Wikipedia @lemmy.world LeftRedditOnJul1 @lemmy.world 1年前 Hairy Ball Theorem en.m.wikipedia.org Hairy ball theorem - Wikipedia 1 转贴 Tan Eggs @lemmy.ca Evil_Shrubbery @lemm.ee 6个月前 You can't comb a tan egg flat without creating a cowlick en.m.wikipedia.org /wiki/Hairy_ball_theorem