Coral reefs can be crocheted. The atmosphere can be knit. And a stop sign can be folded into a pair of pants. Subscribe to read this story ad-free Get unlimited access to ad-free articles and ...

On a Thursday night in Ithaca, New York, Daina Taimina, an ebullient blond mathematician at Cornell University, sits at her kitchen table with her husband, David Henderson, a Cornell professor of ...

Jean Zeller, Wendy Ellis and Janet Allen, from left, demonstrate the hyperbolic crochet technique that was used by members of the Lancaster Yarn Shop's Thursday Night Knitting Group to create pieces ...

This is a hyperbolic pseudosphere—made with nothing more than yarn and a crochet hook. Hyperbolic geometry describes surfaces that are negatively curved. If you're enjoying this article, consider ...

Using yarn and two pointy needles (knitting) or one narrow hook (crochet), pretty much anyone can stitch up a piece of fabric. Or, you can take the whole yarncraft thing light-years further to ...