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”.
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”.
For mathematicians in Germany, this is known as the “Hedgehog Theorem” (“Satz vom Igel”, as in “you can’t fully comb a hedgehog”)
I think it would be hard to find a hedgehog that would allow itself to be combed.