There seem to be a lot of numerical coincidences bouncing around concerning the new year 2025. For example, it’s a square number: \( 2025 = 45^2 \). The last square year was \(44^2 = 1936\), and the next will be \(46^2=2116\).
The other one you have likely seen somewhere is this little gem: that 2025 equals both \((1+2+3+4+5+6+7+8+9)^2\) and \(1^3+2^3+3^3+4^3+5^3+6^3+7^3+8^3+9^3\).
The UK Government have announced the latest list of honours, and we’ve taken a look for the particularly mathematical entries. Here is the selection for this year – if you spot any more, let us know in the comments and we’ll add to the list.
Alison Etheridge, Professor of Probability, University of Oxford, and President, Academy for the Mathematical Sciences, becomes a Dame for services to the mathematical sciences.
Francis Keenan, Professor (and former Head of School of Mathematics and Physics) at Queen’s University Belfast. Appointed MBE for services to higher education.
John Westwell, Director, System Leadership, National Centre for Excellence in the Teaching of Mathematics. Appointed MBE for services to education.
Adam McCamley, Senior Analyst, Liverpool City Council. Appointed MBE for services to social care data.
Jineon Baek claims a resolution to the moving sofa problem. This considers a 2D version of turning a sofa around an L-shaped corner, attempting to find a shape of largest area. (There are some nice animations at Wolfram MathWorld.) Baek offers a proof that the shape above, created by Joseph L. Gerver in 1992, is optimal.
One thing that’s new, apart from the prime itself, is that the work was done on a network of GPUs, ending “the 28-year reign of ordinary personal computers finding these huge prime numbers”. Also this was the first GIMPS prime discovered using a probable prime test, so the project chose to use the date the prime was verified by the Lucas-Lehmer primality test as the discovery date. In other computation news, the fifth Busy Beaver number has been found, as well as 202 trillion digits of pi.
Finite Group is a friendly online mathematical discussion group which is free to join, and members can also pay to access monthly livestreams (next one Friday 20th December 2024 at 8pm GMT and recorded for viewing later). The content isn’t at the level of the research mathematics in this post, but we try to have a fun time chatting about interesting maths. Join us!
A brief update about the state of social media. A couple of years ago, I wrote about the decline of Twitter and how I was going to consciously shift my activity to Mathstodon. Just over a year ago, we launched The Finite Group, a members’ club for mathsy people, partly inspired by the collapse of social media. We recently updated this to include a free membership.
Since then, I’ve ended up in an awful state where I’m somewhat engaging with X, Mastodon, Bluesky and Threads, but not engaging much with any. If I have something to broadcast, say a new blog post, I’ll put it on all four. If I have something to say or fancy a chat, I might put it on Mastodon. What’s happening just now is that more people seem to have decided to leave X for Bluesky. Will that stick? I don’t know, but it’s nice to see people who I used to see on Twitter being active, and for whatever reason those people haven’t got on with Mastodon, so it seems promising (from that point of view, though it’s not an ideal place to be).
Here’s my current position:
If I want to have a natter about something maths, the absolute best place for that is The Finite Group. You can join for free and get access to a friendly online chat community run via Discord. (There are also paid memberships where you get to watch livestreams.)
I’m going to stop looking at Threads. Things I post there get very little engagement, and I don’t see much I’m interested in. It’s also a regular little irritant because it keeps alerting me it has found something of interest to me, which turns out to be of no interest whatsoever.
I continue to log into X because there are some large organisations there whose updates I would like to receive. I have to wade through Elon’s thought of the day and crypto ads to get there and I hope in time this will stop being part of my life. Will I continue to post stuff I do there? I’m not sure, to be honest.
