Gian Marco Todesco
This short computer graphics animation presents the regular 120-cell: a four dimensional polytope composed of 120 dodecahedra and also known as the hyperdodecahedron or hecatonicosachoron. The figure is built up through a sequence of subsequent foldings: 5 segments form a pentagon, 12 pentagons form a dodecahedron and eventually 120 dodecahedra form the 120-cell. The 4D shape is visualized through its three dimensional "shadow".
We used counting of polyhedra to celebrate the 150th Anniversary of Italy's national Unity. The first version of this video has been presented at the Genova Science Festival. Corrado Falcolini worked out most of the the math involved, and a first study-version of this video in Mathematica. Thanks to Laura Tedeschini Lalli, scientific supervisor of Laboratorio di Matematica (www.formulas.it), Università Roma Tre for pointing out some subtle discrepancies. Thanks to Roberto D'Autilia for the starting ideas.