polytopes
# Name Vertex
figure
Coxeter diagram
and Schläfli
symbols
Cell counts by location Element counts
Pos. 3

(24)
Pos. 2

(96)
Pos. 1

(96)
Pos. 0

(24)
Cells Faces Edges Vertices
22 24-cell
(Same as rectified 16-cell)
Icositetrachoron[7] (ico)

{3,4,3}
(6)

(3.3.3.3)
24 96 96 24
23 rectified 24-cell
(Same as cantellated 16-cell)
Rectified icositetrachoron (rico)

r{3,4,3}
(3)

(3.4.3.4)
(2)

(4.4.4)
48 240 288 96
24 truncated 24-cell
(Same as cantitruncated 16-cell)
Truncated icositetrachoron (tico)

t{3,4,3}
(3)

(4.6.6)
(1)

(4.4.4)
48 240 384 192
25 cantellated 24-cell
Small rhombated icositetrachoron (srico)

rr{3,4,3}
(2)

(3.4.4.4)
(2)

(3.4.4)
(1)

(3.4.3.4)
144 720 864 288
28 cantitruncated 24-cell
Great rhombated icositetrachoron (grico)

tr{3,4,3}
(2)

(4.6.8)
(1)

(3.4.4)
(1)

(3.8.8)
144 720 1152 576
29 runcitruncated 24-cell
Prismatorhombated icositetrachoron (prico)

t0,1,3{3,4,3}
(1)

(4.6.6)
(2)

(4.4.6)
(1)

(3.4.4)
(1)

(3.4.4.4)
240 1104 1440 576
[3+,4,3] uniform 4-polytopes
# Name Vertex
figure
Coxeter diagram
and Schläfli
symbols
Cell counts by location Element counts
Pos. 3

(24)
Pos. 2

(96)
Pos. 1

(96)
Pos. 0

(24)
Alt Cells Faces Edges Vertices
31 snub 24-cell
Snub disicositetrachoron (sadi)

s{3,4,3}
(3)

(3.3.3.3.3)
(1)

(3.3.3)
(4)

(3.3.3)
144 480 432 96
Nonuniform runcic snub 24-cell
Prismatorhombisnub icositetrachoron (prissi)

s3{3,4,3}
(1)

(3.3.3.3.3)
(2)

(3.4.4)
(1)

(3.6.6)
(3)

Tricup
240 960 1008 288
[25] cantic snub 24-cell
(Same as cantellated 24-cell) (srico)

s2{3,4,3}
(2)

(3.4.4.4)
(1)

(3.4.3.4)
(2)

(3.4.4)
144 720 864 288
[29] runcicantic snub 24-cell
(Same as runcitruncated 24-cell) (prico)

s2,3{3,4,3}
(1)

(4.6.6)
(1)

(3.4.4)
(1)

(3.4.4.4)
(2)

(4.4.6)
240 1104 1440 576
(†) The snub 24-cell here, despite its common name, is not analogous to the snub cube; rather, it is derived by an alternation of the truncated 24-cell. Its symmetry number is only 576, (the ionic diminished icositetrachoric group, [3+,4,3]).

Like the 5-cell, the 24-cell is self-dual, and so the following three forms have twice as many symmetries, bringing their total to 2304 (extended icositetrachoric symmetry [[3,4,3]]).

[[3,4,3]] uniform 4-polytopes
# Name Vertex
figure
Coxeter diagram

and Schläfli
symbols
Cell counts by location Element counts
Pos. 3-0


(48)
Pos. 2-1


(192)
Cells Faces Edges Vertices
26 runcinated 24-cell
Small prismatotetracontoctachoron (spic)

t0,3{3,4,3}
(2)

(3.3.3.3)
(6)

(3.4.4)
240 672 576 144
27 bitruncated 24-cell
Tetracontoctachoron (cont)

2t{3,4,3}
(4)

(3.8.8)
48 336 576 288
30 omnitruncated 24-cell
Great prismatotetracontoctachoron (gippic)

t0,1,2,3{3,4,3}
(2)

(4.6.8)
(2)

(4.4.6)
240 1392 2304 1152
[[3,4,3]]+ isogonal 4-polytope
# Name Vertex
figure
Coxeter diagram
and Schläfli
symbols
Cell counts by location Element counts
Pos. 3-0


(48)
Pos. 2-1


(192)
Alt Cells Faces Edges Vertices
Nonuniform omnisnub 24-cell
Snub tetracontoctachoron (snoc)
Snub icositetrachoron (sni)[18]

ht0,1,2,3{3,4,3}
(2)

(3.3.3.3.4)
(2)

(3.3.3.3)
(4)

(3.3.3)
816 2832 2592 576

The H4 family

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This family has diploid hexacosichoric symmetry,[7] [5,3,3], of order 120×120=24×600=14400: 120 for each of the 120 dodecahedra, or 24 for each of the 600 tetrahedra. There is one small index subgroups [5,3,3]+, all order 7200.

