
In 2023, after decades of searching, mathematicians discovered a shape called āthe hatā ā so named for its passing resemblance to a fedora ā that can tile a 2D surface without gaps and without ever creating a repeating pattern. Now, a researcher has used AI to go one dimension better and discover a 3D shape that can do the same thing.
Simple shapes like squares can tile a 2D surface, but will form repeating patterns. So-called aperiodic tiles achieve the former without the latter ā you can scroll in any direction, infinitely, and not find a regularly repeating pattern.
That sounds like a nifty but ultimately useless mathematical curiosity, but since the 2023 publication of the 2D tile, it has been used in scientific papers in fields from engineering to chemistry. Some have explored the likely physical properties of a . Others have found that structures built using hat-shaped building blocks could be than those built using famously strong honeycomb-like building blocks.
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Now, , a software developer with no background in mathematics, has used AI to discover a 3D monotile he calls Chair44. He did so by describing the 2D problem to OpenAIās GPT-6 Astra modelĀ and asking it to find a similar result in three dimensions.
āAstra found this, I didnāt find the tile,ā says Tsiokos. āI gave Astra the theory, I gave it the laws, I gave it the theorems, the Lean code, the papers, and I said: āHereās the problem.ā Itās kind of cheeky: Iāve been in forums with other mathematicians, and [of] course theyāre all angry with me⦠because I donāt have the background to land this result.ā
Tsiokos says he also used AI to write the paper describing the finding, and has published around 40 papers in the same way, with another 20 that he is yet to release. But, as he suggests, not all mathematicians are impressed by the way the discovery has been disseminated.
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at the University of ArkansasĀ described the paper as ābasically a piece of slopā, and says that while the result is valid, the paper does little to clarify or explain it. āIncontrovertibly, thereās a very, very pretty result that emerges here,ā he says. Goodman-Strauss has since .
at the University of Bristol in the UK has also showing that Chair44 can be simplified and retain its aperiodicity.
at the University of Waterloo, Canada, was one of the researchers behind the 2D aperiodic tile. He says the new paper has āall the usual deficiencies of AI-generated mathematicsā in terms of readability and clarity, but that, despite this, the actual shape appears to be a valid solution.
āIt goes without saying that many of us have been contemplating the search for a 3D aperiodic monotile, and I can say that itās a natural question people ask when I give talks on the hat,ā says Kaplan. āBut I was always daunted by the simple prospect of visualising the problem or candidate solutions. Even if I had some shape that looked promising, how should I go about understanding large 3D assemblies of that shape?Ā Evidently, a computer doesnāt have to struggle as hard.ā
arXiv