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James Grime answers your Shakuntala Devi questions

This is a follow-up to James’s FAQ for the 2014 film The Imitation Game.

Shakuntala Devi is a 2020 Indian Hindi-language film about Shakuntala Devi, a performer of impressive mental calculations, available now on Amazon Prime.

The extraordinary Cardano family

In this guest post by David Benjamin, we explore a little of the life and times of Girolamo Cardano and his interesting family.

Girolamo Cardano (1501- 1576) was at various times in his life a physician, mathematician, inventor, addictive gambler and prisoner. He was the illegitimate son of Fazio Cardano and Chiara Micheria, and the Cardano family was a dysfunctional 16th Century version of the Simpsons.

Doughnuts in the Sand

This is a guest post by semi-regular guest author, mathematician-turned-maths-teacher Andrew Stacey.

I like having something mathematical to think about for times when I’m, for example, waiting in a queue to get into the supermarket. Annie Perkin’s Math Art Challenge has been a good source of such of late. These are a series of mathematically-inspired artistic activities, ranging from designing celtic knots to constructing origami polyhedra and everything in between.

My eye was caught by one on sandpiles – I’ll explain exactly what they are in a moment. One feature that made it attractive was that it was quite simple to write a program to generate diagrams. I find that the maths that interests me usually comes from looking at variations, and for that I need to generate a lot of examples. Doing them by hand quickly becomes laborious. So I whipped up a program (which I later converted to an online version) and ran it a few times to see what happened.


Andrew Stacey: I have a confession to make that would probably get me thrown out of every respectable Mathematics Society – were I to belong to one.

I am not a fan of the Fibonacci sequence.

Neither am I keen on the golden ratio. It’s not even transcendental.

It’s not really their fault, it’s just that they get levered in everywhere whether they belong there or not. Particularly in discussions of nature and beauty, and this is exemplified by that ridiculous origin story. We’ve been subjected to a variety of bizarre origin stories over the years (cough radioactive spider cough) but the rabbit story is another level of bizarre.

So I was intrigued, and then delighted, when one of my students, who is a bee enthusiast, told me about a genuinely natural occurrence of the Fibonacci sequence in the ancestry of bees.

I’ll let her take up the story.

Coding Stories: Programming Polygons

In this guest post, Greg Benedis-Grab shares the story of when he discovered Pick’s Theorem, and how he coded an interactive version to play with.

Have you ever been intoxicated by a mathematical theorem? Well that’s what happened to a class of 9th grade geometry students at my school. Their enthusiastic teacher showed them Pick’s theorem.

Conway’s Circle Theorem: a proof, this time with words

Back in the olden days, Colin entered a proof without words in the Big Mathoff. It was mentioned, in passing, in a New York Times obituary of John Horton Conway.