My maths object this time is one of my dog’s favourite toys: the Nobbly Wobbly.
In the video, I said it was invented by a mathematician, but Dick Esterle’s bio normally goes “artist, architect, inventor”. I’ll leave it up to you to decide if Everyone’s a Mathematician.
It’s a particularly pleasing rubbery ball thing made of six interwoven loops in different colours, invented by Dick Esterle.
On Google+, various people told me the unexpected fact that the outer automorphism group of $S_6$ is hiding inside this dog toy.
I’ve also found this Celebration of Mind livestream starring Dick Esterle from 2013 talking about all sorts of mathematically-shaped toys, including the Nobbly Wobbly.
Here’s another one of my favourite maths objects: the Correntator. It’s a simple mechanical tool to add up amounts of money. I bought it for about a tenner (new money) at a market.
This video is extremely shonky. Blame my phone, which can’t bring itself to record for more than 250 seconds at a time.
More information about the Correntator.
Time for some more maths objects! This time I wanted to show you the various polyhedra I’ve got around my desk.
I had the idea of doing short videos about mathematical objects I’ve got lying around. First up is a very unconventional group theory textbook.