Support me on Patreon and I will post you a free torus balloon. I hope I don’t regret this. https://www.patreon.com/standupmaths
Here is Sam Hartburn’s geogebra file: https://www.geogebra.org/m/yjtjxr2n
Thanks to Visual Topology & Geometry for “Punctured torus homeomorphism”. https://www.youtube.com/watch?v=tz3QW…
Me cutting two joined cylinders in half way back in 2015. Good times. (At 29:29.) https://youtu.be/1wAaI_6b9JE?t=1769
– When talking about the Euler Characteristic of the torus at 16:29 I say the value of zero is “only on our friend the torus” which is technically wrong. In the moment I was just talking about the sphere and the torus but loads of other shapes have an Euler Characteristic of zero. Like the cylinder.
– I’m undecided if the string method of thinking about holes at 17:04 was helpful. I could have talked about the dimension of the boundary manifold, but that felt like I was repeating the previous bit too much and wanted a different way to think about it. Not sure if this counts as a ‘correction’ per se, but I just needed to talk to someone about it. Thanks for listening.
– Let me know if you spot any other mistakes!
Filming and trouser sewing by Alex Genn-Bash
Editing by Michelle Martin
Graphics by Sam Hartburn
Doughnuts later eaten by Matt Parker
Music by Howard Carter
Design by Simon Wright and Adam Robinson
MATT PARKER: Stand-up Mathematician
US book: https://www.penguinrandomhouse.com/bo…
UK book: https://mathsgear.co.uk/products/5b9f…
Nerdy maths toys: http://mathsgear.co.uk/