Next weekend, a group of maths presenters will be getting together some mathematicians, magicians and other cool people to put on a 24-hour long online YouTube mathematical magic $x$-stravaganza. Each half-hour will feature a different special guest sharing a mathematical magic trick of some kind, and across the day there’ll be a total of 48 tricks for you to watch and puzzle over.

Currently confirmed guests include:

- Stand-up Mathematician
**Matt Parker** - Professional speed Rubik’s cuber
**Sydney Weaver** - Popular science author
**Simon Singh** - University Challenge star
**Bobby Seagull**

The show will be live streamed starting from **9pm on Friday 30th October** and run through until **9pm on Saturday 31st**, and you can sign up for a reminder of when it’s happening by following the **Twitter account **@24hmaths, or by visiting the **website** at 24hourmaths.com and putting in your email address for a one-time reminder email.

The show will run alongside comedian Mark Watson’s 24-hour live comedy show Watsonathon, which will be a separate concurrent livestream, with some crossovers where the two shows chat to each other. Both events will be raising money for the charity Turn2Us, which helps people in low-income jobs & gives out emergency loans, including supporting comedians and other performers who have little/no income at this time.

The team is still looking for a few trick presenters, and if there’s anyone you could suggest that might be able to share an interesting bit of maths, you can contact them through Twitter by sending DMs to @24hmaths, or you can email us and we’ll pass the message on.

]]>A conversation about mathematics inspired by a Klein bottle and Mathsteroids. Presented by Katie Steckles and Peter Rowlett, with special guest Matthew Scroggs.

]]>The Carnival rounds up maths blog posts from all over the internet, including some from our own Aperiodical. See our Carnival of Mathematics page for more information.

]]>A conversation about mathematics inspired by a hat. Presented by Katie Steckles and Peter Rowlett.

]]>Monday 26th – Tuesday 27th October; Online Conference held via Zoom

The British Society for the History of Mathematics, The International Centre for Mathematical Sciences, the Institute of Mathematics and its Applications and the London Mathematical Society, are holding a two day conference on Black Heroes of Mathematics. The Vision of the conference is “To celebrate the inspirational contributions of black role models to the field of mathematics”.

There will be a mixture of technical talks and a testimonial dimension from Black speakers, with a balance of career stage and gender. Speakers include Professor Edray Goins, Professor Nkechi Agwu, Professor Tannie Liverpool and Dr Angela Tabiri. Pre-recorded talks will be available a few hours ahead of the sessions, with a live Q&A/discussion.

Provisional programme – Registration form

Thursday 1st – Friday 2nd October; Online Conference via Zoom

The London Mathematical Society and the Institute of Mathematics and its Applications will hold their next Joint Meeting online on 1st-2nd October 2020. This year’s topic is “Topological methods in Data Science”.

This event is part of the ICMS Online Mathematical Sciences Seminars, and a full programme will be released shortly.

Provisional programme – Registration

MathWorks Math Modeling (M3) Challenge is a free, Internet-based applied maths competition for high school juniors and seniors in the US, and is now open to sixth form students in England and Wales. Participants work in teams of 3-5 to solve an open-ended real-world problem within 14 hours. Many free resources and software licenses are offered to help students prepare.

The top ranking team in England and Wales will be invited to the final event in New York City on April 26, 2021, all expenses paid. Rules, practice problems and other resources are available on the M3 challenge website.

Maths education body MEI is running a free competition for students of A-level Mathematics and equivalent, starting on 5 October. Ritangle is made up of 24 questions released over the months to December, and the winning team get a trophy, subscription to teacher resource site Integral (which supports, and is an anagram of, the competition), and and a hamper of maths goodies.

Last year’s Ritangle competition was entered by almost 600 teams, and questions from previous years are all available.

]]>European Women in Mathematics, an international association of women working in mathematics in Europe, has written an open letter encouraging universities and institutions to take action to lessen the disproportionate impact of the COVID pandemic on women in mathematics. Advocating a flexible approach in these uncertain times, the letter seeks signatures from anyone who supports their aim – to ‘shape smart policy to recruit and retain a diverse group of talented young scientists.’

The Breakthrough Prizes (if you’d forgotten, those are the ones founded and awarded by a collection of incredibly rich people to recognise achievements in maths and science by giving people ludicrous piles of money) for 2021 have been announced. Mathematician and Fields medalist **Martin Hairer** has been awarded the Breakthrough Prize in Mathematics, which comes with a cash gift of $3m and a nice trophy, for his “transformative contributions to the theory of stochastic analysis, particularly the theory of regularity structures in stochastic partial differential equations”.

