## Articles

**Jerry Gollub**tells

*Plus*about a new discovery which combines experiment with sophisticated maths.

**Carola Schönlieb**explores how mathematicians use the heat equation to fill in the gaps.

**David Spiegelhalter** and **Mike Pearson** explore how risk can be spun and there's an interactive animation for you to have a go yourself.

*A disappearing number*, a work by Complicite, inspired by the mathematical collaboration of Hardy and Ramanujan.

**Rachel Thomas**went to see the play, and explains some of the maths. You can also read her interview with Victoria Gould about how the show was created.

**Phil Wilson**looks at

*constructivist mathematics*, which holds that some things are neither true, nor false, nor anything in between.

**Angus Brown**looks at one of these, a simple model for option pricing, and explains how it takes us on the road to the famous Black-Scholes equation of financial mathematics, which won its discoverers the 1997 Nobel Prize in Economics.

**Colva Roney-Dougal**explores the maths, from chaos to group theory.

**John Billingham**investigates and saves the national grid in the process.