In Part 3 Julia refines our model to use one of the most important numbers in disease modelling. And there's a chance for you to explore its meaning using a new interactivity.

In the final Part we explore what other aspects we need to consider to make a model more realistic. There's an interactivity that allows you to party, commute, and visit friends and we find out more about what life as a research is like from Julia.

In this final part, you can meet the researchers themselves and find out about the real research questions that Julia and some of her colleagues are working on!

To work out how a disease will spread you need to know the time between infections.

How can we use mathematics to model the spread of a disease?

The doubling time of a disease is the time it takes for the number of cases of the disease to double. How do you calculate it?

What is the growth rate and what does it tell us about an epidemic?

News stories have claimed they may have — but is this true?

Can mathematics help reshape our hospital networks?

We discuss new and fascinating observations of gravitational waves with three of our favourite cosmologists.

In this special podcast we look back on this remarkable mathematical moment with Andrew Wiles, Jack Thorne and Tom Körner, and how it opened new doors onto the future of mathematics.

Andrew Wiles's proof of Fermat's Last Theorem solved a centuries-old problem by opening a door onto the future of mathematics.