Largest hyperbolic crochet

Parallel lines remain parallel forever – at least, they do according to the ancient Greek philosopher Euclid, who first formulated the laws of mathematical geometry. Later, however, mathematicians realised that Euclid’s laws, or "axioms", only apply in flat space. On the spherically curved surface of the Earth, for example, lines of longitude start out parallel at the equator but cross over at the poles. A sphere is said to have positive curvature but there are negatively curved spaces too, in which lines start out parallel but then diverge – these are known as "hyperbolic" spaces and resemble a kind of saddle shape. Latvian mathematician Daina Taimina has come up with a novel way of illustrating hyperbolic space – by crocheting it. Her largest hyperbolic crochet measures 70 x 70 x 50 cm, weighs 6.3 kg and is woven from a staggering 7.8 km of yarn.