### Crochet Math

A few months ago, we were fortunate enough to have a display of crochet art by Daina Taimina in the lobby of the American Center for Physics. The pieces sat in glass cases surrounding our rotunda. When I first saw them I had no idea what they were supposed to be, although some reminded me of the wood ear fungus on trees just outside the building. In fact, they were crochet examples of hyperbolic planes.

I confess that the whole idea of hyperbolic planes is a bit beyond me (the wikipedia page didn't help much, although now I know the word hyperparallel), even though the artist herself explained it to us at the art opening. But looking at Taimina's pieces certainly gave me an intuitive feel for the math. I only wish we had been allowed to pass them around to touch them and stretch them out a little.

I guess I'll have to make my own hyperbolic plane crochet toy to play with. Fortunately, the instructions are available in the book Taimina wrote with David Henderson. It's on the shelf at the University of Maryland library just down the road. Of course, first I'll have to learn how to crochet.

Those of you who already have mad crochet skills may understand this simple instruction on The Institute for Figuring page that shows lots of examples. "Taimina intuited that the essence of this construction could be implemented with knitting or crochet simply by increasing the number of stitches in each row. As you increase, the surface naturally begins to ruffle and crenellate." Increasing the count in subsequent rows by different numbers gives different shapes, apparently.

Check out the rest of Taimina's designs in her online gallery.

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