Uniform tilings in hyperbolic plane

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Examples of uniform tilings
Spherical Euclidean Hyperbolic
Uniform tiling 532-t0.png
{5,3}
5.5.5
CDel node 1.pngCDel 5.pngCDel node.pngCDel 3.pngCDel node.png
Uniform tiling 63-t0.png
{6,3}
6.6.6
CDel node 1.pngCDel 6.pngCDel node.pngCDel 3.pngCDel node.png
Uniform tiling 73-t0.png
{7,3}
7.7.7
CDel node 1.pngCDel 7.pngCDel node.pngCDel 3.pngCDel node.png
H2 tiling 23i-1.png
{∞,3}
∞.∞.∞
CDel node 1.pngCDel infin.pngCDel node.pngCDel 3.pngCDel node.png
Regular tilings of the sphere {p,q}, Euclidean plane, and hyperbolic plane using regular pentagonal, hexagonal and heptagonal and apeirogonal faces.
Uniform tiling 532-t01.png
t{5,3}
10.10.3
CDel node 1.pngCDel 5.pngCDel node 1.pngCDel 3.pngCDel node.png
Uniform tiling 63-t01.png
t{6,3}
12.12.3
CDel node 1.pngCDel 6.pngCDel node 1.pngCDel 3.pngCDel node.png
Uniform tiling 73-t01.png
t{7,3}
14.14.3
CDel node 1.pngCDel 7.pngCDel node 1.pngCDel 3.pngCDel node.png
H2 tiling 23i-3.png
t{∞,3}
∞.∞.3
CDel node 1.pngCDel infin.pngCDel node 1.pngCDel 3.pngCDel node.png
Truncated tilings have 2p.2p.q vertex figures from regular {p,q}
Uniform tiling 532-t1.png
r{5,3}
3.5.3.5
CDel node.pngCDel 5.pngCDel node 1.pngCDel 3.pngCDel node.png
Uniform tiling 63-t1.png
r{6,3}
3.6.3.6
CDel node.pngCDel 6.pngCDel node 1.pngCDel 3.pngCDel node.png
Uniform tiling 73-t1.png
r{7,3}
3.7.3.7
CDel node.pngCDel 7.pngCDel node 1.pngCDel 3.pngCDel node.png
H2 tiling 23i-2.png
r{∞,3}
3.∞.3.∞
CDel node.pngCDel infin.pngCDel node 1.pngCDel 3.pngCDel node.png
Quasiregular tilings are similar to regular tilings but alternate two types of regular polygon around each vertex.
Uniform tiling 532-t02.png
rr{5,3}
3.4.5.4
CDel node 1.pngCDel 5.pngCDel node.pngCDel 3.pngCDel node 1.png
Uniform tiling 63-t02.png
rr{6,3}
3.4.6.4
CDel node 1.pngCDel 6.pngCDel node.pngCDel 3.pngCDel node 1.png
Uniform tiling 73-t02.png
rr{7,3}
3.4.7.4
CDel node 1.pngCDel 7.pngCDel node.pngCDel 3.pngCDel node 1.png
H2 tiling 23i-5.png
rr{∞,3}
3.4.∞.4
CDel node 1.pngCDel infin.pngCDel node.pngCDel 3.pngCDel node 1.png
Semiregular tilings have more than one type of regular polygon.
Uniform tiling 532-t012.png
tr{5,3}
4.6.10
CDel node 1.pngCDel 5.pngCDel node 1.pngCDel 3.pngCDel node 1.png
Uniform tiling 63-t012.png
tr{6,3}
4.6.12
CDel node 1.pngCDel 6.pngCDel node 1.pngCDel 3.pngCDel node 1.png
Uniform tiling 73-t012.png
tr{7,3}
4.6.14
CDel node 1.pngCDel 7.pngCDel node 1.pngCDel 3.pngCDel node 1.png
H2 tiling 23i-7.png
tr{∞,3}
4.6.∞
CDel node 1.pngCDel infin.pngCDel node 1.pngCDel 3.pngCDel node 1.png
Omnitruncated tilings have three or more even-sided regular polygons.

In hyperbolic geometry, a uniform (regular, quasiregular or semiregular) hyperbolic tiling is an edge-to-edge filling of the hyperbolic plane which has regular polygons as faces and is vertex-transitive (transitive on its vertices, isogonal, i.e. there is an isometry mapping any vertex onto any other). It follows that all vertices are congruent, and the tiling has a high degree of rotational and translational symmetry.

