Order-5 hexagonal tiling honeycomb

Perspective projection view
from center of Poincaré disk model
Type Hyperbolic regular honeycomb
Paracompact uniform honeycomb
Schläfli symbol {6,3,5}
Coxeter-Dynkin diagrams
Cells {6,3}
Faces hexagon {6}
Edge figure pentagon {5}
Vertex figure icosahedron
Dual Order-6 dodecahedral honeycomb
Coxeter group , [5,3,6]
Properties Regular

In the field of hyperbolic geometry, the order-5 hexagonal tiling honeycomb arises as one of 11 regular paracompact honeycombs in 3-dimensional hyperbolic space. It is paracompact because it has cells composed of an infinite number of faces. Each cell consists of a hexagonal tiling whose vertices lie on a horosphere, a flat plane in hyperbolic space that approaches a single ideal point at infinity.

The Schläfli symbol of the order-5 hexagonal tiling honeycomb is {6,3,5}. Since that of the hexagonal tiling is {6,3}, this honeycomb has five such hexagonal tilings meeting at each edge. Since the Schläfli symbol of the icosahedron is {3,5}, the vertex figure of this honeycomb is an icosahedron. Thus, 20 hexagonal tilings meet at each vertex of this honeycomb.[1]

A geometric honeycomb is a space-filling of polyhedral or higher-dimensional cells, so that there are no gaps. It is an example of the more general mathematical tiling or tessellation in any number of dimensions.

Honeycombs are usually constructed in ordinary Euclidean ("flat") space, like the convex uniform honeycombs. They may also be constructed in non-Euclidean spaces, such as hyperbolic uniform honeycombs. Any finite uniform polytope can be projected to its circumsphere to form a uniform honeycomb in spherical space.

Symmetry

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A lower-symmetry construction of index 120, [6,(3,5)*], exists with regular dodecahedral fundamental domains, and an icosahedral Coxeter-Dynkin diagram with 6 axial infinite-order (ultraparallel) branches.

Images

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The order-5 hexagonal tiling honeycomb is similar to the 2D hyperbolic regular paracompact order-5 apeirogonal tiling, {∞,5}, with five apeirogonal faces meeting around every vertex.

 
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The order-5 hexagonal tiling honeycomb is a regular hyperbolic honeycomb in 3-space, and one of 11 which are paracompact.

11 paracompact regular honeycombs
 
{6,3,3}
 
{6,3,4}
 
{6,3,5}
 
{6,3,6}
 
{4,4,3}
 
{4,4,4}
 
{3,3,6}
 
{4,3,6}
 
{5,3,6}
 
{3,6,3}
 
{3,4,4}

There are 15 uniform honeycombs in the [6,3,5] Coxeter group family, including this regular form, and its regular dual, the order-6 dodecahedral honeycomb.

[6,3,5] family honeycombs
{6,3,5} r{6,3,5} t{6,3,5} rr{6,3,5} t0,3{6,3,5} tr{6,3,5} t0,1,3{6,3,5} t0,1,2,3{6,3,5}
               
             
{5,3,6} r{5,3,6} t{5,3,6} rr{5,3,6} 2t{5,3,6} tr{5,3,6} t0,1,3{5,3,6} t0,1,2,3{5,3,6}

The order-5 hexagonal tiling honeycomb has a related alternation honeycomb, represented by             , with icosahedron and triangular tiling cells.

It is a part of sequence of regular hyperbolic honeycombs of the form {6,3,p}, with hexagonal tiling facets:

{6,3,p} honeycombs
Space H3
Form Paracompact Noncompact
Name {6,3,3} {6,3,4} {6,3,5} {6,3,6} {6,3,7} {6,3,8} ... {6,3,∞}
Coxeter
       
       
               
     
       
               
     
       
               
      
       
      
 
Image              
Vertex
figure
{3,p}
     
 
{3,3}
     
 
{3,4}
     
   
 
{3,5}
     
 
{3,6}
     
   
 
{3,7}
     
 
{3,8}
     
    
 
{3,∞}
     
    

It is also part of a sequence of regular polychora and honeycombs with icosahedral vertex figures:

{p,3,5} polytopes
Space S3 H3
Form Finite Compact Paracompact Noncompact
Name {3,3,5}
       
{4,3,5}
       
{5,3,5}
       
{6,3,5}
       
{7,3,5}
       
{8,3,5}
       
... {∞,3,5}
       
Image              
Cells  
{3,3}
     
 
{4,3}
     
 
{5,3}
     
 
{6,3}
     
 
{7,3}
     
 
{8,3}
     
 
{∞,3}
     

Rectified order-5 hexagonal tiling honeycomb

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Rectified order-5 hexagonal tiling honeycomb
Type Paracompact uniform honeycomb
Schläfli symbols r{6,3,5} or t1{6,3,5}
Coxeter diagrams        
            
Cells {3,5}  
r{6,3} or h2{6,3}
  
Faces triangle {3}
hexagon {6}
Vertex figure  
pentagonal prism
Coxeter groups  , [5,3,6]
 , [5,3[3]]
Properties Vertex-transitive, edge-transitive

The rectified order-5 hexagonal tiling honeycomb, t1{6,3,5},         has icosahedron and trihexagonal tiling facets, with a pentagonal prism vertex figure.

