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As COP28, the 2023 United Nations Climate Change Conference, kicks off we look at how maths can help understand the climate crisis.

How do you create dramatic film out of mathematics? We find out with writer and director Timothy Lanzone.

Mathematics plays a central role in understanding how infectious diseases spread. This collection of articles looks at some basic concepts in epidemiology to help you understand this fascinating and important field, and set you up for further study.

Find out why the formula we use to work out conditional probabilities is true!

- We talk about a play that explores the fascinating mathematical collaboration between the mathematicians GH Hardy and Srinivasa Ramanujan.

I understand how these models can work for most traditional diseases, where infected individuals are no longer contagious after some period, and are generally immune, themselves. However, for a condition such as AIDS, where infected individuals are permanently infected (and without intervention, permanently contagious), what happens to the "gI" term in the equation for dI/dt (R being nonexistent).

If one were modelling HIV/AIDS, would they want to do something different with g?

Furthermore, in the equation for dS/dt, if beta is multiplied by S and I, shouldn't B be multiplied by the total population, and dS be multiplied by S?

Any clarification would be much appreciated. Thanks.