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TIL the Hairy Ball theorem (wikipedia.org)

submitted 3 days ago* (last edited 2 days ago) by [email protected] to c/[email protected]

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The theorem has been expressed colloquially as "you can't comb a hairy ball flat without creating a cowlick" or "you can't comb the hair on a coconut".

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[–] [email protected] 4 points 1 day ago

I remember first hearing about the Hairy Ball Theorum when watching some of the extended features on our Monster's Inc DVD. One of the animators was talking about how they had to constantly be re-combing Sully's hair to make sure the cowlick was in an unseen location

I'll have to poke around at some point because there was a really neat video on that DVD as well that was talking about the origin of the Monsters Inc universe, and how the monsters both discovered the power of screams and built the doors/portals for reaching the human world and I remember it being super interesting and extremely fleshed out for something that literally never happen on screen and probably doesn't influence anything on-screen at all