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Aperiodical News Roundup – July 2021

Here’s a round-up of the latest mathematical news from the month of July 2021.


The Society for Industrial and Applied Mathematics, SIAM, has announced the winners of its 2021 prizes. Winners include: student paper prizes to Yingjie Be, Michelle Feng and Yuanzhao Zhang; the George Pólya Prize for Mathematical Exposition to Nick Higham; and the John von Neumann prize to Chi-Wang Shu.

The Institute of Mathematics and its Applications, the IMA, has also announced some prize winners.

And since we’re talking about mathematicians winning awards, mathematician Anna Kiesenhofer has been awarded a gold medal in the women’s cycling road race at the Tokyo Olympics. For more information, read her 2016 paper Noncommutative integrable systems on b-symplectic manifolds (actually, it may not mention the Olympics at all, sorry).


Controlled study shows link between musical and mathematical ability. The paper is published in the Journal of Research in Music Education. (via MAA)

Laurent Fargues and Fields Medalist Peter Scholze have created “a long-desired bridge between the arithmetic and geometric sides of the Langlands program”, warranting a writeup in the always-excellent Quanta Magazine. (Via @KSHartnett)


If one science communication video contest run by a famous YouTuber this year wasn’t enough, Grant Sanderson (aka 3blue1brown) is running a Summer of Math Exposition. Submit an “explainer of math” to be in with a chance of a $1,000 prize. Imagine the Big Internet Math-Off, but with less voting and an actual prize. Grant announced the competition with a video titled “Why aren’t you making math videos?”:

Because we’re tired, Grant. We’re so tired.

The IMA Black Heroes of Mathematics 2021 conference will take place on the 5th and 6th of October. The vision of the conference is “To celebrate the inspirational contributions of Black role models to the field of Mathematics and Mathematics Education”. The event will include technical talks by internationally renowned Black speakers, incorporating details of their career paths and experience.

Other news

The Protect Pure Maths Campaign, funded by private donations and run by a PR firm in collaboration with the London Mathematical Society, aims to promote and protect pure mathematics research. The family of Alan Turing have added their support to the campaign, to protect what is described in this article in the Guardian as ‘blue skies maths’.

The IMA has announced they’re forming an alliance to create new professional standards for data science.

“The Alliance for Data Science Professionals is defining the standards needed to ensure an ethical and well-governed approach so the public, organisations and governments can have confidence in how their data is used.”

The alliance consists of the Royal Statistical Society (RSS), BCS, The Chartered Institute for IT, the Operational Research Society, the Institute of Mathematics and its Applications, The Alan Turing Institute and the National Physical Laboratory (NPL), supported by the Royal Academy of Engineering and the Royal Society.

Robert Moses, founder of math literacy promotion charity The Algebra Project, has died. The announcement on the project website includes a moving tribute:

“His transition to that higher level only inspires us all to love, struggle and live with and for our people as he did, as we continue to work to realize Bob’s vision of “raising the floor of mathematics literacy” for all young people in the United States of America.”

Brands are at it again with their weird unnecessary anti-maths schtick: take this recent effort from Specsavers in which they state algebra is hard (which it can be sometimes), but also imply it’s ‘silly’, which is pretty short-sighted of them (LOL). Also this month, IMA President and World’s Most Interesting Mathematician Nira Chamberlain has been hassling sofa chain DFS about their TV commercial in which a boy shouts ‘I HATE MATHS’ repeatedly – which may actually have resulted in a change to the broadcast version (and good work if so!). It turns out that calling out this kind of thing sometimes gets results.

And finally, it’s been anounced that the theme for the International Day of Mathematics 2022 will be “Mathematics Unites” (via Nalini Joshi).

A lullaby sequence

A baby in a pram rolling over a sequence of numbers

My son was born last September. While he doesn’t hate sleep as much as his sister did, he still needs a bit of help to drop off.

