Classes of Noble Polyhedra
There are four main classes of noble polyhedra:
- Regular polyhedra are also noble.
- Disphenoid tetrahedra. These and the Platonic solids are the only convex noble polyhedra.
- Crown polyhedra or Stephanoids. An infinite series of toroids.
- A variety of miscellaneous examples. It is not known whether there are finitely many, and if so how many might remain to be discovered.
If we allow some of Grünbaum's stranger constructions as polyhedra, then we have two more infinite series of toroids:
- Wreath polyhedra. These have triangular faces in coplanar pairs which share an edge.
- V-faced polyhedra. These have vertices in coincident pairs, and degenerate faces.
Read more about this topic: Noble Polyhedron
Famous quotes containing the words classes of, classes and/or noble:
“There are two classes of men called poets. The one cultivates life, the other art,... one satisfies hunger, the other gratifies the palate.”
—Henry David Thoreau (18171862)
“Solidity, caution, integrity, efficiency. Lack of imagination, hypocrisy. These qualities characterize the middle classes in every country, but in England they are national characteristics.”
—E.M. (Edward Morgan)
“The light by which we see in this world comes out from the soul of the observer. Wherever any noble sentiment dwelt, it made the faces and houses around to shine. Nay, the powers of this busy brain are miraculous and illimitable.”
—Ralph Waldo Emerson (18031882)