A very occasional blog about maths things which interest me.
Welcome to Carnival of Mathematics issue 249! Before we dive into our monthly assortment of maths, it's customary to provide some fascinating information about the issue number. So I asked ChatGPT for interesting nuggets abut the number 249. ChatGPT tells me that 249 is not prime, that it is 15^2+24 and 24 is close to a square number, and that its digital root is 6. None of that excited me, so I…
I make no claims to be a statistician (though I recently read a textbook* on Bayesian probability from cover to cover) and I apologise for any errors in this post: my excuse, in the words of Dr Johnson, is "Ignorance, madam, pure ignorance". But having made that caveat, I feel that I think like a Bayesian when I am waiting for my bus home. If there are a lot of people waiting, I reduce my estimate…
I've reconstructed a puzzle which I remember being amused by when I came across it in a school textbook. We expect that if you add a quantity to itself, and then take half of the result, you get the origal quantity. That doesn't happen here. Background: Imperial measurements. One rod (or perch) is 5.5 yards. 1 chain is 4 perches or 22 yards. 1 furlong is 10 chains or 220 yards One mile is 8…
Earlier this week, on 24 February, my Wordle streak of over 200 successes came to a sad end. (For those who don't know the game, each day one has to deduce a five-letter word in at most six guesses, learning after each attempt whether each letter is correct and in the correct place, or correct but out of position.) I play the hard version, which requires that each guess be consistent with the…
This isn't really maths (except in so far as all computing is maths) but I am going to vent a couple of frustrations regarding laptops. First, I am sure there is a good reason for this design feature and I would be delighted if someone could enlighten me. Here is part of the keyboard of this laptop: Now, note the position of the on/off switch (lit up in the photo). It's in the middle of the top…
I have a horrible feeling that a long time ago I believed, and perhaps even tried ti persuade others, that mathematics is different from other forms of human knowledge and endeavour. The works of Shakespeare, Beethoven and Rembrandt, for example, are contingent on human attributes, such as our language and emtions and our senses of sight and hearing. Other species, however evolved, would be…
I'm delighted to host for the second time the monthly Carnival of Mathematics for August 2023. Information about the Carnival and links to previous issues can be found at The Aperiodical . This is Carnival 218, and it is customary to begin with some facts about the issue number. Following my immediate predecessor Vaibhav at DoubleRoot , and using the approach currently being adopted by some…
Following the 24 Hour Maths Magic Show two years ago, this coming weekend brings the 24 Hour Maths Game Show! Starting at 7pm on Friday 28 October there will be 24 hours of mathematicians presenting mathematical games, or games about mathematics. For details of the stellar line-up and the exciting fun in prospect see the event website . The event is raising money for four excellent charities -…
How did mathematicians cope with the Covid lockdowns? COVIDIARY of Mathematicians is a new book published by the Mathematical Society Archimedes of Belgrade. It presents diaries from April 2020 of seven mathematicians in different parts of the world - Tiago Hirth (Lisbon), Guido Ramellini (Barcelona), James Tanton (Phoenix), Jovan Knezevic (Belgrade), Kiran Bacche (Bangalore), Sergio Belmonte…
Emma Raducanu's feat of winning the US Open as a qualifier, without dropping a set in her ten matches, was astonishing. In feature articles this summer, during and after Wimbledon, her A-level achievements this summer, and especially her A* grade in A-level Mathematics, have been reported, Is there a connection between her tennis accomplishments and her study of maths? Now, mathematics implicitly…
Here's a variation on my previous post - another piece of hand-waving probabilistic reasoning, which I think is basically correct, but I suspect many will disagree. A long time ago I used to do the challenging weekly cryptic crosswords in The Listener magazine. ( The Listener has been defunct for many years, though I think the crossword continues in The Times .) The story was that if no-one solved…
When I was an undergraduate, I was walking through the town centre one morning when a journalist from the student newspaper asked my views on the Rag Mag that had just appeared. When the report came out, six students' views were quoted. Three of the six happened to be from the same cohort of six maths undergraduates at my college. My Director of Studies concluded (jokingly) that this…
