
A couple of words about the background. This is one possible solution to the shapes and rules set forth by Sir Arthur Penrose (and copyrighted by him, too.

In college, I had a class with a brilliant woman, Marjorie Senechal. She taught us discrete mathematics, and a class on tilings, both of which were thoroughly enjoyable classes. In addition, she looked strikingly like the white queen from Tenniel's illustrations for Through the Looking Glass.
Professor Senechal is a world expert on quasicrystals, and predicting semi-regular tilings. She wrote the book, which sits admired and misunderstood on my shelf, Quasicrystals and Geometry.
Quasicrystals are described as "periodic in a higher dimension," which I find pretty trippy stuff. What does this have to do with Penrose tiles? Well, apparently, if you bisect each side of the tiles, and connect the ones that are parrallel and share a tile,

Penrose tiles are a rich symbol for me of all of the mathematics I studied, and loved, even when I wasn't always very good at it, or didn't understand it. I left it all behind when I started studying art more seriously. Maybe I will go back and get a phD in math when I'm an old woman...
I remember sitting on this bench in Amsterdam, covered with Penrose tiles! (photo by Javier Lopez.)