Uniform tilings can be identified by their vertex configuration, a sequence of numbers representing the number of sides of the polygons around each vertex. For example 7.7.7 represents the heptagonal tiling which has 3 heptagons around each vertex. It is also regular since all the polygons are the same size, so it can also be given the Schläfli symbol {7,3}.

Uniform tilings may be regular (if also face- and edge-transitive), quasi-regular (if edge-transitive but not face-transitive) or semi-regular (if neither edge- nor face-transitive). For right triangles (p q 2), there are two regular tilings, represented by Schläfli symbol {p,q} and {q,p}.

Wythoff construction[edit]

Example Wythoff construction with right triangles (r=2) and the 7 generator points. Lines to the active mirrors are colored red, yellow, and blue with the 3 nodes opposite them as associated by the Wythoff symbol.

There are an infinite number of uniform tilings based on the Schwarz triangles (p q r) where 1/p + 1/q + 1/r < 1, where p,q,r are each orders of reflection symmetry at three points of the fundamental domain triangle – the symmetry group is a hyperbolic triangle group.

Each symmetry family contains 7 uniform tilings, defined by a Wythoff symbol or Coxeter-Dynkin diagram, 7 representing combinations of 3 active mirrors. An 8th represents an alternation operation, deleting alternate vertices from the highest form with all mirrors active.

Families with r=2 contain regular hyperbolic tilings, defined by a Coxeter group such as [7,3], [8,3], [9,3], ... [5,4], [6,4], ....

Hyperbolic families with r=3 or higher are given by (p q r) and include (4 3 3), (5 3 3), (6 3 3) ... (4 4 3), (5 4 3), ... (4 4 4)....

Hyperbolic triangles (p q r) define compact uniform hyperbolic tilings. In the limit any of p,q or r can be replaced by ∞ which defines a paracompact hyperbolic triangle and creates uniform tilings with either infinite faces (called apeirogons) that converge to a single ideal point, or infinite vertex figure with infinitely many edges diverging from the same ideal point.

More symmetry families can be constructed from fundamental domains that are not triangles.

Selected families of uniform tilings are shown below (using the Poincaré disk model for the hyperbolic plane). Three of them – (7 3 2), (5 4 2), and (4 3 3) – and no others, are minimal in the sense that if any of their defining numbers is replaced by a smaller integer the resulting pattern is either Euclidean or spherical rather than hyperbolic; conversely, any of the numbers can be increased (even to infinity) to generate other hyperbolic patterns.

Each uniform tiling generates a dual uniform tiling, with many of them also given below.

Right triangle domains[edit]

There are infinitely many (p q 2) triangle group families. This article shows the regular tiling up to p,q=8, and uniform tilings in 12 families: (7 3 2), (8 3 2), (5 4 2), (6 4 2), (7 4 2), (8 4 2), (5 5 2), (6 5 2) (6 6 2), (7 7 2), (8 6 2), and (8 8 2).

Regular hyperbolic tilings[edit]

The simplest set of hyperbolic tilings are regular tilings {p,q}, which exist in a matrix with the regular polyhedra and Euclidean tilings. Regular tile {p,q} has a dual tiling {q,p} across the diagonal axis of the table. Self-dual tilings {3,3}, {4,4}, {5,5}, etc. pass down the diagonal of the table.

Spherical (Platonic)/Euclidean/hyperbolic (Poincaré disc: compact/paracompact/noncompact) tessellations with their Schläfli symbol
p \ q 3 4 5 6 7 8 ... ... iπ/λ
3 Uniform tiling 332-t0-1-.png
(tetrahedron)
{3,3}
CDel node 1.pngCDel 3.pngCDel node.pngCDel 3.pngCDel node.png
Uniform tiling 432-t2.png
(octahedron)
{3,4}
CDel node 1.pngCDel 3.pngCDel node.pngCDel 4.pngCDel node.png
Uniform tiling 532-t2.png
(icosahedron)
{3,5}
CDel node 1.pngCDel 3.pngCDel node.pngCDel 5.pngCDel node.png
Uniform tiling 63-t2.png
(deltille)
{3,6}
CDel node 1.pngCDel 3.pngCDel node.pngCDel 6.pngCDel node.png
Uniform tiling 37-t0.png

{3,7}
CDel node 1.pngCDel 3.pngCDel node.pngCDel 7.pngCDel node.png
Uniform tiling 38-t0.png

{3,8}
CDel node 1.pngCDel 3.pngCDel node.pngCDel 8.pngCDel node.png
H2 tiling 23i-4.png

