Apparently all the covid virus in the world could fit into a soft drinks can with space to spare. The calculation is set out in a piece by the mathematician Christian Yates in an article for The Conversation. The question was originally posed by my favourite Radio 4 programme, More or Less, and it got me thinking about a similar question the programme asked a few years ago.

In 2011 it set out to test the notion that the whole of the world’s population could fit on the Isle of Wight. The experiment in those distant pre-covid days involved squeezing Radio 4 staff into a 4m² studio and then scaling up. The answer was that it was just possible but would be a bit of a squeeze.

The American urbanist Edward Glaeser did something similar in his book Triumph of the City, calculating that all of humanity could live in Texas, except in this case we would all have our own personal townhouse. Texas is huge, of course, so in my lectures I translate this for a UK audience by suggesting the world’s population could live in a city the density of Paris and the size of Yorkshire.

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