Flying Further into the K5 Galaxy
An extension to Chapter XVI of 'Adventures Among The Toroids' by B.M.Stewart 



3. Threaded examples involving dodecahedra


Copies of J92 excavated from K5 can be linked with dodecahedra (D5). One vertex of this D5 lies on a hexagonal face of K5. This vertex can be removed by excavating G3 (link). Up to three independent tunnels can be formed by excavating J92(D5G3-E)J92 from K5. A ring can be formed of five dodecahedral links. Neighbouring copies of D5 now share a common edge, this is resolved by adding J63. The toroid K5 / [J92D5G3-EJ63]5C can then be generated



K5 / [J92D5G3-EJ63]5C  Genus p=5

The hole in this ring can be enlarged by excavating a further copy of G3 from each D5, this hole is then large enough to allow a specifically sequenced S* to pass through to form the threaded toroid
K5 / [J92D5G3-2EJ63]5C, S*.


K5 / [J92D5G3-2EJ63]5C, S*   Genus p=6
.

The connection between D5 and J63 means that the J92 excavations can be omitted. In this case each J63 can be connected to the K5 with a Q5 to form the threaded toroid K5 / [Q5J63D5G3-2E]5C, S*


K5 / [Q5J63D5G3-2E]5C, S*   Genus p=6


It is this toroid which allows the proof of the validity of this family. The triangular faces of J63 are coincident with the faces of S5 in section 2.1. Two facing pentagonal faces have their nearest vertices 1 edge length apart (as they are neighbouring S5 vertices), the two vertices shared with the Q5 are Φ units apart (as they are also vertices of J91). On page 187 Stewart dissects E5 into 6J91 • (P4) • 12Y5 • 8G3. The top vertices of our copies of J63 are the top vertices of Y5 in this dissection, they are thus also separated by Φ units. Thus, pentagons can be inserted between the two copies of J63 to generate 5-5-5 vertices which show the pentagons are faces of a dodecahedron.



Separation of J63 showing validity of connection by pentagonal faces.