Polyhedric figures,
perhaps drawn by Leonardo Da Vinci , illustrated the " De Divina
Proportione" by Luca Pacioli , in the XV century. Luca Pacioli
reawakened interest in them , shortly after the great painter Piero
della Francesca , his contemporary and countryman , who wrote an interesting
treatise De corporibus regularibus, a treatise which remained as a manuscript
and which Pacioli translated publishing it in his aforementioned work.
The five regular
polyhedrons once again took on a cosmic role with Keppler (1571-1630),
who,in one of his first works maintained that the relationship of the
distances of the six known planets from the sun , could be determined
according to the properties of the so-called Platonic bodies. The study
of the regular polyhedrons thus became part of the history of mathematics
and Keppler was credited with the discovery of the stellar dodecahedron.
Indeed, a stellar dodecahedron mosaic exists in the floor of the basilica
of Saint Mark in Venice, created in all probability by Paolo Uccello.
In 1752 Eulero established
the fundamental relationship between the number of vertices ,corners,
and faces of a polyhedron. Using the dodecahedron which is composed
of twelve faces and twenty vertices as an example ,summing the number
of vertices (20) and the faces (12) and subtracting two, one obtains
the number of corners (30). Icosahedron: 12 vertices + 20 faces - 2
faces = 30 corners. Octahedron: 6 Vertices + 8 - 2 faces =12 corners.
Hexahedron: 8 vertices +6-2 faces =12 corners. Tetrahedron: 4 vertices
+ 4 - 2 faces = 6 corners.
Shapes inspired
by regular polyhedrons abound in modern art and design too, from the
works of Escher through modular architecture to the objects of Munari.
Giuseppe
Mencarini
Bibl.
Annuario Est 1976, Mondadori -MI- / Diz. Enc. Utet 1970/ A. Marcolli,
Teoria del campo 2