The board also awards six New Horizons Prizes of $100,000 to early career researchers in maths and physics. The maths winners this year were **Bhargav Bhatt** of the University of Michigan, **Aleksandr Logunov** from Princeton University and **Song Sun** of UC Berkeley, who are working in areas including algebra and geometry.

From this year Breakthrough are also awarding three Maryam Mirzakhani New Frontiers prizes of $50,000 to women mathematicians for early-career achievements, which went to **Nina Holden** of ETH Zurich, **Urmila Mahadev** at Caltech and **Lisa Piccirillo** from MIT, for work in geometry, quantum computing and knot theory.

Winners of the 2021 Breakthrough Prizes in Life Sciences, Fundamental Physics and Mathematics Announced, on the Breakthrough website

Four from MIT awarded 2021 New Horizons in Physics and New Frontiers in Mathematics prizes, on the MIT News website

Mathematician, cosmologist and theoretical physicist John Barrow passed away this month from colon cancer. As well as a distinguished research career, publishing more than 500 journal articles, he worked extensively in communicating maths, through lectureships, public talks – including at 10 Downing Street, Windsor Castle and the Vatican – a long list of popular maths and astrophysics books, and his work with the MMP. He was recognised for this work with, among many other honours, the IMA’s Zeeman Medal and the Royal Society’s Faraday Prize.

The late Ron Graham, who passed away in July, was a fountain of mathematical wisdom. His widow, Fan Chung, is looking to collect some of these – if you know of any that have inspired you, add them to this thread.

Mathematician and author Vicky Neale is following up her brilliant book Closing the Gap: the quest to understand prime numbers with a second, Why Study Mathematics?. Aimed at students considering a maths degree, it gives an insight into what’s involved in a maths degree and why it’s a useful thing to have. It’s available to preorder now on the LPP website.

Mathemalchemy is a mathematical art collaboration between a group of 23 mathematicians/artists, as outlined in this teaser video:

The brainchild of mathematician Ingrid Daubechies and fibre artist Dominique Ehrmann, the project was planned to take place this year, but due to COVID, workshops planned in March and August were cancelled. The project will still go ahead, with plans for a physical installation at the end of the summer of 2021.

]]>Spreadsheets are wonderfully versatile, and the fact that I can now carry spreadsheets around on my phone, in my pocket, is a marvellous result of the smartphone boom. I’m always pleased to see so many people wandering around using spreadsheets on their phones (I assume).

So when my Aperiodicolleague CL-P sent me a link to his latest spreadsheet creation, I was pretty excited to find yet another application of spreadsheets – for modelling cellular automata! As we’ve previously written about on this site, cellular automata are systems that have a set of rules to determine how they change over time, on a cell-by-cell basis (spreadsheets are really the natural choice here). While many automata, such as Conway’s famous Game of Life, are 2-dimensional, that’s slightly difficult to represent on a spreadsheet, as you’d need a separate sheet for each point in time. 1-dimensional automata can be displayed on a spreadsheet though, by simply using the top row to represent the cells you’re starting with and then iterating time down the sheet.

CL-P’s spreadsheet models the famous Rule 30 cellular automaton, named for the specific rule it encodes. Stephen Wolfram, of Wolfram who brought you the maths programme Mathematica and many other cool maths things, named the set of Elementary Cellular Automata rules (0 to 31), each using a different pattern of outputs. The rules tell you how the cells in the row above determine the next row – each triple of three cells determines the value of the cells below, and each cell is allowed to be ‘on’ or ‘off’ (much like in Conway’s Game of Life, where the cells are ‘alive’ or ‘dead’). Since there are 8 possible combinations of on/off across 3 cells, the rule is encoded by knowing whether each of the 8 combinations results in the cell below being ‘on’ or ‘off’. These 8 on/off values determine a binary number less than 32, and the rule is named after the number given by the set of on/offs it uses, as 0/1 digits.

Of the 31 possible rule-sets Wolfram determined in this way, 30 is probably the most well-known, mainly because it’s the most interesting. $30 = 00011110_2$, which means if the number given by the three cells above as binary digits is 0,6,7 or 8 then the cell below should have a 0, and if not then it should have a 1.

Some of them end up dying a death pretty quickly (rule 0 is particularly boring – whatever you start with, everything in the second row is dead, and everything after that is dead forever). Rule 30 however, gives a pleasing pattern of shapes and even if you just start with a single ‘on’ cell in the top row, propagates a pattern across the whole sheet. Christian’s found a way to incorporate the statement of Rule 30 into a single formula:

=if(mod(4*[cell above left]+2*[cell above]+[cell above right]-3,7)<4,0,1)

This says, if the three cells above left to right are A, B and C, then if $4A + 2B + C – 3 $ (the binary number given by the numbers above, minus 3) is less than $4 \mod 7$ – so, if the number above is 0,6,7 or 8, then don’t colour the cell, and if it’s not then do colour the cell. Conditional formatting is used to make cells with a 1 in turn green, and cells with a 0 will remain white.