120-cell truncations

edit
# Name
(Bowers name and acronym)
Vertex
figure
Coxeter diagram
and Schläfli
symbols
Cell counts by location Element counts
Pos. 3

(120)
Pos. 2

(720)
Pos. 1

(1200)
Pos. 0

(600)
Alt Cells Faces Edges Vertices
32 120-cell
(hecatonicosachoron or dodecacontachoron)[7]
Hecatonicosachoron (hi)

{5,3,3}
(4)

(5.5.5)
120 720 1200 600
33 rectified 120-cell
Rectified hecatonicosachoron (rahi)

r{5,3,3}
(3)

(3.5.3.5)
(2)

(3.3.3)
720 3120 3600 1200
36 truncated 120-cell
Truncated hecatonicosachoron (thi)

t{5,3,3}
(3)

(3.10.10)
(1)

(3.3.3)
720 3120 4800 2400
37 cantellated 120-cell
Small rhombated hecatonicosachoron (srahi)

rr{5,3,3}
(2)

(3.4.5.4)
(2)

(3.4.4)
(1)

(3.3.3.3)
1920 9120 10800 3600
38 runcinated 120-cell
(also runcinated 600-cell)
Small disprismatohexacosihecatonicosachoron (sidpixhi)

t0,3{5,3,3}
(1)

(5.5.5)
(3)

(4.4.5)
(3)

(3.4.4)
(1)

(3.3.3)
2640 7440 7200 2400
39 bitruncated 120-cell
(also bitruncated 600-cell)
Hexacosihecatonicosachoron (xhi)

2t{5,3,3}
(2)

(5.6.6)
(2)

(3.6.6)
720 4320 7200 3600
42 cantitruncated 120-cell
Great rhombated hecatonicosachoron (grahi)

tr{5,3,3}
(2)

(4.6.10)
(1)

(3.4.4)
(1)

(3.6.6)
1920 9120 14400 7200
43 runcitruncated 120-cell
Prismatorhombated hexacosichoron (prix)

t0,1,3{5,3,3}
(1)

(3.10.10)
(2)

(4.4.10)
(1)

(3.4.4)
(1)

(3.4.3.4)
2640 13440 18000 7200
46 omnitruncated 120-cell
(also omnitruncated 600-cell)
Great disprismatohexacosihecatonicosachoron (gidpixhi)

t0,1,2,3{5,3,3}
(1)

(4.6.10)
(1)

(4.4.10)
(1)

(4.4.6)
(1)

(4.6.6)
2640 17040 28800 14400
Nonuniform omnisnub 120-cell
Snub hecatonicosachoron (snixhi)[19]
(Same as the omnisnub 600-cell)

ht0,1,2,3{5,3,3}
(1)
(3.3.3.3.5)
(1)
(3.3.3.5)
(1)
(3.3.3.3)
(1)
(3.3.3.3.3)
(4)
(3.3.3)
9840 35040 32400 7200

600-cell truncations

edit
# Name
(Bowers style acronym)
Vertex
figure
Coxeter diagram
and Schläfli
symbols
Symmetry Cell counts by location Element counts
Pos. 3

(120)
Pos. 2

(720)
Pos. 1

(1200)
Pos. 0

(600)
Cells Faces Edges Vertices
35 600-cell
Hexacosichoron[7] (ex)

{3,3,5}
[5,3,3]
order 14400
(20)

(3.3.3)
600 1200 720 120
[47] 20-diminished 600-cell
= Grand antiprism (gap)
Nonwythoffian
construction
[[10,2+,10]]
order 400
Index 36
(2)

(3.3.3.5)
(12)

(3.3.3)
320 720 500 100
[31] 24-diminished 600-cell
= Snub 24-cell (sadi)
Nonwythoffian
construction
[3+,4,3]
order 576
index 25
(3)

(3.3.3.3.3)
(5)

(3.3.3)
144 480 432 96
Nonuniform bi-24-diminished 600-cell
Bi-icositetradiminished hexacosichoron (bidex)
Nonwythoffian
construction
order 144
index 100
(6)

tdi
48 192 216 72
34 rectified 600-cell
Rectified hexacosichoron (rox)

r{3,3,5}
[5,3,3] (2)

