The Hairy Ball Theorem via Sperner's Lemma
نویسندگان
چکیده
It is impossible to comb all the hairs of a fuzzy ball so that: i) each hair lies tangent to the surface of the ball, and ii) the angles of the hairs vary continuously over the surface of the ball. (By this we mean that the angle between two hairs at positions p and q say can be made arbitrarily small by choosing q sufficiently close to p.) Any attempt to accomplish this feat must produce a cowlick.
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ورودعنوان ژورنال:
- The American Mathematical Monthly
دوره 111 شماره
صفحات -
تاریخ انتشار 2004