Christian’s sheet is here: CP’s Rule 30 spreadsheet

If you’d like to play with it, you can make a copy of it in your own Drive and edit there – we’ve left this one as view-only so you can always come back and get an undamaged version if you make a mess of things. Try starting with different combinations of 0/1 across the top, and make sure you give it a little time to calculate the rest of the sheet – it’s thinking pretty hard for a little phone!

]]>We spoke to Plus Magazine editors Marianne Freiberger and Rachel Thomas about their podcast, Maths on the Move.

**Podcast title: **Maths on the Move**Website: **plus.maths.org/podcast**Links: **RSS feed**Average episode length:** 25 minutes**Recommended episode: **Any of our latest series published since April 2020!

**What is your podcast about, and when/why did it start? **

The Plus podcast is a chance to meet the mathematicians behind new maths and its applications to our lives. We’ve covered issues surrounding COVID-19, maths and music, artificial intelligence, and some more esoteric aspects of theoretical physics — and all our episodes feature experts in the different fields. We first started producing podcasts way back in 2007, but this year have relaunched the podcast with a new format.

**Who publishes your podcast?**

The Plus podcast is published by Plus Magazine, a free online magazine aiming to open a door to the world of mathematics for any curious minds. Apart from podcasts, Plus also runs articles, interviews, news stories, reviews and videos about all aspects of mathematics and its applications. We’re part of the Millennium Mathematics Project, an educational initiative based at the University of Cambridge.

**Who is the intended audience for the podcast? **

Anyone who is curious about maths and the world: including the general public, older secondary school students, and their teachers.

**What is a typical episode like?**

A typical episode is about 25 minutes long, featuring Rachel and Marianne exploring a particular topic, including a discussion with an expert in the field. At the end of each episode we try to explain a mathematical idea (e.g. NP-hard problems) in one minute, complementing the Maths in a Minute Library on Plus. Podcasts are released roughly once a fortnight, though we’ve had a break over the summer. And if the ideas we discuss capture your interest, you can explore them further in accompanying articles on the Plus website!

**Why should people listen? Why is it different to other mathematical podcasts?**

Plus podcast is a chance for listeners to hear from the mathematicians behind the research themselves, following an accessibly introduction to the ideas we are covering. It also covers a huge breadth of topics – we have an extensive contact network throughout the world of maths, which means we can talk to mathematicians working in all sorts of areas, from Fields Medallists researching the furthest reaches of pure maths to epidemiological modellers. Alongside exploring individual bits of maths, our aim is to show the relevance of maths to all areas of life.

**What are some highlights of the podcast so far?**

From the recent series we particularly enjoyed working on our COVID-19 podcast back in the early days of the pandemic and the lovely audio tour of the La La Lab exhibition.

We also have lots of favourites from the archive of old episodes! One highlight was our report from the announcements of the Fields Medals and other prizes from Rio in 2018.

**What exciting plans do you have for the future? **

We are just about to start production up again, and we’re really looking forward to producing our next podcast that features both a magician and one of our favourite mathematicians. We’re also really looking forward to covering the virtual Heidelberg Laureate Forum later this month, as well as continuing our current involvement with the Infectious Dynamics of Pandemics programme put on by the Isaac Newton Institute.

Standard bunting (pictured above) takes the form of a regular pattern of shapes arranged along a ribbon, and often employs triangles, but we’re looking for you to decide how you interpret our challenge: to make this somehow be a fractal. We don’t want to bias your thought processes, so that’s all we’re giving you. **Fractal bunting**. *Fractal*. Bunting.

It’s up to you if your entry is a sketch on the back of a napkin, or if you’re keen, whether you make real actual bunting out of paper, card or fabric (or just some smaller bunting) and send us a photo. We’ll judge the entries based on fractal-y-ness, use of colour, creativity, mathematical satisfying-ness, and whatever other criteria we make up at the time. We’ll have a special guest judge, illustrator and friend of maths Hana Ayoob, to make sure we properly consider aesthetics and not just cold hard numbers.

You can **enter our competition on Twitter**, using the hashtag **#fractalbunting**, mentioning @Aperiodical in your tweet; if you don’t use Twitter, or don’t want to, you can **email your designs to root@aperiodical.com** with the subject line ‘Fractal bunting’.

