Peter Markowich is a mathematician who likes to take pictures. At first his two interests seemed completely separate to him, but then he realised that behind every picture there is a mathematical story to tell. Plus went to see him to find out more, and ended up with a pictorial introduction to partial differential equations.

How to keep inflation down

This issue's teacher package brings together all Plus articles on group theory, exploring its applications and recent breakthroughs, and giving explicit definitions and examples of groups. It also has some handy links to related problems on our sister site NRICH.

Perpendicula, the magnificent princess of the rectangle, is admiring her magnificent new bathroom. It's rectangular of course; 10m wide and 20m long. It still needs tiling, though, and Perpendicula has ordered tiles of pure gold to mirror the dimensions of the bathroom: they are 1m wide and 2m long.

Loquacious maths

Food evolution

Modelling Olympic success

Modelling terrorist activity

Will we