Document Type

Conference Proceeding

Publication Date


Publication Title

Proceedings of the 18th Annual Canadian Conference on Computational Geometry, CCCG 2006


Every simple planar polygon can undergo only a finite number of pocket flips before becoming convex. Since Erdős posed this as an open problem in 1935, several independent purported proofs have been published. However, we uncover a plethora of errors and gaps in these arguments, and remedy these problems with a new (correct) proof.

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