The closing date for entries has been extended to **noon on 23rd October**, and we’ll announce the results the following week. Our favourite entry will win a signed copy of Here Come the Numbers, a rhyming book telling the story of numbers, illustrated by Hana and written by mathematician Kyle Evans.

In our constant quest to make sure people aren’t abusing maths too badly, we recently came across a new campaign from a certain corporate electronics giant, who have invented a washing machine with a little door in the door. A meta-door, if you will, so you can add extra items while a wash is going on.

Their plan to promote this was that they got a science/maths person to study the phenomenon of missing socks, and how starting from matching pairs and proceeding with standard laundry techniques, inevitably some socks become divorced from their partners – to try to figure out why this happens. We found the results of their efforts laughably entertaining, so we thought we’d share.

Firstly, enjoy this ridiculous infographic:

The equation, which is poorly typeset in the top right, appears to have been completely mangled by whoever made the infographic – I feel truly sorry for the poor mathematician who got themselves caught up in this, because that is so far from what they actually came up with it makes me want to cry. And not just because they’ve used a curly letter x in place of the times symbol.

The actual report they wrote (PDF) is linked to in amongst the press release, and it’s fairly thorough – they’ve studied a sample of around 30 people and asked them about their laundry habits, and come up with the a formula for the probability you’ll lose a sock in a given year.

They have, unfortunately, forgotten to put the formula in the document, between where it says “Missing sock phenomenon is predicted by the following formula:” and “The higher the resultant number the greater the probability that socks will go missing.”, which whoever typeset it presumably thought WAS the formula; luckily the accompanying press release actually has the equation in, so we can determine it’s:

\[ \textrm{Sock loss index} = (L + C) − (P \times A)\]

Here, the quantities are defined as:

$L$ = Laundry size, calculated by multiplying the number of people in the household (p) with the frequency of washes in a week (f); I imagine this assumes the washing machine is always full when run, since otherwise increasing the frequency of washes would just mean smaller loads

$C$ = Washing Complexity, calculated by adding how many types of wash (t) households do in a week (darks + whites) and multiplying that by the number of socks washed in a week (s)

$P$ = Positivity towards doing laundry, measured on a scale of 1 to 5 with 1 being ‘Strongly dislike doing clothes washing’ to 5 which represents ‘Strongly enjoy doing clothes washing’; as far as I can tell there are no SI units measured on a scale of 1 to 5, so I’m not convinced this is 100% scientific

$A$ = Degree of Attention, which is the sum how many of these things you do at the start of each wash: check pockets, unroll sleeves, turn clothes the right way and unroll socks. This presumably means that depending on how much time you’re prepared to spend doing these things (potentially infinite, since it doesn’t specify you’re not allowed to roll the sleeves back up again in between unrolls, and there’s no limit to how many times you can check a pocket) you can really mess with the results of the equation.

You may have noticed, if you now compare this to our brilliantly mangled equation in the infographic, that what they’ve managed to do here is, in an attempt to indicate that $L$ is given by $p \times f$, have put it in the equation as $L(p \times f)$ – they’ve used the parentheses as ACTUAL PARENTHESES, thus entirely ruining the meaning of the equation. They also appear to rename the variables at will, replacing $P$ with $PA$, possibly to avoid confusion with little $p$ but in practise creating more confusion. If you feel sick, feel free to stop reading and take a break.

In the full report, it transpires they’ve actually put in a fair bit of effort – researching the psychology of why socks are likely to go missing, and at one point referencing this lovely Mathematics Today article from 1996 on Murphy’s Law and sock loss (PDF) – essentially, each time you lose a sock from a collection of distinct pairs, it’s much more likely to be one from a complete pair than one of the already odd socks made by a previous sock loss.

This is a pleasing bit of pre-existing literature (and possibly the only bit of pre-existing literature on the topic) for them to reference, and it shows me the scientists behind this have at least put in the effort. It’s a dire warning to anyone who’s ever approached to come up with a ‘formula for X’ – and I occasionally do get asked, as a medium-profile human with maths inclinations, but have so far just about managed to resist the urge – that whatever you come up with, even if you put in some real effort to make it good, will likely be wholesale mangled by the PR/typesetting/graphic designers whose job isn’t to do maths, and nobody will check it’s right at the other end, so you’ll be left looking like a right odd sock.

Of course, the real way to avoid all of these problems is just by buying all your socks at once and have every single pair be identical, so if you lose any even number of socks you still have all complete pairs you can wear. Or alternatively, not worry about wearing non-matching socks. Or spend hundreds of pounds on a swanky washing machine with a hole in the door. Or, get a power drill and…

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