(3.3.3.3.3)
(5)

(3.3.3.3)
720 3600 3600 720
Nonuniform 120-diminished rectified 600-cell
Swirlprismatodiminished rectified hexacosichoron (spidrox)
Nonwythoffian
construction
order 1200
index 12
(2)

3.3.3.5
(2)

4.4.5
(5)

P4
840 2640 2400 600
41 truncated 600-cell
Truncated hexacosichoron (tex)

t{3,3,5}
[5,3,3] (1)

(3.3.3.3.3)
(5)

(3.6.6)
720 3600 4320 1440
40 cantellated 600-cell
Small rhombated hexacosichoron (srix)

rr{3,3,5}
[5,3,3] (1)

(3.5.3.5)
(2)

(4.4.5)
(1)

(3.4.3.4)
1440 8640 10800 3600
[38] runcinated 600-cell
(also runcinated 120-cell) (sidpixhi)

t0,3{3,3,5}
[5,3,3] (1)

(5.5.5)
(3)

(4.4.5)
(3)

(3.4.4)
(1)

(3.3.3)
2640 7440 7200 2400
[39] bitruncated 600-cell
(also bitruncated 120-cell) (xhi)

2t{3,3,5}
[5,3,3] (2)

(5.6.6)
(2)

(3.6.6)
720 4320 7200 3600
45 cantitruncated 600-cell
Great rhombated hexacosichoron (grix)

tr{3,3,5}
[5,3,3] (1)

(5.6.6)
(1)

(4.4.5)
(2)

(4.6.6)
1440 8640 14400 7200
44 runcitruncated 600-cell
Prismatorhombated hecatonicosachoron (prahi)

t0,1,3{3,3,5}
[5,3,3] (1)

(3.4.5.4)
(1)

(4.4.5)
(2)

(4.4.6)
(1)

(3.6.6)
2640 13440 18000 7200
[46] omnitruncated 600-cell
(also omnitruncated 120-cell) (gidpixhi)

t0,1,2,3{3,3,5}
[5,3,3] (1)

(4.6.10)
(1)

(4.4.10)
(1)

(4.4.6)
(1)

(4.6.6)
2640 17040 28800 14400

The D4 family

edit

This demitesseract family, [31,1,1], introduces no new uniform 4-polytopes, but it is worthy to repeat these alternative constructions. This family has order 12×16=192: 4!/2=12 permutations of the four axes, half as alternated, 24=16 for reflection in each axis. There is one small index subgroups that generating uniform 4-polytopes, [31,1,1]+, order 96.

[31,1,1] uniform 4-polytopes
# Name (Bowers style acronym) Vertex
figure
Coxeter diagram

=
=
Cell counts by location Element counts
Pos. 0

(8)
Pos. 2

(24)
Pos. 1

(8)
Pos. 3

(8)
Pos. Alt
(96)
3 2 1 0
[12] demitesseract
half tesseract
(Same as 16-cell) (hex)
=
h{4,3,3}
(4)

(3.3.3)
(4)

(3.3.3)
16 32 24 8
[17] cantic tesseract
(Same as truncated 16-cell) (thex)
=
h2{4,3,3}
(1)

(3.3.3.3)
(2)

(3.6.6)
(2)

(3.6.6)
24 96 120 48
[11] runcic tesseract
(Same as rectified tesseract) (rit)
=
h3{4,3,3}
(1)

(3.3.3)
(1)

(3.3.3)
(3)

(3.4.3.4)
24 88 96 32
[16] runcicantic tesseract
(Same as bitruncated tesseract) (tah)
=
h2,3{4,3,3}
(1)

(3.6.6)
(1)

(3.6.6)
(2)

(4.6.6)
24 96 96 24

When the 3 bifurcated branch nodes are identically ringed, the symmetry can be increased by 6, as [3[31,1,1]] = [3,4,3], and thus these polytopes are repeated from the 24-cell family.

