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Video of a sphere turning inside out without creasing

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The Geometry Center(Click image or here for video) Mathematicians are awesome. Don't believe me? Check out this 1994 animation, Outside In (I'd never seen it), which shows how to "evert" a sphere, or turn it inside out without tearing, pinching or creasing it. Letting it pass through itself is allowed. Click here for a history of sphere eversions and their visualizations, in which you'll discover that the Outside In method is actually more elaborate than necessary. (Gratuitous plug: The cover of the October 1993 SciAm depicted a step in the eversion process.) via John Baez by way of Scott Aaronson