two-sidedsurface

In the first of a new series 'Imaging Maths', Plus takes an illustrated tour of an extraordinary geometric construction: the Klein bottle.

Maths in a minute

Want facts and want them fast? Our Maths in a minute series explores key mathematical concepts in just a few words.

From an ecologist's nightmare to a mathematician's dream

Tracing the path of invading species using a famous problem in graph theory.
Maths in a minute: Transcendental numbers (and politics)

A quick introduction to transcendental numbers, a famous problem which relates to them, and how the person who solved it became a victim of political tensions.
Fantastic fractals

Escaping the tyranny of the straight line.
Packing spheres

How to arrange oranges in higher dimensions.
Blockchain: Spreading trust

Bitcoin is a digital currency that isn't regulated by any kind of central authority. The structure which allows this decentralisation is called blockchain. But how, and how well, does it work?