 

It is similar to the 2D hyperbolic infinite-order square tiling, r{∞,5} with pentagon and apeirogonal faces. All vertices are on the ideal surface.

 
r{p,3,5}
Space S3 H3
Form Finite Compact Paracompact Noncompact
Name r{3,3,5}
       
r{4,3,5}
       
     
r{5,3,5}
       
r{6,3,5}
       
     
r{7,3,5}
       
... r{∞,3,5}
       
      
Image        
Cells
 
{3,5}
     
 
r{3,3}
     
 
r{4,3}
     
 
r{5,3}
     
 
r{6,3}
     
 
r{7,3}
     
 
r{∞,3}
     

Truncated order-5 hexagonal tiling honeycomb

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Truncated order-5 hexagonal tiling honeycomb
Type Paracompact uniform honeycomb
Schläfli symbol t{6,3,5} or t0,1{6,3,5}
Coxeter diagram        
Cells {3,5}  
t{6,3}  
Faces triangle {3}
dodecagon {12}
Vertex figure  
pentagonal pyramid
Coxeter groups  , [5,3,6]
Properties Vertex-transitive

The truncated order-5 hexagonal tiling honeycomb, t0,1{6,3,5},         has icosahedron and truncated hexagonal tiling facets, with a pentagonal pyramid vertex figure.

 

Bitruncated order-5 hexagonal tiling honeycomb

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Bitruncated order-5 hexagonal tiling honeycomb
Type Paracompact uniform honeycomb
Schläfli symbol 2t{6,3,5} or t1,2{6,3,5}
Coxeter diagram        
            
Cells t{3,6}  
t{3,5}  
Faces pentagon {5}
hexagon {6}
Vertex figure  
digonal disphenoid
Coxeter groups  , [5,3,6]
 , [5,3[3]]
Properties Vertex-transitive

The bitruncated order-5 hexagonal tiling honeycomb, t1,2{6,3,5},         has hexagonal tiling and truncated icosahedron facets, with a digonal disphenoid vertex figure.

 

Cantellated order-5 hexagonal tiling honeycomb

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Cantellated order-5 hexagonal tiling honeycomb
Type Paracompact uniform honeycomb
Schläfli symbol rr{6,3,5} or t0,2{6,3,5}
Coxeter diagram        
Cells r{3,5}  
rr{6,3}  
{}x{5}  
Faces triangle {3}
square {4}
pentagon {5}
hexagon {6}
Vertex figure  
wedge
Coxeter groups  , [5,3,6]
Properties Vertex-transitive

The cantellated order-5 hexagonal tiling honeycomb, t0,2{6,3,5},         has icosidodecahedron, rhombitrihexagonal tiling, and pentagonal prism facets, with a wedge vertex figure.

 

Cantitruncated order-5 hexagonal tiling honeycomb

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Cantitruncated order-5 hexagonal tiling honeycomb
Type Paracompact uniform honeycomb
Schläfli symbol tr{6,3,5} or t0,1,2{6,3,5}
Coxeter diagram        
Cells t{3,5}  
tr{6,3}  
{}x{5}  
Faces square {4}
pentagon {5}
hexagon {6}
dodecagon {12}
Vertex figure  
mirrored sphenoid
Coxeter groups  , [5,3,6]
Properties Vertex-transitive

The cantitruncated order-5 hexagonal tiling honeycomb, t0,1,2{6,3,5},         has truncated icosahedron, truncated trihexagonal tiling, and pentagonal prism facets, with a mirrored sphenoid vertex figure.

 

Runcinated order-5 hexagonal tiling honeycomb

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Runcinated order-5 hexagonal tiling honeycomb
Type Paracompact uniform honeycomb
Schläfli symbol t0,3{6,3,5}
Coxeter diagram        
Cells {6,3}  
{5,3}  
{}x{6}  
{}x{5}  
Faces square {4}
pentagon {5}
hexagon {6}
Vertex figure  
irregular triangular antiprism
Coxeter groups  , [5,3,6]
Properties Vertex-transitive

The runcinated order-5 hexagonal tiling honeycomb, t0,3{6,3,5},         has dodecahedron, hexagonal tiling, pentagonal prism, and hexagonal prism facets, with an irregular triangular antiprism vertex figure.

 

Runcitruncated order-5 hexagonal tiling honeycomb

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Runcitruncated order-5 hexagonal tiling honeycomb
Type Paracompact uniform honeycomb
Schläfli symbol t0,1,3{6,3,5}
Coxeter diagram        
Cells t{6,3}  
rr{5,3}  
{}x{5}  
{}x{12}  
Faces triangle {3}
square {4}
pentagon {5}
dodecagon {12}
Vertex figure  
isosceles-trapezoidal pyramid
Coxeter groups  , [5,3,6]
Properties Vertex-transitive

The runcitruncated order-5 hexagonal tiling honeycomb, t0,1,3{6,3,5},         has truncated hexagonal tiling, rhombicosidodecahedron, pentagonal prism, and dodecagonal prism cells, with an isosceles-trapezoidal pyramid vertex figure.

