order-5 dodecahedral honeycomb#Rectified order-5 dodecahedral honeycomb
{{Short description|Regular tiling of hyperbolic 3-space}}
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!bgcolor=#e7dcc3 colspan=2|Order-5 dodecahedral honeycomb | |
colspan=2 align=center|320px Perspective projection view from center of Poincaré disk model | |
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|bgcolor=#e7dcc3|Type | Hyperbolic regular honeycomb Uniform hyperbolic honeycomb |
bgcolor=#e7dcc3|Schläfli symbol | {{math|{5,3,5} t{{sub|0}}{5,3,5} }} |
bgcolor=#e7dcc3|Coxeter-Dynkin diagram | {{CDD|node_1|5|node|3|node|5|node}} |
bgcolor=#e7dcc3|Cells | {{math|{5,3} }} (regular dodecahedron) 40px |
bgcolor=#e7dcc3|Faces | {{math|{5} }} (pentagon) |
bgcolor=#e7dcc3|Edge figure | {{math|{5} }} (pentagon) |
bgcolor=#e7dcc3|Vertex figure | 80px icosahedron |
bgcolor=#e7dcc3|Dual | Self-dual |
bgcolor=#e7dcc3|Coxeter group | {{math|{{overline|K}}{{sub|3}}, [5,3,5]}} |
bgcolor=#e7dcc3|Properties | Regular |
In hyperbolic geometry, the order-5 dodecahedral honeycomb is one of four compact regular space-filling tessellations (or honeycombs) in hyperbolic 3-space. With Schläfli symbol {{math|{5,3,5},}} it has five dodecahedral cells around each edge, and each vertex is surrounded by twenty dodecahedra. Its vertex figure is an icosahedron.
{{Honeycomb}}
Description
The dihedral angle of a Euclidean regular dodecahedron is ~116.6°, so no more than three of them can fit around an edge in Euclidean 3-space. In hyperbolic space, however, the dihedral angle is smaller than it is in Euclidean space, and depends on the size of the figure; the smallest possible dihedral angle is 60°, for an ideal hyperbolic regular dodecahedron with infinitely long edges. The dodecahedra in this dodecahedral honeycomb are sized so that all of their dihedral angles are exactly 72°.
Images
File:H2 tiling 255-1.png, {5,5}]]
Related polytopes and honeycombs
There are four regular compact honeycombs in 3D hyperbolic space:
{{Regular compact H3 honeycombs}}
There is another honeycomb in hyperbolic 3-space called the order-4 dodecahedral honeycomb, {5,3,4}, which has only four dodecahedra per edge. These honeycombs are also related to the 120-cell which can be considered as a honeycomb in positively curved space (the surface of a 4-dimensional sphere), with three dodecahedra on each edge, {5,3,3}. Lastly the dodecahedral ditope, {5,3,2} exists on a 3-sphere, with 2 hemispherical cells.
There are nine uniform honeycombs in the [5,3,5] Coxeter group family, including this regular form. Also the bitruncated form, t1,2{5,3,5}, {{CDD|node|5|node_1|3|node_1|5|node}}, of this honeycomb has all truncated icosahedron cells.
{{535 family}}
The Seifert–Weber space is a compact manifold that can be formed as a quotient space of the order-5 dodecahedral honeycomb.
This honeycomb is a part of a sequence of polychora and honeycombs with icosahedron vertex figures:
{{Icosahedral vertex figure tessellations}}
This honeycomb is a part of a sequence of regular polytopes and honeycombs with dodecahedral cells:
{{Dodecahedral_tessellations small}}
{{Symmetric2_tessellations}}
= Rectified order-5 dodecahedral honeycomb =
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!bgcolor=#e7dcc3 colspan=2|Rectified order-5 dodecahedral honeycomb
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