This week and last I hosted a series of public maths talks featuring disabled presenters. I’ll post about how that went later, but for now I just want to share this clip of me filling time spreading Christmas joy.
This is a party trick that Katie Steckles showed me: you can fold a piece of paper and then make a single cut to produce a five-pointed star. I showed how to do it by following the instructions I’d been told, and then recreated the steps just starting from the insight that when you make the cut, all the edges of the shape need to be on top of each other.
Maybe you’ll show someone else how to do it during the Christmas holiday?
This doesn’t only work for stars: there’s a theorem that you can make any polygon by folding and a single cut. Erik Demaine has made a really good page about the theorem, with some examples to print out and links to research papers. Katie can cut out any letter of the alphabet on demand, which is impressive to witness!
It’s been a while since we’ve seen a MathsJam recap, but having restarted the MathsJam in Leuven after a hiatus, Dieter was too excited not to share what they’d been up to.
The first (re)edition of the Maths Jam in Leuven (Historic university city in Belgium) was a tiny success. I brought a couple of physical copies of the single page worksheet called the MathsJam Meta Shout with $\sim$10 problems from different sub areas of maths which I received earlier from Katie who coordinates MathsJams internationally.
The problems on the sheet were ranging from simple (?) Fold-and-cut fun, Tangrams (geometry), to some number theory, a touch of Linear Algebra and an easy arithmetic problem, solvable with 12-yo-level calculations (i.e. arrange all numbers from 1-15 so that each adjacent numbers sum to a square of a whole number under 16). Nice to see how broad the difficulty space is on the worksheet. Creative problem solving for (nearly) all ages!
On the second to last Tuesday of February 2022 (and hopefully each month from now), we were 3 in total. Which is a good number, I guess, for the Leuven revival anno 2022. Plenty of room to go from there – and a prime number, naturally! :-) Unfortunately we got kicked out of the venue at 21h30 (we started at 20h GMT+1) because we were the only ones left and the venue closes at 22h on Tuesdays (something I didn’t check, nor expected really). But puzzle minded we were, we just overflowed to someone’s home -after a rainy bike intermezzo which refreshened our minds. This didn’t stop us continuing our puzzling until 23h.
One of the attendees (a mathematician by degree) aced all the problems in <3h all the while (attempting) to explain his rationale. It was quite impressive to see! And fun too, because I definitely learned quite some things that night. I was still attempting to fold-and-cut the necessary T-shape with the proper dimensions (3 unit squares on top & 4 from top to bottom) when others had already finished their second tangrams (with some clever area proportion estimates). I forgot to bring my edition of the Set game so we didn’t participate in the online inter-MathsJam set-hunt – being only three we were too eager to just dive into the puzzles first.
After that second to last Tuesday, I tried some of the puzzles I hadn’t completed that night myself and I still haven’t finished them all just yet. (Some of them really make the gears in my brain grind!) I really liked the mix of complexity and variation in type of problems (kudos/thx/merci to all those involved in the making of the Shout).
New Leuven MathsJam venue, at Opek
I’m already eagerly looking forward to the next edition Shout and the next physical meetup by extension (Tuesday 22th of March), and have arranged a new venue for this month in the bar Café Entrepot of the local art center Opek. This seems very fitting for the subtle art of maths and I’ve got the guarantee that they will host us at length, yay! I sure hope to see you there on a second to last Tuesday soon. :-)