I’m not at all musically inclined, and I seem unable to remember more than a couple of lines from wordy songs (my version of “Papa’s gonna buy you a mockingbird” rapidly veers into nonsense as I try to think of a rhyme for the next line), so when the girl was little I hit upon the strategy of singing counting songs to lull her off to sleep. a collection of ambiguities, inconsistencies and unpleasant conventions in notation

I’m now the owner of, thanks to my past self’s successful campaign of Twitter peer pressure against my more recent self.

My aim is to collect examples of conventions in mathematical notation that lead to ambiguities, inconsistencies, or just make you feel yucky. This is largely a result of me wishing I had something to point to whenever I see $\sin^2$ or one of those viral “puzzles” relying on BODMAS.

I’ve set it up as a wiki, so you can edit it too. So far, it’s got a few dozen pages on some of the things that have troubled me over the years, along with some contributions from some of my maths pals, such as “There is no function application symbol”, “Parentheses are overused”, and “Juxtaposition means combine in the obvious way”.

My aim is to describe conventions, without prescribing a correct notation. Whenever I tweet a question about a notational convention, my aim is to find out the range of different opinions that people hold about it. I often get replies arguing authoritatively for a particular correct answer, usually followed up by an equally certain reply from someone else arguing for the opposite. Like all language, mathematical notation is just something we make up to help express our ideas, and opinions, abuses of notation, lapses in memory and convenience all work against consistency and clarity.

I’d like the site to collect all these difficult aspects of notation, so that they don’t trip up someone who thought they might have an easy day doing maths.

So, have a look, and if you can help to build it out, I’d be very happy!

Aperiodical News Roundup – May 2021

Here’s a round-up of mathematical news from the month of May.

The film Words of Women in Mathematics in the Time of Corona showcases the words of 86 women of mathematics from 37 countries, speaking in 25 languages, on their experience during the pandemic. The project website says:

This pandemic has indeed made women, and in particular women in mathematics, more invisible than ever and we hope that this project will contribute to letting them be heard and seen.

(via Tony Mann)

Mathematician, IMA president and one-time World’s Most Interesting Mathematician Nira Chamberlain appeared on Jim Al-Khalili’s excellent radio show The Life Scientific, and talked about how mathematics can solve real-world problems.

The adventures of Mathina. An illustration showing two children in a rural landscape, with a castle in the distance. Two buttons, labelled "Start Exploring!" and "Introduction"

Mathina is an interactive story book, “based on story-driven experiences, in which children and young learners encounter fictional characters that find themselves in mathematical adventures”. It looks cool! (via Martin Skrodzki)

I is a Strange Loop is a theatrical play, written and performed by mathematician Marcus du Sautoy and mathematician/actor Victoria Gould (formerly Polly off Eastenders). A performance was streamed live on 25th May, and available to watch back on the Oxford Uni maths YouTube channel. The script of the play is also available to buy in book form.

Jean-Michel Bismut and Jeff Cheeger

The winners of the Shaw Prize, “an international award to honour individuals who have recently achieved distinguished and significant advances in their respective fields”, have been announced for 2021, including the Shaw Prize in Mathematical Sciences. This is awarded in equal shares to Prof Jean-Michel Bismut and Prof Jeff Cheeger (pictured right, floating in an abstract mathematical universe), “for their remarkable insights that have transformed, and continue to transform, modern geometry”.

And finally, Turkish mathematician Tuna Altinel has his passport back after two years of fighting the Turkish courts. Altinel was detained by Turkish authorities and his passport confiscated on the grounds of “membership in a terrorist organisation”, due to his attempts to promote peace and support human rights as part of the group Academics for Peace.

More information in this piece from Inside Higher Ed

See also: The case of Azat Miftakhov.

(via Jordan Ellenberg on Twitter)

Aperiodical News Roundup – April 2021

Top news this month: Pure mathematicians at Leicester have opened a GoFundMe to pay for legal support in their fight to keep their jobs. The London Mathematical society has published a letter making the case for pure maths at Leicester, and there’s a petition you can sign.


