It was one year ago today that David Smith emailed me out of the blue, asking about my work on computing Heesch numbers. A few days later he tipped his hand and showed me a drawing of the hat polykite for the first time. Happy Aperiodic Monotile day to all who celebrate.
@csk for anyone wanting a physical representation to play with: https://www.printables.com/model/430171-einstein-hat-worlds-first-aperiodic-monotile
And for the upcoming birthday: https://www.printables.com/model/494205-einstein-spectre-worlds-first-chiral-aperiodic-mon
