Spontaneous knotting of an agitated string

@article{Raymer2007SpontaneousKO,
  title={Spontaneous knotting of an agitated string},
  author={Dorian M. Raymer and Douglas E. Smith},
  journal={Proceedings of the National Academy of Sciences},
  year={2007},
  volume={104},
  pages={16432 - 16437}
}
It is well known that a jostled string tends to become knotted; yet the factors governing the “spontaneous” formation of various knots are unclear. We performed experiments in which a string was tumbled inside a box and found that complex knots often form within seconds. We used mathematical knot theory to analyze the knots. Above a critical string length, the probability P of knotting at first increased sharply with length but then saturated below 100%. This behavior differs from that of… 

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