 

Runcicantellated order-5 hexagonal tiling honeycomb

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The runcicantellated order-5 hexagonal tiling honeycomb is the same as the runcitruncated order-6 dodecahedral honeycomb.

Omnitruncated order-5 hexagonal tiling honeycomb

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Omnitruncated order-5 hexagonal tiling honeycomb
Type Paracompact uniform honeycomb
Schläfli symbol t0,1,2,3{6,3,5}
Coxeter diagram        
Cells tr{6,3}  
tr{5,3}  
{}x{10}  
{}x{12}  
Faces square {4}
hexagon {6}
decagon {10}
dodecagon {12}
Vertex figure  
irregular tetrahedron
Coxeter groups  , [5,3,6]
Properties Vertex-transitive

The omnitruncated order-5 hexagonal tiling honeycomb, t0,1,2,3{6,3,5},         has truncated trihexagonal tiling, truncated icosidodecahedron, decagonal prism, and dodecagonal prism facets, with an irregular tetrahedral vertex figure.

 

Alternated order-5 hexagonal tiling honeycomb

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Alternated order-5 hexagonal tiling honeycomb
Type Paracompact uniform honeycomb
Semiregular honeycomb
Schläfli symbol h{6,3,5}
Coxeter diagram             
Cells {3[3]}  
{3,5}  
Faces triangle {3}
Vertex figure  
truncated icosahedron
Coxeter groups  , [5,3[3]]
Properties Vertex-transitive, edge-transitive, quasiregular

The alternated order-5 hexagonal tiling honeycomb, h{6,3,5},             , has triangular tiling and icosahedron facets, with a truncated icosahedron vertex figure. It is a quasiregular honeycomb.

Cantic order-5 hexagonal tiling honeycomb

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Cantic order-5 hexagonal tiling honeycomb
Type Paracompact uniform honeycomb
Schläfli symbol h2{6,3,5}
Coxeter diagram             
Cells h2{6,3}  
t{3,5}  
r{5,3}  
Faces triangle {3}
pentagon {5}
hexagon {6}
Vertex figure  
triangular prism
Coxeter groups  , [5,3[3]]
Properties Vertex-transitive

The cantic order-5 hexagonal tiling honeycomb, h2{6,3,5},             , has trihexagonal tiling, truncated icosahedron, and icosidodecahedron facets, with a triangular prism vertex figure.

Runcic order-5 hexagonal tiling honeycomb

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Runcic order-5 hexagonal tiling honeycomb
Type Paracompact uniform honeycomb
Schläfli symbol h3{6,3,5}
Coxeter diagram             
Cells {3[3]}  
rr{5,3}  
{5,3}  
{}x{3}  
Faces triangle {3}
square {4}
pentagon {5}
Vertex figure  
triangular cupola
Coxeter groups  , [5,3[3]]
Properties Vertex-transitive

The runcic order-5 hexagonal tiling honeycomb, h3{6,3,5},             , has triangular tiling, rhombicosidodecahedron, dodecahedron, and triangular prism facets, with a triangular cupola vertex figure.

Runcicantic order-5 hexagonal tiling honeycomb

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Runcicantic order-5 hexagonal tiling honeycomb
Type Paracompact uniform honeycomb
Schläfli symbol h2,3{6,3,5}
Coxeter diagram             
Cells h2{6,3}  
tr{5,3}  
t{5,3}  
{}x{3}  
Faces triangle {3}
square {4}
hexagon {6}
decagon {10}
Vertex figure  
rectangular pyramid
Coxeter groups  , [5,3[3]]
Properties Vertex-transitive

The runcicantic order-5 hexagonal tiling honeycomb, h2,3{6,3,5},             , has trihexagonal tiling, truncated icosidodecahedron, truncated dodecahedron, and triangular prism facets, with a rectangular pyramid vertex figure.

See also

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References

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  1. ^ Coxeter The Beauty of Geometry, 1999, Chapter 10, Table III
  • Coxeter, Regular Polytopes, 3rd. ed., Dover Publications, 1973. ISBN 0-486-61480-8. (Tables I and II: Regular polytopes and honeycombs, pp. 294–296)
  • The Beauty of Geometry: Twelve Essays (1999), Dover Publications, LCCN 99-35678, ISBN 0-486-40919-8 (Chapter 10, Regular Honeycombs in Hyperbolic Space) Table III
  • Jeffrey R. Weeks The Shape of Space, 2nd edition ISBN 0-8247-0709-5 (Chapter 16-17: Geometries on Three-manifolds I, II)
  • Norman Johnson Uniform Polytopes, Manuscript
    • N.W. Johnson: The Theory of Uniform Polytopes and Honeycombs, Ph.D. Dissertation, University of Toronto, 1966
    • N.W. Johnson: Geometries and Transformations, (2018) Chapter 13: Hyperbolic Coxeter groups