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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.

The Grandi Series (1-1+1-1+1 . . .) was actually proved as follows:

Z=1-1+1-1+1 . . .

1-Z=1-(1-1+1-1+1 . . .)

1-Z=1-1+1-1+1-1 . . .

1-Z=Z => 2Z=1 => Z=1/2

This is perfectly true and can be used without controversy in the remaining half of the proof. Adding Z to both sides would work as an alternative proof, but it would have to be done as follows:

Z=1-1+1-1+1 . . .

Z+Z=1-1+1-1+1 . . .

+1-1+1-1 . . .

After which everything cancels out, except the 1:

2Z=1 => Z=1/2.

The way that was shown in the article wouldn't work because there is no way to know whether the second Grandi Series is being started at +1 or -1 in the original Grandi Series.