## Articles

**Mike Yates**looks at the life and work of wartime code-breaker Alan Turing. Find out what types of numbers we

*can't*count and why there are limits on what can be achieved with Turing machines.

**Julian Stander**tells us about the increasing role of statistics in interpreting them.

**Geoffrey Grimmett**explains how probability is at the heart of it all.

**David Henwood**discusses the vibrations that can be harnessed by musical instrument makers.

**David Henwood**explains the role of mathematics in the design of Hi-Fi loudspeakers.

We know there is infinitely many primes, but are there infinitely many twin primes?