[3[31,1,1]] uniform 4-polytopes
# Name (Bowers style acronym) Vertex
figure
Coxeter diagram
=
=
Cell counts by location Element counts
Pos. 0,1,3

(24)
Pos. 2

(24)
Pos. Alt
(96)
3 2 1 0
[22] rectified 16-cell
(Same as 24-cell) (ico)
= = =
{31,1,1} = r{3,3,4} = {3,4,3}
(6)

(3.3.3.3)
48 240 288 96
[23] cantellated 16-cell
(Same as rectified 24-cell) (rico)
= = =
r{31,1,1} = rr{3,3,4} = r{3,4,3}
(3)

(3.4.3.4)
(2)

(4.4.4)
24 120 192 96
[24] cantitruncated 16-cell
(Same as truncated 24-cell) (tico)
= = =
t{31,1,1} = tr{3,3,4} = t{3,4,3}
(3)

(4.6.6)
(1)

(4.4.4)
48 240 384 192
[31] snub 24-cell (sadi) = = =
s{31,1,1} = sr{3,3,4} = s{3,4,3}
(3)

(3.3.3.3.3)
(1)

(3.3.3)
(4)

(3.3.3)
144 480 432 96

Here again the snub 24-cell, with the symmetry group [31,1,1]+ this time, represents an alternated truncation of the truncated 24-cell creating 96 new tetrahedra at the position of the deleted vertices. In contrast to its appearance within former groups as partly snubbed 4-polytope, only within this symmetry group it has the full analogy to the Kepler snubs, i.e. the snub cube and the snub dodecahedron.

The grand antiprism

edit

There is one non-Wythoffian uniform convex 4-polytope, known as the grand antiprism, consisting of 20 pentagonal antiprisms forming two perpendicular rings joined by 300 tetrahedra. It is loosely analogous to the three-dimensional antiprisms, which consist of two parallel polygons joined by a band of triangles. Unlike them, however, the grand antiprism is not a member of an infinite family of uniform polytopes.

Its symmetry is the ionic diminished Coxeter group, [[10,2+,10]], order 400.

# Name (Bowers style acronym) Picture Vertex
figure
Coxeter diagram
and Schläfli
symbols
Cells by type Element counts Net
Cells Faces Edges Vertices
47 grand antiprism (gap) No symbol 300
(3.3.3)
20
(3.3.3.5)
320 20 {5}
700 {3}
500 100

Prismatic uniform 4-polytopes

edit

A prismatic polytope is a Cartesian product of two polytopes of lower dimension; familiar examples are the 3-dimensional prisms, which are products of a polygon and a line segment. The prismatic uniform 4-polytopes consist of two infinite families:

  • Polyhedral prisms: products of a line segment and a uniform polyhedron. This family is infinite because it includes prisms built on 3-dimensional prisms and antiprisms.
  • Duoprisms: products of two polygons.

Convex polyhedral prisms

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The most obvious family of prismatic 4-polytopes is the polyhedral prisms, i.e. products of a polyhedron with a line segment. The cells of such a 4-polytopes are two identical uniform polyhedra lying in parallel hyperplanes (the base cells) and a layer of prisms joining them (the lateral cells). This family includes prisms for the 75 nonprismatic uniform polyhedra (of which 18 are convex; one of these, the cube-prism, is listed above as the tesseract).[citation needed]

There are 18 convex polyhedral prisms created from 5 Platonic solids and 13 Archimedean solids as well as for the infinite families of three-dimensional prisms and antiprisms.[citation needed] The symmetry number of a polyhedral prism is twice that of the base polyhedron.

Tetrahedral prisms: A3 × A1

edit

This prismatic tetrahedral symmetry is [3,3,2], order 48. There are two index 2 subgroups, [(3,3)+,2] and [3,3,2]+, but the second doesn't generate a uniform 4-polytope.

[3,3,2] uniform 4-polytopes
# Name (Bowers style acronym) Picture Vertex
figure
Coxeter diagram
and Schläfli
symbols
Cells by type Element counts Net
Cells Faces Edges Vertices
48 Tetrahedral prism (tepe)
{3,3}×{ }
t0,3{3,3,2}
2
3.3.3
4
3.4.4
6 8 {3}
6 {4}
16 8
49 Truncated tetrahedral prism (tuttip)
t{3,3}×{ }
t0,1,3{3,3,2}
2
3.6.6
4
3.4.4
4
4.4.6
10 8 {3}
18 {4}
8 {6}
48 24
[[3,3],2] uniform 4-polytopes
# Name (Bowers style acronym) Picture Vertex
figure
Coxeter diagram
and Schläfli
symbols
Cells by type Element counts Net
Cells Faces Edges Vertices
[51] Rectified tetrahedral prism
(Same as octahedral prism) (ope)

r{3,3}×{ }
t1,3{3,3,2}
2
3.3.3.3
4
3.4.4
6 16 {3}
12 {4}
30 12
[50] Cantellated tetrahedral prism
(Same as cuboctahedral prism) (cope)

rr{3,3}×{ }
t0,2,3{3,3,2}
2
3.4.3.4
8
3.4.4
6
4.4.4
16 16 {3}
36 {4}
60 24
[54] Cantitruncated tetrahedral prism
(Same as truncated octahedral prism) (tope)

tr{3,3}×{ }
t0,1,2,3{3,3,2}
2
4.6.6
8
6.4.4
6
4.4.4
16 48 {4}
16 {6}
96 48
[59] Snub tetrahedral prism
(Same as icosahedral prism) (ipe)

sr{3,3}×{ }
2
3.3.3.3.3
20
3.4.4
22 40 {3}
30 {4}
72 24
Nonuniform omnisnub tetrahedral antiprism
Pyritohedral icosahedral antiprism (pikap)

