Categories: On the Beauty of Physics is a non-fiction science and art book edited, co-written, and published by American author Hilary Thayer Hamann in 2006. The book was conceived as a multidisciplinary educational tool that uses art and literature to broaden the reader's understanding of challenging material. Alan Lightman, author of Einstein's Dreams, called Categories "A beautiful synthesis of science and art, pleasing to the mind and to the eye," and Dr. Helen Caldicott, founder and president of the Nuclear Policy Research Institute, said, "This wonderful book will provoke thought in lovers of science and art alike, and with knowledge comes the inspiration to preserve the beauty of life on Earth."