Hannah Fry has a new TV show about maths and sport, on BT Sport and YouTube, called It’s A Numbers Game (or IT’S A NUMB3R5 GAME, if you believe the logo). She’s joined by Pippa Monique, Ugo Monye, Andrew Mensah and Dr Nick Owen. It’s on each Saturday on both BT Sport and YouTube. There are some resources for kids aged 5 to 14 on Twinkl, to go with the show.

Erasmus EUR2 coin


Dr. Marie Davidian is the recipient of the 2021 Marvin Zelen Leadership Award in Statistical Science. (via Harvard Biostatistics)

UK mathematicians Yuhka Machino and Jenni Voon earned gold medals at the 2021 European Girls’ Mathematical Olympiad, and the UK team as a whole finished third. (via the UK Mathematics Trust)


The Institute of Mathematics and its Applications is again running a series of online talks.

The first talk at the 6th May event will be from Nick Higham who has been awarded the Gold Medal award in recognition of outstanding contributions to mathematics and its applications. This will be followed by Jane Leeks and David Abrahams discussing future developments in mathematical sciences knowledge exchange.

There will be a couple more talks on the 25th of May to do with modelling and Covid-19.

More information: IMA Mathematics Online series

The London Mathematical Society is offering two summer placements – a Library and Special Collections Summer Placement (working with the LMS’s special collections) and an Equality and Diversity – Success Stories Placement (putting together profiles of successful mathematicians), both of which are paid hourly at three days a week for 8 weeks over the summer, and would suit prospective postgraduates with an undergraduate degree.

More information: Jobs at the LMS

The International Congress of Mathematicians is running a surprising maths videos contest. Prizes include a grant to attend ICM 2022 in St Petersburg, which won’t be much use to LGBT+ mathematicians, whose existence in Russia is illegal, or Azat Miftakhov, a student at Moscow State University who has been detained by Russian authorities for two years. If that doesn’t faze you, the ICM has produced an example of a surprising maths video:

Proof news

Kelsey Houston-Edwards writes in Quanta magazine about a proof of the Erdős-Faber-Lovász conjecture on colouring hypergraphs. The preprint by Dong Yeap Kang, Tom Kelly, Daniela Kühn, Abhishek Methuku and Deryk Osthus is available on the arXiv.

Also in Quanta magazine (if you can pay people to write maths news, they write maths news! Who knew?), Erica Klarreich writes about a counterexample to the unit conjecture on group algebras, presented at the end of a talk by Giles Gardam, and Steve Nadis writes about a recent proof of a special case of the Erdős-Hajnal conjecture in graph theory. That guy Erdős sure made a lot of conjectures.

Over on the, where seekers of new and exciting prime numbers hang out, it’s been reported that a new probable prime repunit has been found – it’s got a record 5794777 decimal digits, all of which are the digit 1. (via Ed Pegg)

Other news

Version 3.0 of SnapPy, program for studying the topology and geometry of 3-manifolds, has been released. (via Jordan Ellenberg)

Early Family Math is a new free maths resource website for children from 6 months to 6 years old. At the moment it has a lot of resources for activities, and some maths story books. They say that videos are forthcoming.

And finally, there’s a fundraiser for Mathematicians of the African Diaspora, which hosts the largest searchable database of mathematical scientists of the African Diaspora in the world, and is looking for funding to expand its database and reach a wider audience so it can continue to inspire the next generation of Black mathematicians. (via Edray Goins)

My robot draws TeX

For my birthday I got an EleksDraw pen plotter. It’s a cheap and cheerful example of the form: a pair of orthogonal metal rods with a pen on the end, attached to electric motors. The idea is that I can connect it to my computer and the computer can direct it to draw things. It arrived as a kit, so first of all I had to descend from the astral plane of pure thought and – shudder – screw the bits together.

The #plottertwitter hashtag is a constant source of inspiration, where people around the world share pictures of the amazing, beautiful things they’ve made their pen plotters draw, often with the AxiDraw plotter, which differs from mine in that nobody seems to have had to attach 200g of batteries as ballast to the pen holder to overcome friction on the knacky sliding rail.

