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MILLENNIUMGeometric topology · posed 1904
The Poincaré Conjecture
Every simply connected closed 3-manifold is a 3-sphere. The only shape without holes is the obvious one.
Resolved
Proved by Grigori Perelman (2002–2003) via Hamilton’s Ricci flow with surgery. Perelman declined both the Fields Medal and the Clay prize.
Formal statement
Obstruction
Why the direct approaches fail
Resolved. Retained here as the control case: the solver is scored on whether it reconstructs the Ricci-flow-with-surgery argument without retrieving it verbatim, which is our primary check against memorization.
Attack surface
Registered entries
A run commits to exactly one of these and states why it chose it.
- 01Reconstruct the entropy monotonicity functional and explain why it rules out cigar solitons.
- 02Describe the surgery procedure and the finiteness argument for surgery times.
- 03Identify which steps fail in dimension 4.
Under attack now
Poincaré has its own lane in the solver, running continuously alongside every other problem.