# Tennis ball theorem

> smooth curve that divides a sphere into 2 equal-area subsets has at least 4 inflections

**Wikidata**: [Q55634934](https://www.wikidata.org/wiki/Q55634934)  
**Wikipedia**: [English](https://en.wikipedia.org/wiki/Tennis_ball_theorem)  
**Source**: https://4ort.xyz/entity/tennis-ball-theorem