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.

Maths in a minute: Einstein's general theory of relativity

What would happen if the Sun suddenly exploded? Einstein wondered the same thing, and completely changed our understanding of the Universe.

Maths in a minute: Symmetry

We all instinctively recognise symmetry when we see it, but describing it in words is harder than you might think.

Maths in a minute: The second law of thermodynamics

Our messy desk is proof of the second law of thermodynamics...

Maths in a minute: Simplifying circuits

Claude Shannon's ingenious insight linking physical circuits with Boolean algebra paved the way for modern computing.

Maths in a minute: The central limit theorem

Opinion polls, election forecasts, testing new medical drugs — none of these would be possible without the central limit theorem.

Maths in a minute: Bayes' theorem

It would be foolish to ignore evidence. Luckily Bayes' theorem shows us how to take it in into account.

Physics in a minute: What's the problem with quantum gravity?

At the heart of modern physics lurks a terrible puzzle: the two main theories that describe the world we live in just won't fit together.