# 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 symmetry to Euclid's axioms, and from binary numbers to the prosecutor's fallacy, learn some maths without too much effort.

Non-linear relationships are tricky relationships. Find out why here.

The concept of homotopy is a great example of how the language of maths can make intuition precise.

How would you explain the natural numbers to an alien devoid of a number instinct? You could try Peano arithmetic...

Tea gone cold? Don't worry, you can cheer yourself up with the theory of thermodynamics.

How does your phone know what the weather's going to be like?

Wet cats don't cause umbrellas and umbrellas don't cause wet cats.

If you've ever marvelled at a rainbow, you have witnessed dispersion in action!

Whether you want to understand viruses, win at lotto or solve a rubik's cube – you'll need some help from combinatorics.

A hundred pounds is a lot more to someone who's poor than to a millionaire. But how do you measure such differences? Utility theory has the answer.

Find out about the beautifully intuitive concept that lies at the heart of calculus.