2
3.3.3.3.3
8
3.3.3.3
6+24
3.3.3
40 16+96 {3} 96 24

Octahedral prisms: B3 × A1

edit

This prismatic octahedral family symmetry is [4,3,2], order 96. There are 6 subgroups of index 2, order 48 that are expressed in alternated 4-polytopes below. Symmetries are [(4,3)+,2], [1+,4,3,2], [4,3,2+], [4,3+,2], [4,(3,2)+], and [4,3,2]+.

# Name (Bowers style acronym) Picture Vertex
figure
Coxeter diagram
and Schläfli
symbols
Cells by type Element counts Net
Cells Faces Edges Vertices
[10] Cubic prism
(Same as tesseract)
(Same as 4-4 duoprism) (tes)

{4,3}×{ }
t0,3{4,3,2}
2
4.4.4
6
4.4.4
8 24 {4} 32 16
50 Cuboctahedral prism
(Same as cantellated tetrahedral prism) (cope)

r{4,3}×{ }
t1,3{4,3,2}
2
3.4.3.4
8
3.4.4
6
4.4.4
16 16 {3}
36 {4}
60 24
51 Octahedral prism
(Same as rectified tetrahedral prism)
(Same as triangular antiprismatic prism) (ope)

{3,4}×{ }
t2,3{4,3,2}
2
3.3.3.3
8
3.4.4
10 16 {3}
12 {4}
30 12
52 Rhombicuboctahedral prism (sircope)
rr{4,3}×{ }
t0,2,3{4,3,2}
2
3.4.4.4
8
3.4.4
18
4.4.4
28 16 {3}
84 {4}
120 48
53 Truncated cubic prism (ticcup)
t{4,3}×{ }
t0,1,3{4,3,2}
2
3.8.8
8
3.4.4
6
4.4.8
16 16 {3}
36 {4}
12 {8}
96 48
54 Truncated octahedral prism
(Same as cantitruncated tetrahedral prism) (tope)

t{3,4}×{ }
t1,2,3{4,3,2}
2
4.6.6
6
4.4.4
8
4.4.6
16 48 {4}
16 {6}
96 48
55 Truncated cuboctahedral prism (gircope)
tr{4,3}×{ }
t0,1,2,3{4,3,2}
2
4.6.8
12
4.4.4
8
4.4.6
6
4.4.8
28 96 {4}
16 {6}
12 {8}
192 96
56 Snub cubic prism (sniccup)
sr{4,3}×{ }
2
3.3.3.3.4
32
3.4.4
6
4.4.4
40 64 {3}
72 {4}
144 48
[48] Tetrahedral prism (tepe)
h{4,3}×{ }
2
3.3.3
4
3.4.4
6 8 {3}
6 {4}
16 8
[49] Truncated tetrahedral prism (tuttip)
h2{4,3}×{ }
2
3.3.6
4
3.4.4
4
4.4.6
6 8 {3}
6 {4}
16 8
[50] Cuboctahedral prism (cope)
rr{3,3}×{ }
2
3.4.3.4
8
3.4.4
6
4.4.4
16 16 {3}
36 {4}
60 24
[52] Rhombicuboctahedral prism (sircope)
s2{3,4}×{ }
2
3.4.4.4
8
3.4.4
18
4.4.4
28 16 {3}
84 {4}
120 48
[54] Truncated octahedral prism (tope)
tr{3,3}×{ }
2
4.6.6
6
4.4.4
8
4.4.6
16 48 {4}
16 {6}
96 48
[59] Icosahedral prism (ipe)
s{3,4}×{ }
2
3.3.3.3.3
20
3.4.4
22 40 {3}
30 {4}
72 24
[12] 16-cell (hex)
s{2,4,3}
2+6+8
3.3.3.3
16 32 {3} 24 8
Nonuniform Omnisnub tetrahedral antiprism
= Pyritohedral icosahedral antiprism (pikap)

sr{2,3,4}
2
3.3.3.3.3
8
3.3.3.3
6+24
3.3.3
40 16+96 {3} 96 24
Nonuniform Edge-snub octahedral hosochoron
Pyritosnub alterprism (pysna)

sr3{2,3,4}
2
3.4.4.4
6
4.4.4
8
3.3.3.3
24
3.4.4
40 16+48 {3}
12+12+24+24 {4}
144 48
Nonuniform Omnisnub cubic antiprism
Snub cubic antiprism (sniccap)