{3,∞}
CDel node 1.pngCDel 3.pngCDel node.pngCDel infin.pngCDel node.png
H2 tiling 23j12-4.png

{3,iπ/λ}
CDel node 1.pngCDel 3.pngCDel node.pngCDel ultra.pngCDel node.png
4 Uniform tiling 432-t0.png
(cube)
{4,3}
CDel node 1.pngCDel 4.pngCDel node.pngCDel 3.pngCDel node.png
Uniform tiling 44-t0.png
(quadrille)
{4,4}
CDel node 1.pngCDel 4.pngCDel node.pngCDel 4.pngCDel node.png
Uniform tiling 45-t0.png

{4,5}
CDel node 1.pngCDel 4.pngCDel node.pngCDel 5.pngCDel node.png
Uniform tiling 46-t0.png

{4,6}
CDel node 1.pngCDel 4.pngCDel node.pngCDel 6.pngCDel node.png
Uniform tiling 47-t0.png

{4,7}
CDel node 1.pngCDel 4.pngCDel node.pngCDel 7.pngCDel node.png
Uniform tiling 48-t0.png

{4,8}
CDel node 1.pngCDel 4.pngCDel node.pngCDel 8.pngCDel node.png
H2 tiling 24i-4.png

{4,∞}
CDel node 1.pngCDel 4.pngCDel node.pngCDel infin.pngCDel node.png
{4,iπ/λ}
CDel node 1.pngCDel 4.pngCDel node.pngCDel ultra.pngCDel node.png
5 Uniform tiling 532-t0.png
(dodecahedron)
{5,3}
CDel node 1.pngCDel 5.pngCDel node.pngCDel 3.pngCDel node.png
Uniform tiling 54-t0.png

{5,4}
CDel node 1.pngCDel 5.pngCDel node.pngCDel 4.pngCDel node.png
Uniform tiling 55-t0.png

{5,5}
CDel node 1.pngCDel 5.pngCDel node.pngCDel 5.pngCDel node.png
Uniform tiling 56-t0.png

{5,6}
CDel node 1.pngCDel 5.pngCDel node.pngCDel 6.pngCDel node.png
Uniform tiling 57-t0.png

{5,7}
CDel node 1.pngCDel 5.pngCDel node.pngCDel 7.pngCDel node.png
Uniform tiling 58-t0.png

{5,8}
CDel node 1.pngCDel 5.pngCDel node.pngCDel 8.pngCDel node.png
H2 tiling 25i-4.png

{5,∞}
CDel node 1.pngCDel 5.pngCDel node.pngCDel infin.pngCDel node.png
{5,iπ/λ}
CDel node 1.pngCDel 5.pngCDel node.pngCDel ultra.pngCDel node.png
6 Uniform tiling 63-t0.png
(hextille)
{6,3}
CDel node 1.pngCDel 6.pngCDel node.pngCDel 3.pngCDel node.png
Uniform tiling 64-t0.png

{6,4}
CDel node 1.pngCDel 6.pngCDel node.pngCDel 4.pngCDel node.png
Uniform tiling 65-t0.png

{6,5}
CDel node 1.pngCDel 6.pngCDel node.pngCDel 5.pngCDel node.png
Uniform tiling 66-t2.png

{6,6}
CDel node 1.pngCDel 6.pngCDel node.pngCDel 6.pngCDel node.png
Uniform tiling 67-t0.png

{6,7}
CDel node 1.pngCDel 6.pngCDel node.pngCDel 7.pngCDel node.png
Uniform tiling 68-t0.png

{6,8}
CDel node 1.pngCDel 6.pngCDel node.pngCDel 8.pngCDel node.png
H2 tiling 26i-4.png

