Hacker News new | ask | show | jobs
by IAmBroom 303 days ago
It's not. It's about closed surfaces, which include the surface of spheres, oblate spheres, footballs, pencils, and airplanes.
1 comments

Well, all these closed surfaces you mention are (topologically) spheres. The theorem doesn’t apply to some other closed surfaces, like the torus, which does admit a continuous non-vanishing vector field.