2
3.3.3.3.4
12+48
3.3.3
8
3.3.3.3
6
3.3.3.4
76 16+192 {3}
12 {4}
192 48
Nonuniform Runcic snub cubic hosochoron
Truncated tetrahedral alterprism (tuta)

s3{2,4,3}
2
3.6.6
6
3.3.3
8
triangular cupola
16 52 60 24

Icosahedral prisms: H3 × A1

edit

This prismatic icosahedral symmetry is [5,3,2], order 240. There are two index 2 subgroups, [(5,3)+,2] and [5,3,2]+, but the second doesn't generate a uniform polychoron.

# Name (Bowers name and acronym) Picture Vertex
figure
Coxeter diagram
and Schläfli
symbols
Cells by type Element counts Net
Cells Faces Edges Vertices
57 Dodecahedral prism (dope)
{5,3}×{ }
t0,3{5,3,2}
2
5.5.5
12
4.4.5
14 30 {4}
24 {5}
80 40
58 Icosidodecahedral prism (iddip)
r{5,3}×{ }
t1,3{5,3,2}
2
3.5.3.5
20
3.4.4
12
4.4.5
34 40 {3}
60 {4}
24 {5}
150 60
59 Icosahedral prism
(same as snub tetrahedral prism) (ipe)

{3,5}×{ }
t2,3{5,3,2}
2
3.3.3.3.3
20
3.4.4
22 40 {3}
30 {4}
72 24
60 Truncated dodecahedral prism (tiddip)
t{5,3}×{ }
t0,1,3{5,3,2}
2
3.10.10
20
3.4.4
12
4.4.10
34 40 {3}
90 {4}
24 {10}
240 120
61 Rhombicosidodecahedral prism (sriddip)
rr{5,3}×{ }
t0,2,3{5,3,2}
2
3.4.5.4
20
3.4.4
30
4.4.4
12
4.4.5
64 40 {3}
180 {4}
24 {5}
300 120
62 Truncated icosahedral prism (tipe)
t{3,5}×{ }
t1,2,3{5,3,2}
2
5.6.6
12
4.4.5
20
4.4.6
34 90 {4}
24 {5}
40 {6}
240 120
63 Truncated icosidodecahedral prism (griddip)
tr{5,3}×{ }
t0,1,2,3{5,3,2}
2
4.6.10
30
4.4.4
20
4.4.6
12
4.4.10
64 240 {4}
40 {6}
24 {10}
480 240
64 Snub dodecahedral prism (sniddip)
sr{5,3}×{ }
2
3.3.3.3.5
80
3.4.4
12
4.4.5
94 160 {3}
150 {4}
24 {5}
360 120
Nonuniform Omnisnub dodecahedral antiprism
Snub dodecahedral antiprism (sniddap)

2
3.3.3.3.5
30+120
3.3.3
20
3.3.3.3
12
3.3.3.5
184 20+240 {3}
24 {5}
220 120

Duoprisms: [p] × [q]

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The simplest of the duoprisms, the 3,3-duoprism, in Schlegel diagram, one of 6 triangular prism cells shown.

The second is the infinite family of uniform duoprisms, products of two regular polygons. A duoprism's Coxeter-Dynkin diagram is . Its vertex figure is a disphenoid tetrahedron, .

This family overlaps with the first: when one of the two "factor" polygons is a square, the product is equivalent to a hyperprism whose base is a three-dimensional prism. The symmetry number of a duoprism whose factors are a p-gon and a q-gon (a "p,q-duoprism") is 4pq if pq; if the factors are both p-gons, the symmetry number is 8p2. The tesseract can also be considered a 4,4-duoprism.

The extended f-vector of {p}×{q} is (p,p,1)*(q,q,1) = (pq,2pq,pq+p+q,p+q).

  • Cells: p q-gonal prisms, q p-gonal prisms
  • Faces: pq squares, p q-gons, q p-gons
  • Edges: 2pq
  • Vertices: pq

There is no uniform analogue in four dimensions to the infinite family of three-dimensional antiprisms.

