The Problems

Not schoolwork — the questions that resisted Erdős, Hilbert, and everyone since. The club keeps three shelves: what is still open, what AI recently settled, and what took humanity centuries.

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The Poincaré Conjecture historic

Is a simply-connected closed 3-manifold necessarily a sphere? Ninety-nine years, one recluse, and the only Millennium Prize ever claimed.

Posed by Henri Poincaré · 1904 · topology · resolved 2003 · difficulty 4/5

3-manifolds