1023 Multiplication

The exponential growth of coronavirus can be explained 

by rice on a chessboard. And we should be worried.

It's the maths.


There's a mathematical law driving the growth in the number of coronavirus cases globally, which makes health experts so fearful.


The human brain wasn't built to think naturally about complicated mathematical phenomena. It's fine with basic maths, like simple percentages. But the brain can turn to mush when faced with more complicated problems, if it hasn't been taught how to think them through.


A famous example is the rice and chessboard problem.


If someone gave you a chessboard (which has 64 squares on it) and asked you to put one grain of rice on the first square, two grains of rice on the second square, four grains of rice on the third, eight grains on the fourth, and so on, how many grains of rice would end up on the 64th square?


It sounds like an easy question - it's simply asking you to double the number of rice grains from one square to the next, from 1 grain to 2 to 4 to 8 to 16 to 32 to 64, and so on, until the 64th square.

Well, I’m glad someone has done the precise maths, I couldn’t do it when I wrote - years ago - my essay  MULTIPLICATION ... it was doing my head in.


What's the answer? You'd need 9,223,372,036,854,775,808 grains of rice for the 64th square.


That's nine quintillion, two hundred and twenty three quadrillion, three hundred and seventy two trillion, thirty six billion, eight hundred and fifty four million, seven hundred and seventy five thousand, eight hundred and eight grains.


And the amount of rice you'd need to cover the entire board - from squares 1 to 64 - would be 18.4 quintillion grains.


That's 923 times the entire estimated global production of rice this financial year.


Anyway, back to C-19 (do read the article at ABC News), the answer to my original question: " What would happen if the number of C-19 deaths were to double every week?" is that once we counted across just over half the chessboard - 35 weeks -  the entire world population of approx. 7.5 billion would have been wiped out. So there.