Friday, 13 June 2014 11:42

## E2-37: PLATONIC SOLIDS AND KEPLER

• ID Code: E2-37
• Purpose: Visualize the Platonic solids and Kepler's dream for using them to explain planetary orbits.
• Description:

There are five three-dimensional Platonic solids. The faces of a Platonic solid are identical regular polygons and all vertex angles are equal. These solids are:

Name..........Number of faces

Tetrahedron.......4
Cube...................6
Octahedron.........8
Dodecahedron....12
Icosahedron........20

As illustrated in the accompanying transparency, Kepler spent most of his life assuming that planetary orbits were circular and trying to use Platonic solids to deduce their radii. Only much later, after he gave up his dream, did he discover his true laws for planetary motion. Although Kepler's original dream was a failure, much of the same mathematical/geometrical spirit prevails in our modern attempts to explain the fundamental nature of matter via symmetry, group theory, field theory, the geometry of various higher dimensional manifolds, and string theory.

• Availability: Available
• Loc codes: E2

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• #### E2-37: PLATONIC SOLIDS AND KEPLER

Visualize the Platonic solids and Kepler's dream for using them to explain planetary orbits. Read More
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