{6,∞}
CDel node 1.pngCDel 6.pngCDel node.pngCDel infin.pngCDel node.png
{6,iπ/λ}
CDel node 1.pngCDel 6.pngCDel node.pngCDel ultra.pngCDel node.png
7 Uniform tiling 73-t0.png
{7,3}
CDel node 1.pngCDel 7.pngCDel node.pngCDel 3.pngCDel node.png
Uniform tiling 74-t0.png
{7,4}
CDel node 1.pngCDel 7.pngCDel node.pngCDel 4.pngCDel node.png
Uniform tiling 75-t0.png
{7,5}
CDel node 1.pngCDel 7.pngCDel node.pngCDel 5.pngCDel node.png
Uniform tiling 76-t0.png
{7,6}
CDel node 1.pngCDel 7.pngCDel node.pngCDel 6.pngCDel node.png
Uniform tiling 77-t2.png
{7,7}
CDel node 1.pngCDel 7.pngCDel node.pngCDel 7.pngCDel node.png
Uniform tiling 78-t0.png
{7,8}
CDel node 1.pngCDel 7.pngCDel node.pngCDel 8.pngCDel node.png
H2 tiling 27i-4.png
{7,∞}
CDel node 1.pngCDel 7.pngCDel node.pngCDel infin.pngCDel node.png
{7,iπ/λ}
CDel node 1.pngCDel 7.pngCDel node.pngCDel ultra.pngCDel node.png
8 Uniform tiling 83-t0.png
{8,3}
CDel node 1.pngCDel 8.pngCDel node.pngCDel 3.pngCDel node.png
Uniform tiling 84-t0.png
{8,4}
CDel node 1.pngCDel 8.pngCDel node.pngCDel 4.pngCDel node.png
Uniform tiling 85-t0.png
{8,5}
CDel node 1.pngCDel 8.pngCDel node.pngCDel 5.pngCDel node.png
Uniform tiling 86-t0.png
{8,6}
CDel node 1.pngCDel 8.pngCDel node.pngCDel 6.pngCDel node.png
Uniform tiling 87-t0.png
{8,7}
CDel node 1.pngCDel 8.pngCDel node.pngCDel 7.pngCDel node.png
Uniform tiling 88-t2.png
{8,8}
CDel node 1.pngCDel 8.pngCDel node.pngCDel 8.pngCDel node.png
H2 tiling 28i-4.png
{8,∞}
CDel node 1.pngCDel 8.pngCDel node.pngCDel infin.pngCDel node.png
{8,iπ/λ}
CDel node 1.pngCDel 8.pngCDel node.pngCDel ultra.pngCDel node.png
...
H2 tiling 23i-1.png
{∞,3}
CDel node 1.pngCDel infin.pngCDel node.pngCDel 3.pngCDel node.png
H2 tiling 24i-1.png
{∞,4}
CDel node 1.pngCDel infin.pngCDel node.pngCDel 4.pngCDel node.png
H2 tiling 25i-1.png
{∞,5}
CDel node 1.pngCDel infin.pngCDel node.pngCDel 5.pngCDel node.png
H2 tiling 26i-1.png
{∞,6}
CDel node 1.pngCDel infin.pngCDel node.pngCDel 6.pngCDel node.png
H2 tiling 27i-1.png
{∞,7}
CDel node 1.pngCDel infin.pngCDel node.pngCDel 7.pngCDel node.png
H2 tiling 28i-1.png
{∞,8}
CDel node 1.pngCDel infin.pngCDel node.pngCDel 8.pngCDel node.png
H2 tiling 2ii-1.png
{∞,∞}
CDel node 1.pngCDel infin.pngCDel node.pngCDel infin.pngCDel node.png
{∞,iπ/λ}
CDel node 1.pngCDel infin.pngCDel node.pngCDel ultra.pngCDel node.png
...
iπ/λ H2 tiling 23j12-1.png
{iπ/λ,3}
CDel node 1.pngCDel ultra.pngCDel node.pngCDel 3.pngCDel node.png
{iπ/λ,4}
CDel node 1.pngCDel ultra.pngCDel node.pngCDel 4.pngCDel node.png
{iπ/λ,5}
CDel node 1.pngCDel ultra.pngCDel node.pngCDel 5.pngCDel node.png
{iπ/λ,6}
CDel node 1.pngCDel ultra.pngCDel node.pngCDel 6.pngCDel node.png
{iπ/λ,7}
CDel node 1.pngCDel ultra.pngCDel node.pngCDel 7.pngCDel node.png
{iπ/λ,8}
CDel node 1.pngCDel ultra.pngCDel node.pngCDel 8.pngCDel node.png
{iπ/λ,∞}
CDel node 1.pngCDel ultra.pngCDel node.pngCDel infin.pngCDel node.png
{iπ/λ,iπ/λ}
CDel node 1.pngCDel ultra.pngCDel node.pngCDel ultra.pngCDel node.png

(7 3 2)[edit]

The (7 3 2) triangle group, Coxeter group [7,3], orbifold (*732) contains these uniform tilings:

(8 3 2)[edit]

The (8 3 2) triangle group, Coxeter group [8,3], orbifold (*832) contains these uniform tilings:

(5 4 2)[edit]

The (5 4 2) triangle group, Coxeter group [5,4], orbifold (*542) contains these uniform tilings:

(6 4 2)[edit]

The (6 4 2) triangle group, Coxeter group [6,4], orbifold (*642) contains these uniform tilings. Because all the elements are even, each uniform dual tiling one represents the fundamental domain of a reflective symmetry: *3333, *662, *3232, *443, *222222, *3222, and *642 respectively. As well, all 7 uniform tiling can be alternated, and those have duals as well.

