BBC Radio 4 put out a rather nice 30-minute documentary on the links between maths and magic recently. In Maths and Magic, Jolyon Jenkins explains a couple of simple algebraic ‘mind-reading’ tricks, before talking to various magicians and mathematicians in search of a mathematical trick that doesn’t ‘look’ mathematical. Regular readers of this site will recognise a few of the mathematicians featured in the programme.
I’m now a bit miffed that I managed to miss Jolyon at the big MathsJam in November, because the trick he ends with is the easy version of the de Bruijn trick that David and I made better last year.
Listen: Maths and Magic on BBC Radio 4.
Readers of The Aperiodical may recall three excellent posts on the Maths of Star Trek by Jim ‘But Not As We Know It’ Grime. At the same time, Jim discussed the topic in glorious audio with Andy Holding and Will Thompson, hosts of the Science of Fiction podcast (worth listening to, but at least visit the page to see a picture of Jim nursing a tribble). As part of this, the hosts asked Jim what uniform colour mathematicians on the Enterprise would wear.
JIM: Science and medics, those are the blue shirts.
HOST: Where do mathematicians go? Scientists?
JIM: That’s right, yes, science.
HOST: You’re safe?
JIM: Yes, I am, I’m in the blue shirt category.
Jim is pleased to say that mathematicians wear blue because, as he explains, gold and red uniformed crew were much more likely to be killed during the famous five-year mission than those in blue. I’ve written in the past about maths and mathematicians being everywhere, for example when asserting that most of the Nobel prizes are for mathematics. Was Jim right about those blue-shirted mathematicians?
You may have seen an article linked to last week, written by Jordan Weissmann at The Atlantic. The article was titled ‘Here’s How Little Math Americans Actually Use At Work‘, although mysteriously this journalist makes use of some mathematical analysis of survey data, and not only that, the data appears to show that 94% of Americans claim to use mathematics as part of their daily job.
The article discusses people’s misconceptions about the future utility of what they were learning, as well as the divide between using ‘any math’ and ‘advanced math’, which includes calculus, algebra and statistics. The number of Americans who admitted to using this type of maths appears to drop off once you get to anything more complicated than fractions, and also presented is an analysis of this divide by job type.
A very well-written and thoughtful response to this has already been posted at mathematics professor Bret Benesh’s blog, which gives four reasons why the article annoyed him (and probably several other people too).
Numberphile filmmaker and general internet legend Brady Haran has been busy putting together a series of YouTube videos about the Rubik’s cube, with contributions from Aperiodical friends Matt Parker and James Grime. The videos also feature lots of solving clips sent in by viewers, and Aperiodical Editor triumvir and sometime maths-talker-abouter Katie Steckles (that’s me) occasionally pops in to make comments and state facts which are no longer true (a world record was broken 4 days after filming).
Anyone who hasn’t yet spotted the YouTube channel Numberphile (call yourself a maths fan?) would do well to check out its amazing selection of videos, all loosely themed around numbers – not all of which are integers, either – but now edging on giving up on that pretence and just continuing to post videos about interesting bits of maths.
James Grime has come out in support of the campaign to put Alan Turing on the £10 note. He explains about this in a new video.
The “Futurama theorem”, also known as Keeler’s Theorem after its creator, was a bit of maths invented for the Futurama episode The Prisoner of Benda, to solve a problem where the characters get their heads mixed up and need to swap them back without any one pair swapping heads twice. It was enthusiastically reported by the geeky press, and rightly so, because it’s a fun bit of real maths with a wonderful application. Dana Ernst has written some very good slides about the theorem, working from “what is a permutation?” up to the algorithm itself.
Anyway, some students from the University of California, San Diego have extended the result, giving a better algorithm for finding the minimum number of switches to put everyone’s head back in the right places, give optimal solutions for two particular situations, and give necessary and sufficient conditions for it being possible to represent the identity permutation as $m$ distinct transpositions in $S_n$.
via James Grime