Are there "elementary" resources on [Penrose Tilings][1] in relation to [noncommutative geometry][2]? It's all a big blur to me. There are two transformations S and T that can grow the tilings and every tiling corresponds to a sequence of S's and T's. Somehow, there is a C* algebra related to this. Can the elements of this algebra be interpreted as observables in a quantum mechanical system? What is the "geometry" of this noncommutative space? ![Penrose Tiling][3][(source)][4] [1]: http://en.wikipedia.org/wiki/Penrose_tiling [2]: http://www.alainconnes.org/docs/book94bigpdf.pdf [3]: https://i.sstatic.net/7IMz0.png [4]: http://www.jdawiseman.com/papers/trivia/penrose_tiling.png