Golden ratio
Videos
In mathematics, two quantities are in the golden ratio if their ratio is the same as the ratio of their sum to the larger of the two quantities. Expressed algebraically, for quantities a and b
Michael Maestlin, the first to write a decimal approximation of the ratio
Dan Shechtman demonstrates quasicrystals at the NIST in 1985 using a Zometoy model.
Da Vinci's illustration of a dodecahedron from Pacioli's Divina proportione (1509)
Detail of the saucer plant, Aeonium tabuliforme, showing the multiple spiral arrangement (parastichy)
Cube
Videos
A cube is a three-dimensional solid object in geometry. It has eight vertices and twelve straight edges of the same length, so that these edges form six square faces of the same size. It is an example
Table salt cubic crystals
The Norwegian CubeSat
Sketch of a cube by Johannes Kepler
Kepler's Platonic solid model of the Solar System