(7 4 2)[edit]

The (7 4 2) triangle group, Coxeter group [7,4], orbifold (*742) contains these uniform tilings:

Uniform heptagonal/square tilings
Symmetry: [7,4], (*742) [7,4]+, (742) [7+,4], (7*2) [7,4,1+], (*772)
CDel node 1.pngCDel 7.pngCDel node.pngCDel 4.pngCDel node.png CDel node 1.pngCDel 7.pngCDel node 1.pngCDel 4.pngCDel node.png CDel node.pngCDel 7.pngCDel node 1.pngCDel 4.pngCDel node.png CDel node.pngCDel 7.pngCDel node 1.pngCDel 4.pngCDel node 1.png CDel node.pngCDel 7.pngCDel node.pngCDel 4.pngCDel node 1.png CDel node 1.pngCDel 7.pngCDel node.pngCDel 4.pngCDel node 1.png CDel node 1.pngCDel 7.pngCDel node 1.pngCDel 4.pngCDel node 1.png CDel node h.pngCDel 7.pngCDel node h.pngCDel 4.pngCDel node h.png CDel node h.pngCDel 7.pngCDel node h.pngCDel 4.pngCDel node.png CDel node.pngCDel 7.pngCDel node.pngCDel 4.pngCDel node h.png
Uniform tiling 74-t0.png Uniform tiling 74-t01.png Uniform tiling 74-t1.png Uniform tiling 74-t12.png Uniform tiling 74-t2.png Uniform tiling 74-t02.png Uniform tiling 74-t012.png Uniform tiling 74-snub.png Uniform tiling 74-h01.png Uniform tiling 77-t0.png
{7,4} t{7,4} r{7,4} 2t{7,4}=t{4,7} 2r{7,4}={4,7} rr{7,4} tr{7,4} sr{7,4} s{7,4} h{4,7}
Uniform duals
CDel node f1.pngCDel 7.pngCDel node.pngCDel 4.pngCDel node.png CDel node f1.pngCDel 7.pngCDel node f1.pngCDel 4.pngCDel node.png CDel node.pngCDel 7.pngCDel node f1.pngCDel 4.pngCDel node.png CDel node.pngCDel 7.pngCDel node f1.pngCDel 4.pngCDel node f1.png CDel node.pngCDel 7.pngCDel node.pngCDel 4.pngCDel node f1.png CDel node f1.pngCDel 7.pngCDel node.pngCDel 4.pngCDel node f1.png CDel node f1.pngCDel 7.pngCDel node f1.pngCDel 4.pngCDel node f1.png CDel node fh.pngCDel 7.pngCDel node fh.pngCDel 4.pngCDel node fh.png CDel node fh.pngCDel 7.pngCDel node fh.pngCDel 4.pngCDel node.png CDel node.pngCDel 7.pngCDel node.pngCDel 4.pngCDel node fh.png
Uniform tiling 74-t2.png Hyperbolic domains 772.png Ord74 qreg rhombic til.png Order4 heptakis heptagonal til.png Uniform tiling 74-t0.png Deltoidal tetraheptagonal til.png Hyperbolic domains 742.png Uniform tiling 77-t2.png
V74 V4.14.14 V4.7.4.7 V7.8.8 V47 V4.4.7.4 V4.8.14 V3.3.4.3.7 V3.3.7.3.7 V77

(8 4 2)[edit]

The (8 4 2) triangle group, Coxeter group [8,4], orbifold (*842) contains these uniform tilings. Because all the elements are even, each uniform dual tiling one represents the fundamental domain of a reflective symmetry: *4444, *882, *4242, *444, *22222222, *4222, and *842 respectively. As well, all 7 uniform tiling can be alternated, and those have duals as well.

(5 5 2)[edit]

The (5 5 2) triangle group, Coxeter group [5,5], orbifold (*552) contains these uniform tilings:

(6 5 2)[edit]

The (6 5 2) triangle group, Coxeter group [6,5], orbifold (*652) contains these uniform tilings:

(6 6 2)[edit]

The (6 6 2) triangle group, Coxeter group [6,6], orbifold (*662) contains these uniform tilings: