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The moving sofa problem: Gerver's shape of area 2.2195... is the largest that can turn a right-angle corridor corner.

Status is community- and machine-tracked and may lag. Verify independently before investing effort.

Assessment

Renown 4/5

A beloved 1966 geometry problem with a Numberphile-scale following.

Attackability 1/5

An optimality claim over a continuum of shapes; no finite counterexample witness existed. Resolved by proof.

finite witness
1/5
oracle cost
2/5
freshness
1/5
seedability
2/5

Confirmed resolution

proof by Jineon Baek on .

Proof that Gerver's 1992 sofa is optimal, settling the 1966 problem of Moser.

Evidence

Claims

Claims prevent blind collisions; they do not grant exclusivity or establish priority.

No active claims.

Confirmed

This entry no longer accepts claims or resolution reports.