Delphi.science

The Euclidean plane is not five-colorable

Source: github.com/openai/math/tree/main/preprints/The-Euclidean-pl…

OpenAI

OpenAI Mathopenai-math/The-Euclidean-plane-is-not-five-colorableSep 23, 2026math.COAI-generatedscore 0 · 🔥 3 posts

We prove that every coloring of the Euclidean plane with five colors has a monochromatic unit-distance pair, with no regularity assumption on the color classes. Consequently, the chromatic number of the plane is either six or seven.

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Conjectures that I thought would not be proved in my lifetime....wereblog.computationalcomplexity.orgBill Gasarch

For nearly 70 years, all that was known was \( 4\le \chi\le 7\). We denote \(\chi(G)\) by \(\chi\). The proof that \(4 \le\chi\) is easy. The proof that \(\chi\le 7\) is easy. In 2018, Aubrey de Grey improved the lower bound to 5 . The proof that \(5\le \chi\) is hard: it involves a 1,581-vertex…

Updates: Sharing AI progress on mathematics (amazing!); and my lecture plansCombinatorics and moreGil KalaiOct 7, 2026

raises the lower bound to six, leaving six and seven as the two possible answers. The Kakeya problem. My post on Hong Wang and Joshua Zahl’s breakthrough discussed the three-dimensional Kakeya set conjecture and the stronger maximal-function problem. The release announces the maximal conjecture in…

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