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Double Maths First Thing: Issue 46

By Colin Beveridge. Posted January 7, 2026

Double Maths First Thing is struggling with its J perms

Hello, and happy new year! My name is Colin and I am a mathematician on a mission to spread joy, delight and happiness in not-understanding and then, finally, understanding maths.

I’m getting back into a routine after a couple of weeks of childcare. That means writing, pulling apart weather spreadsheets and helping A-level students get on top of their studies. I’ve also got designs on dramatically improving my blindfold cube-solving, as well as doing it the more boring way, looking as I go.

There’s one last 2025 thing to ruin your next few days with: Thomas Colthurst’s 2025 game, which is like the Only Connect wall but with 45 groups of 45 items.

Important news for 2026 is that Doomsday is Saturday – the last day of February, Pi Day, July 4th, Hallowe’en and Boxing Day all fall on Saturday, as do 4/4, 6/6, 8/8, 10/10 and 12/12, 5/9 and 9/5, 11/7 and 7/11.

Links

Slightly after the deadline for last week’s DMFT, Peter Rowlett mentioned he’d been involved in a mathematically interesting Secret Santa. I can’t vouch for it because I haven’t watched it, but I gather it involved excellent people.

No Pseudorandom Ensemble show would be complete without an investigation into how many centres a triangle needs. Songwriter Sam Hartburn (who you should definitely hire if you need creative mathematics, editing or writing) investigates one of them (the nine-point circles) here. I think it’s one of the few that isn’t mentioned in the song.

I don’t play Pokémon, but there is apparently good maths involved. Nicolas Chagnet dives into how one could optimise teams.

Swerving slightly into coding, I enjoyed this piece from Christian Ekrem about some category theory jargon (functors, applicatives and monads) that I only ever get a hazy understanding of. Functors, I understand now. The others, I need to read the article again.

Via Sanjeev’s Carnival (of which more in a minute), a piece by Rodrigo Treviño in the Mathematical Intelligencer about negotiation and game theory.

Currently

The Bridges Maths and Art conference is in Galway this August – there’s a call for submissions in case you want to exhibit or present.

The latest Carnival of mathematics is up, courtesy of Sanjeev at the Scribble Board. You can submit links to the next edition from the Carnival page; it’ll be hosted by Laura at Letters and Words.

If you enjoy DMFT – and I hope you do – you’re likely to enjoy the Finite Group, as much for the cool chat in the Discord as for the monthly livestreams.

That’s all I’ve got for this week. If you have friends and/or colleagues who would enjoy Double Maths First Thing, do send them the link to sign up – they’ll be very welcome here.

If you’ve missed the previous issues of DMFT or – somehow – this one, you can find the archive courtesy of my dear friends at the Aperiodical.

Meanwhile, if there’s something I should know about, you can find me on Mathstodon as @icecolbeveridge, or at my personal website. You can also just reply to this email if there’s something you want to tell me.

Until next time,

C

Double Maths First Thing: Issue 2C

By Colin Beveridge. Posted July 9, 2025

Double Maths First Thing couldn’t possibly comment.

Hello! My name is Colin and I am a mathematician on a mission to spread joy and delight in engaging with maths, for any reason or for none. I’ve made it back from rehearsal and am feeling a lot better (thanks for asking).

(By the way, if you know of any Colin-shaped work, please let me know about it — I’d love something stable, remote, part-time and reasonably paid but neither soul-crushing nor burnout-inducing. Plus the moon on a stick, obviously. I can write. I can code. I can solve weird problems. There must be something, right?)

Links

Let’s start with something on my to-read list: Tai-Danae Bradley’s guide to category theory and notes on Applied category theory. I feel like there’s something going on a level up from where I normally look at things and that category theory might be a lens to examine it through.

A nice series of posts by Ioanna Georgiou and Asuka Young on mathematical themes implicit in the situation-comedy Friends, which I gather many cooler people than me are into.

We all know and love the rhombic dodecahedron, but Robin Houston is at pains to point out that it’s not the RD, but a RD..

David Eppstein has been to Kanazawa, Japan and found plenty of geometrical street art. Meanwhile, John Carlos Baez is in Athens, where the maths department is full of graffiti.

And following on from Minesweeper in issue 2B, we’ve now got Mark Round’s Primesweeper. Which is not in the slightest bit stressful.

Currently

I enjoyed the Finite Group livestream last week, especially the bit about bees’ ancestry following a Fibonacci sequence. You can join and, for a very reasonable monthly outlay, have access to some of the previous livestreams and all of the new ones. (You can even join for free and hang out in the Discord with awesome maths people.)

One small appeal from me: it’s striking, looking back through past DMFTs how heavily the links skew towards male (or male-presenting) mathematicians. I’m keen to amplify the voices of women and other members of under-represented groups. if you stumble on a link spoken in such a voice and think “I’m not sure Colin would be interested” or “I don’t want to bother him” — I’ll tell you right now, it’s no bother and I’m certainly interested.

That’s all I’ve got for this week. If you have friends and/or colleagues who would enjoy Double Maths First Thing, do send them the link to sign up — they’ll be very welcome here.

If you’ve missed the previous issues of DMFT or — somehow — this one, you can find the archive courtesy of my dear friends at the Aperiodical.

Meanwhile, if there’s something I should know about, you can find me on Mathstodon as @icecolbeveridge, or at my personal website. You can also just reply to this email if there’s something you want to tell me.

Until next time,

C

Mathematical Objects: An object with Tai-Danae Bradley

By Katie Steckles and Peter Rowlett. Posted December 6, 2024



A conversation about mathematics inspired by … an object. Presented by Katie Steckles and Peter Rowlett, with special guest Tai-Danae Bradley.

Katie mentions Peter’s The unplanned impact of mathematics, free to read at Nature.





Podcast: Play in new window | Download

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The curious mathmo talks to David Roberts

By Christian Lawson-Perfect. Posted June 23, 2017

Way back at the end of last year I put out a call to mathematicians I know: hop on Skype and chat to me for a while about the work you’re doing at the moment. The first person to answer was David Roberts, a pure mathematician from Adelaide. 

We had a fascinating talk about one thread of David’s current work, which involves all sorts of objects I know no more about than their names. I had intended to release this as a podcast, but the quality of my recording was very poor and it turns out I’m terrible at audio editing, so instead here’s a transcription. Assume all mistakes are mine, not David’s.

If you’ve ever wanted to know what it’s like to work in the far reaches of really abstract maths, this is an excellent glimpse of it.



DR: I’m David Roberts, I’m a pure mathematician, currently between jobs. I work – as far as research goes – generally on geometry and category theory, and the interplay between those two. And also a little bit of logic stuff, which I thought I’d talk about.

Review: Cakes, Custard and Category Theory by Eugenia Cheng

By Katie Steckles. Posted June 25, 2015



We’ve often mentioned category theorist and occasional media-equation-provider Eugenia Cheng on the site, and she’s now produced a book, Cakes, Custard and Category Theory, which we thought we’d review. In a stupid way.