Infinite set of p-q duoprism - - p q-gonal prisms, q p-gonal prisms:

Name Coxeter graph Cells Images Net
3-3 duoprism (triddip) 3+3 triangular prisms
3-4 duoprism (tisdip) 3 cubes
4 triangular prisms
4-4 duoprism (tes)
(same as tesseract)
4+4 cubes
3-5 duoprism (trapedip) 3 pentagonal prisms
5 triangular prisms
4-5 duoprism (squipdip) 4 pentagonal prisms
5 cubes
5-5 duoprism (pedip) 5+5 pentagonal prisms
3-6 duoprism (thiddip) 3 hexagonal prisms
6 triangular prisms
4-6 duoprism (shiddip) 4 hexagonal prisms
6 cubes
5-6 duoprism (phiddip) 5 hexagonal prisms
6 pentagonal prisms
6-6 duoprism (hiddip) 6+6 hexagonal prisms

3-3

3-4

3-5

3-6

3-7

3-8

4-3

4-4

4-5

4-6

4-7

4-8

5-3

5-4

5-5

5-6

5-7

5-8

6-3

6-4

6-5

6-6

6-7

6-8

7-3

7-4

7-5

7-6

7-7

7-8

8-3

8-4

8-5

8-6

8-7

8-8

Alternations are possible. = gives the family of duoantiprisms, but they generally cannot be made uniform. p=q=2 is the only convex case that can be made uniform, giving the regular 16-cell. p=5, q=5/3 is the only nonconvex case that can be made uniform, giving the so-called great duoantiprism. gives the p-2q-gonal prismantiprismoid (an edge-alternation of the 2p-4q duoprism), but this cannot be made uniform in any cases.[20]

Polygonal prismatic prisms: [p] × [ ] × [ ]

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The infinite set of uniform prismatic prisms overlaps with the 4-p duoprisms: (p≥3) - - p cubes and 4 p-gonal prisms - (All are the same as 4-p duoprism) The second polytope in the series is a lower symmetry of the regular tesseract, {4}×{4}.


Convex p-gonal prismatic prisms
Name {3}×{4} {4}×{4} {5}×{4} {6}×{4} {7}×{4} {8}×{4} {p}×{4}
Coxeter
diagrams



Image




Cells 3 {4}×{}
4 {3}×{}
4 {4}×{}
4 {4}×{}
5 {4}×{}
4 {5}×{}
6 {4}×{}
4 {6}×{}
7 {4}×{}
4 {7}×{}
8 {4}×{}
4 {8}×{}
p {4}×{}
4 {p}×{}
Net


Polygonal antiprismatic prisms: [p] × [ ] × [ ]

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The infinite sets of uniform antiprismatic prisms are constructed from two parallel uniform antiprisms): (p≥2) - - 2 p-gonal antiprisms, connected by 2 p-gonal prisms and 2p triangular prisms.

Convex p-gonal antiprismatic prisms
Name s{2,2}×{} s{2,3}×{} s{2,4}×{} s{2,5}×{} s{2,6}×{} s{2,7}×{} s{2,8}×{} s{2,p}×{}
Coxeter
diagram








Image
Vertex
figure
Cells 2 s{2,2}
(2) {2}×{}={4}
4 {3}×{}
2 s{2,3}
2 {3}×{}
6 {3}×{}
2 s{2,4}
2 {4}×{}
8 {3}×{}
2 s{2,5}
2 {5}×{}
10 {3}×{}
2 s{2,6}
2 {6}×{}
12 {3}×{}
2 s{2,7}
2 {7}×{}
14 {3}×{}
2 s{2,8}
2 {8}×{}
16 {3}×{}
2 s{2,p}
2 {p}×{}
2p {3}×{}
Net

A p-gonal antiprismatic prism has 4p triangle, 4p square and 4 p-gon faces. It has 10p edges, and 4p vertices.

Nonuniform alternations

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Like the 3-dimensional snub cube, , an alternation removes half the vertices, in two chiral sets of vertices from the ringed form , however the uniform solution requires the vertex positions be adjusted for equal lengths. In four dimensions, this adjustment is only possible for 2 alternated figures, while the rest only exist as nonequilateral alternated figures.

Coxeter showed only two uniform solutions for rank 4 Coxeter groups with all rings alternated (shown with empty circle nodes). The first is , s{21,1,1} which represented an index 24 subgroup (symmetry [2,2,2]+, order 8) form of the demitesseract, , h{4,3,3} (symmetry [1+,4,3,3] = [31,1,1], order 192). The second is , s{31,1,1}, which is an index 6 subgroup (symmetry [31,1,1]+, order 96) form of the snub 24-cell, , s{3,4,3}, (symmetry [3+,4,3], order 576).

