Truncated tetrahexagonal tiling

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Truncated tetrahexagonal tiling
Truncated tetrahexagonal tiling
Poincaré disk model of the hyperbolic plane
Type Hyperbolic uniform tiling
Vertex configuration 4.8.12
Schläfli symbol tr{6,4} or
Wythoff symbol 2 6 4 |
Coxeter diagram CDel node 1.pngCDel 6.pngCDel node 1.pngCDel 4.pngCDel node 1.png or CDel node 1.pngCDel split1-64.pngCDel nodes 11.png
Symmetry group [6,4], (*642)
Dual Order-4-6 kisrhombille tiling
Properties Vertex-transitive

In geometry, the truncated tetrahexagonal tiling is a semiregular tiling of the hyperbolic plane. There are one square, one octagon, and one dodecagon on each vertex. It has Schläfli symbol of tr{6,4}.

Dual tiling[edit]

H2checkers 246.png Hyperbolic domains 642.png
The dual tiling is called an order-4-6 kisrhombille tiling, made as a complete bisection of the order-4 hexagonal tiling, here with triangles shown in alternating colors. This tiling represents the fundamental triangular domains of [6,4] (*642) symmetry.

Related polyhedra and tilings[edit]

From a Wythoff construction there are fourteen hyperbolic uniform tilings that can be based from the regular order-4 hexagonal tiling.

Drawing the tiles colored as red on the original faces, yellow at the original vertices, and blue along the original edges, there are 7 forms with full [6,4] symmetry, and 7 with subsymmetry.

Symmetry[edit]

Truncated tetrahexagonal tiling with mirror lines in green, red, and blue: CDel node c3.pngCDel 6.pngCDel node c1.pngCDel 4.pngCDel node c2.png
Symmetry diagrams for small index subgroups of [6,4], shown in a hexagonal translational cell within a {6,6} tiling, with a fundamental domain in yellow.

The dual of the tiling represents the fundamental domains of (*642) orbifold symmetry. From [6,4] symmetry, there are 15 small index subgroup by mirror removal and alternation operators. Mirrors can be removed if its branch orders are all even, and cuts neighboring branch orders in half. Removing two mirrors leaves a half-order gyration point where the removed mirrors met. In these images unique mirrors are colored red, green, and blue, and alternatedly colored triangles show the location of gyration points. The [6+,4+], (32×) subgroup has narrow lines representing glide reflections. The subgroup index-8 group, [1+,6,1+,4,1+] (3232) is the commutator subgroup of [6,4].

Larger subgroup constructed as [6,4*], removing the gyration points of [6,4+], (3*22), index 6 becomes (*3333), and [6*,4], removing the gyration points of [6+,4], (2*33), index 12 as (*222222). Finally their direct subgroups [6,4*]+, [6*,4]+, subgroup indices 12 and 24 respectively, can be given in orbifold notation as (3333) and (222222).

See also[edit]

References[edit]

  • John H. Conway, Heidi Burgiel, Chaim Goodman-Strass, The Symmetries of Things 2008, ISBN 978-1-56881-220-5 (Chapter 19, The Hyperbolic Archimedean Tessellations)
  • "Chapter 10: Regular honeycombs in hyperbolic space". The Beauty of Geometry: Twelve Essays. Dover Publications. 1999. ISBN 0-486-40919-8. LCCN 99035678. 

External links[edit]