The hat polykite is an aperiodic monotile discovered by Smith et al. (2023).
It is illustrated above in an aperiodic tiling (Smith et al. 2023).
Hat Polykite
See also
Aperiodic Monotile, Aperiodic Tiling, Kite, PolykiteExplore with Wolfram|Alpha
References
Pegg, E. "Einstein Problem Solved (Aperiodic Monotile Discovery." Mar 21, 2023. https://community.wolfram.com/groups/-/m/t/2856178.Smith, D.; Myers, J. S.; Kaplan, C. S.; and Goodman-Strauss, C. "An Aperiodic Monotile." 20 Mar 2023. https://arxiv.org/abs/2303.10798.Cite this as:
Weisstein, Eric W. "Hat Polykite." From MathWorld--A Wolfram Web Resource. https://mathworld.wolfram.com/HatPolykite.html