Other alternations, such as , as an alternation from the omnitruncated tesseract , can not be made uniform as solving for equal edge lengths are in general overdetermined (there are six equations but only four variables). Such nonuniform alternated figures can be constructed as vertex-transitive 4-polytopes by the removal of one of two half sets of the vertices of the full ringed figure, but will have unequal edge lengths. Just like uniform alternations, they will have half of the symmetry of uniform figure, like [4,3,3]+, order 192, is the symmetry of the alternated omnitruncated tesseract.[21]

Wythoff constructions with alternations produce vertex-transitive figures that can be made equilateral, but not uniform because the alternated gaps (around the removed vertices) create cells that are not regular or semiregular. A proposed name for such figures is scaliform polytopes.[22] This category allows a subset of Johnson solids as cells, for example triangular cupola.

Each vertex configuration within a Johnson solid must exist within the vertex figure. For example, a square pyramid has two vertex configurations: 3.3.4 around the base, and 3.3.3.3 at the apex.

The nets and vertex figures of the four convex equilateral cases are given below, along with a list of cells around each vertex.

Four convex vertex-transitive equilateral 4-polytopes with nonuniform cells
Coxeter
diagram
s3{2,4,3}, s3{3,4,3}, Others
Relation 24 of 48 vertices of
rhombicuboctahedral prism
288 of 576 vertices of
runcitruncated 24-cell
72 of 120 vertices
of 600-cell
600 of 720 vertices
of rectified 600-cell
Projection
Two rings of pyramids
Net
runcic snub cubic hosochoron[23][24]

runcic snub 24-cell[25][26]
[27][28][29] [30][31]
Cells
Vertex
figure

(1) 3.4.3.4: triangular cupola
(2) 3.4.6: triangular cupola
(1) 3.3.3: tetrahedron
(1) 3.6.6: truncated tetrahedron

(1) 3.4.3.4: triangular cupola
(2) 3.4.6: triangular cupola
(2) 3.4.4: triangular prism
(1) 3.6.6: truncated tetrahedron
(1) 3.3.3.3.3: icosahedron

(2) 3.3.3.5: tridiminished icosahedron
(4) 3.5.5: tridiminished icosahedron

(1) 3.3.3.3: square pyramid
(4) 3.3.4: square pyramid
(2) 4.4.5: pentagonal prism
(2) 3.3.3.5 pentagonal antiprism

Geometric derivations for 46 nonprismatic Wythoffian uniform polychora

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The 46 Wythoffian 4-polytopes include the six convex regular 4-polytopes. The other forty can be derived from the regular polychora by geometric operations which preserve most or all of their symmetries, and therefore may be classified by the symmetry groups that they have in common.


Summary chart of truncation operations

Example locations of kaleidoscopic generator point on fundamental domain.

The geometric operations that derive the 40 uniform 4-polytopes from the regular 4-polytopes are truncating operations. A 4-polytope may be truncated at the vertices, edges or faces, leading to addition of cells corresponding to those elements, as shown in the columns of the tables below.

The Coxeter-Dynkin diagram shows the four mirrors of the Wythoffian kaleidoscope as nodes, and the edges between the nodes are labeled by an integer showing the angle between the mirrors (π/n radians or 180/n degrees). Circled nodes show which mirrors are active for each form; a mirror is active with respect to a vertex that does not lie on it.

Operation Schläfli symbol Symmetry Coxeter diagram Description
Parent t0{p,q,r} [p,q,r] Original regular form {p,q,r}
Rectification t1{p,q,r} Truncation operation applied until the original edges are degenerated into points.
Birectification
(Rectified dual)
t2{p,q,r} Face are fully truncated to points. Same as rectified dual.
Trirectification
(dual)
t3{p,q,r} Cells are truncated to points. Regular dual {r,q,p}
Truncation t0,1{p,q,r} Each vertex is cut off so that the middle of each original edge remains. Where the vertex was, there appears a new cell, the parent's vertex figure. Each original cell is likewise truncated.
Bitruncation t1,2{p,q,r} A truncation between a rectified form and the dual rectified form.
Tritruncation t2,3{p,q,r} Truncated dual {r,q,p}.
Cantellation t0,2{p,q,r} A truncation applied to edges and vertices and defines a progression between the regular and dual rectified form.
Bicantellation t1,3{p,q,r} Cantellated dual {r,q,p}.
Runcination
(or expansion)
t0,3{p,q,r} A truncation applied to the cells, faces and edges; defines a progression between a regular form and the dual.
Cantitruncation t0,1,2{p,q,r}