In it, each of the six sides has a clear and simple to understand photon polarization state, either of:
- diagonal up/diagonal down
- rotation clockwise/counterclockwise
The sphere clearly suggests for example that a rotational or diagonal polarizations are the combination of left/right with the correct phase. This is clearly explained at: Video "Quantum Mechanics 9b - Photon Spin and Schrodinger's Cat II by ViaScience (2013)".