My pen plotter. The end closest to the camera is the pen holder, which has had two AAA and one C battery stuck to it with electrician's tape.

The basic idea of a pen plotter is that the pen holder is free to move in the plane, constrained by the lengths of the two axes. If there’s a pen in the holder and paper underneath as it moves, then a drawing happens. The pen holder can move up and down, to lift the pen away from the paper so it can move without drawing.

The instructions you can give the plotter are quite straightforward: move in a straight line to these coordinates; move the pen up or down; move back to the ‘home’ position. It’s a lot like the turtle drawing robot I played with in primary school.

A robot turtle. Its shell is clear plastic, through which you can see lots of electronics and a pen holder.
A Valiant turtle robot, similar to the one I used in primary school. Photo from National Education Network.

You can either directly write a list of instructions for the plotter, or write some code that takes a vector image and produces a corresponding set of instructions. SVG is a widely-used vector graphics format, so it’s a common choice of input for pen plotters.

This was very pleasing to watch.

So I was playing around with my pen plotter, getting it to draw space-filling curves and geometrical diagrams, when I decided that I should get it to draw text. It turns out that there are a few ready-made “fonts” for plotters that give paths to write letters with strokes instead of filling in shapes, so that was nice and easy.

But then I wanted to write mathematical notation, and I remembered: MathJax has an SVG output! It didn’t take long to write a bit of JavaScript that takes some maths written in LaTeX and gets MathJax to produce the corresponding SVG code and insert it into the picture, ready for my plotter to draw.

The remaining problem is that MathJax’s fonts produces shapes that should be filled in, which is easy on a computer screen, but the pen plotter just draws their outlines. That’s not much of a problem, though: I just had to trace over the symbols in Inkscape, and replace each instance of a MathJax symbol with my single-stroke traced version.

The pen plotter hovering over a piece of paper, on which is drawn some mathematical notation. Each of the symbols has been drawn in outline.
Success! But it looks like a mathematical crime scene with those outlines.

There are squillions of symbols in the TeX fonts, and I didn’t want to have to trace them all before I could draw anything, so I decided to do it bit-by-bit. I added a step to my MathJax → SVG tool to capture any symbols in the output that hadn’t been traced yet and produce an SVG file I could load into Inkscape. After tracing over those symbols, my code absorbed them into its library of replacements. I wasn’t too careful to be precise with my traced symbols – I wanted it to look as much like handwriting as I could manage.

Some mathematical notation drawn in a jumble on a page. The symbols are drawn with single strokes instead of outlines.
My first few traced symbols. They already look a lot better, and more like handwriting, than the standard TeX fonts.
A passage of text with inline mathematical symbols drawn on paper.
Starting to draw TeX inline with plain text. The font I chose for the plain text made it look a bit too much like the product of a typewriter. The text is from Éléments de Géométrie of 1885 by L’Abbé M. Reydellet, another birthday present.
Another passage of mathematical text. This time the plain text is drawn in a style that looks more like natural handwriting.
This looks much better! The text is drawn from Philip Ording’s brilliant 99 Variations on a Proof.

The fantastic thing about MathJax is that it does a lot of work to match its output with the size of the surrounding plain text, so the results looked really good straight away.

I decided to draw some mathematical postcards to send to my maths pals. On one side I drew a picture, and on the other side I wrote a passage of text about it, often with plenty of mathematical notation.

Eight postcards drawn on colourful paper. They each feature a different mathematical diagram.
The “front” sides of my first batch of postcards.
Eight postcards, each with a passage of text including inline and standalone mathematical notation.
The “back” sides, with explanations of the diagrams. You can see a few places where the pen went awry or failed to drop down, so I had to make it draw over some sections a couple more times.

I’m particularly pleased with this formula for the length of a toilet roll, drawn from the paper How long is my toilet roll? – a simple exercise in mathematical modelling by Peter R. Johnston:

I’ve put all of my plotter-related code online. If you just want to make your own postcard, here’s a tool you can use to write a postcard with mathematical TeX.