## navier-stokes equations

An insightful look at the climate models that predict our future.

The mathematical problem with turbulence.

Few things in nature are as dramatic, and potentially dangerous, as ocean waves. The impact they have on our daily lives extends from shipping to the role they play in driving the global climate. From a theoretical viewpoint water waves pose rich challenges: solutions to the equations that describe fluid motion are elusive, and whether they even exist in the most general case is one of the hardest unanswered questions in mathematics.

Africa isn't a continent that's famous for cutting edge research. But at the University of Stellenbosch, 50km East of Cape Town, South Africa, Kiran Dellimore and his team are engineering medical equipment that will save the lives of people all over the world. Latest projects include replacement heart valves made from kangaroo tissue and equipment to help resuscitate people in emergencies.

**Ben Evans**explains how maths is used to build this car.

**Andy Green**, Royal Air force pilot and Oxford maths graduate, is gearing up to break his own land speed record in Bloodhound SSC, a supersonic car designed to reach speeds of up to 1000mph. He tells

*Plus*about the challenges — and the maths — behind this engineering adventure.

**Jerry Gollub**tells

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

**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.

**Phil Trinh**discovers how maths helps solve the mysteries of flight and love.