## University of Cambridge

In the 1920s the Austrian physicist Erwin Schrödinger came up with what has become the central equation of quantum mechanics. It tells you all there is to know about a quantum physical system and it also predicts famous quantum weirdnesses such as superposition and quantum entanglement. In this, the first article of a three-part series, we introduce Schrödinger's equation and put it in its historical context.

John Barrow gives us an overview, from Aristotle's ideas to Cantor's never-ending tower of mathematical infinities, and from shock waves to black holes.

This is an excerpt from Stephen Hawking's address to his 70th birthday symposium which took place on 8th January 2011 in Cambridge.

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

Well, no-one knows exactly, but using stats you can make a good guess. This article tells you how and has an interactive life expectancy calculator. Do you dare to find out?

**Jim Woodhouse**and

**Paul Galluzzo**explain why.