I spent last weekend at the online conference Tomorrow's Mathematicians Today , hosted by the University of Greenwich and the Institute of Mathematics and its Applications. This is a conference for undergraduate mathematicians to present to their peers on mathematical topics that excite them - this might be their own project work, or something they have come across in the curriculum or outside it…
I haven't watched the Netflix series The Queen's Gambit , but (prompted by a review in Private Eye ) I've just read Walter Tevis's 1983 novel on which it is based. (I'm a reader rather than a viewer by inclination.) It's an interesting book, which I thought well worth reading. Now, I know I am missing the point, but there were a couple of things I found irritating. first of all I found the…
Peter M. Neumann (1940-2020) (Photo by Bert Seghers, Wikimedia Commons, Public Domain) A very sad post - the mathematician Peter M. Neumann died on Friday 18 December of Covid-19/ Peter was my moral tutor when I was a postgraduate student at The Queen's College, Oxford, and like many others I was enormously influenced by him. I was very lucky as a student to have wonderful support from several…
So over the last few weeks I have performed a couple of mathematical magic tricks which I have put on my Youtube channel. As part of the 24 Hour Maths Magic Show , when I was hosted by the amazing Chris Smith, I performed a trick based on the curious phrase "David Lovel in yon abbey". You can watch the trick and find out how it relates to the phrase. At the virtual MathsJam 2020 Gathering , with…
The mathematician John Horton Conway died just over a week ago. (I recommend Siobhan Roberts's biography Genius at Play .) I' intend to write a post later about what his book On Numbers and Games meant to me, but in this post I will share a couple of memories of Conway. I emphasise - these are memories and their accuracy is not guaranteed. First,a personal story of how I was caught out by his exam…
I' am one of these annoying people who loves self-reference. I had a sign saying "Why can't anyone these days do anything properyl" in my student room: now I wear a T-shirt labelled "Prefectionist", so my sense of humour hasn't developed. Books which I loved as a student (and still do) are Patrick Hughes and George Brecht's Vicious Circles and Infinity and Douglas Hofstadter's Gödel, Escher, Bach:…
I have always underestimated the interest value of the Tower of Hanoi problem. If you don;t remember the puzzle, there are three positions for piles of discs of different sizes, starting with all discs piled from smallest to largest on one pile (in this case the leftmost). The Tower of Hanoi The problem is to move disks so that the whole pile is now in the rightmost position, but one can only move…
Another New Year, another resolution to write more blog posts. We'll see. A mathematician delivering the Royal Institution Christmas Lectures is always something special. Hannah Fry's three lectures this year were rather different from Christopher Zeeman's classics. Rather than one person directly talking to the audience for the full hour each time, she brought in guests for short interviews,…
So in ten days time the University is hosting Greenwich Maths Time, the 2019 IMA Festival of Mathematics and its Applications. The Festival takes place on Tuesday 25 and Wednesday 26 June. Everything is free! The weather forecast is currently fine and we are looking forward to a feast of mathematics. The programme and booking details can be found at the Festival website…
The Big Internet MathOff is now taking place. Sixteen mathematicians are competing in a knock-out tournament to present the most interesting piece of mathematics. With the final two matches of the first round now taking place, there has already been a wealth of fascinating mathematics presented. Christian Lawson-Perfect deserves huge thanks for creating this wonderful showcase of exciting maths.…
I was lucky enough to attend a meeting organised by the British Society for the History of Mathematics on "The History of Cryptography and Coding". It was a quite exceptional meeting - six excellent talks. As one of the other audience members said, I learned something from every talk, and a lot from several talks. (Anyone who goes to these events will know that this isn't always the case.) The…
A couple of weeks ago, I got onto my morning bus, climbed the stairs, holding on as the bus lurched forward, and sat down, to hear for the first time the new announcement "Please hold on: the bus is about to move", introduced by TfL (Transport for London). Over the next few days this announcement was widely ridiculed. It was broadcast after every stop, but often - in my experience almost always -…
Here is my overdue post on last weekend's MathsJam gathering. MathsJam is always a wonderfully exciting and enjoyable weekend, and this one was particularly good. I can honestly say that I enjoyed every talk, and was entertained, surprised and educated in roughly equal measures. I'm nervous about selecting highlights, because almost everything was a highlight, and my list inevitably leaves out…