A counterexample to periodic tiling in dimension three

Formal proof listed 1 paper September 23, 2026
What the paper claims, in its own words

Constructs a finite translational tile in ℤ3 that tiles space but admits no fully periodic tiling, disproving the periodic tiling conjecture in the smallest possible lattice dimension. Its unit-cube thickening gives the same counterexample in ℝ3, even with arbitrary real translation vectors.

The plain-language explainer for this entry is still coming.

The original paper