Books on TilingEdit
One of the motifs in Anathem is tilings, particularly the aperiodic tilings that are used in the Teglon. Stephenson gives explicit credit to Roger Penrose, the inventor of the aperiodic Penrose Tilings. Here are some useful links if you want to learn more about these and other tilings.
Penrose, Roger, The Emperor's New Mind, Oxford University Press, 1989, ISBN 0-19-851973-7.
Penrose gives a thorough explanation of his aperiodic tilings in this book, but also touches on many other fascinating topics, including the nature of the human mind and whether its functions can be fully explained by a purely mechanistic, determinist model a la Hofstadter; or whether something else, possibly quantum mechanical in nature, is going on.
Grunbaum, Branko, and Shephard, G.C, Tilings and Patterns. W.H. Freeman and and Company, 1987, ISBN 0-7167-1193-1.
This book is the ultimate guide to all things tiling. It is mathematical, encyclopedic, but very readable.