# Articles by Tom Hockenhull

Tom is a PhD student studying a way of telling apart knotted pieces of string, and its relationship with other mathematical objects called ‘manifolds’.
@nocashvalue     wwwf.imperial.ac.uk/~th2109/    + More articles by Tom

• ### Modelling in a heartbeat

Learn how to model your heart one beat at a time ❤️
• ### Math Blaster

Belgin plays a classic mathsy game from her childhood...in 16-bit graphics! Here's her review...
• ### Why Knot?

You can un-knot a knot, by cutting it not?
• ### Surname Extinction

Why do surnames die out? We take a look at the Galton-Watson process for modelling the extinction of surnames to answer the question: 'When will we all be Smiths?'
• ### Crossnumber winners, Issue 06

Did you solve it?
• ### Well, well, well…

A fiendish puzzle for you to 'pour' over...
• ### The mathematical con artist

Some summations seem strangely slippery...
• ### Maths and music, together in harmony

Uniting the teaching of mathematics and music can benefit pupils greatly in both areas.
• ### Review of the year 2017

What have we been up to this year?
• ### Solution to Christmas conundrum #4

... and the winners
• ### Christmas conundrum #4

Can you solve four puzzles to reveal the hidden message?
• ### Review of The Element in the Room

Reviewing this week's conundrum prize... science-y stuff staring you in the face!
• ### Christmas conundrum #3

Try our nonograms! And remember, not all puzzles have a unique solution...
• ### The science behind Santa Claus

Christmas is coming, and Santa will soon begin his journey. We analyse the science and maths behind his trip.
• ### Christmas conundrum #2

Solve this and you could be the lucky winner of a signed copy of The Indisputable Existence of Santa Claus
• ### Carnival of mathematics 152

We round up some of the last month's top mathematical posts from around the internet
• ### Christmas conundrum #1

Solve this and you could be the lucky winner of a Chalkdust T-shirt
• ### Chalkdust’s Christmas conundrums

As the festive season strikes again, we'll be dishing out more fiendish puzzles – this time with prizes!
• ### Review of The Maths Behind by Colin Beveridge

Should you ask Santa for 'Ice Col' Beveridge's encyclopedic tome this festive period?
• ### MathsJam 2017

Chalkdust descends upon the UK's largest pop maths gathering and tells you what you missed
• ### Beghilos

When you get tired of using your calculator for numbers, why not use it for words?
• ### Dispersion on the dark side of the moon

Maths has strong connections to art and music, but what about to both at the same time?
• ### Closing the first Black Mathematician Month

Reflecting on what we've learnt over the past few weeks.
• ### In conversation with Vernon Morris

The co-author of a recent paper on diversity in professional STEM societies talks about access to science.
• ### In conversation with Talitha Washington

Meet Talitha Washington, an activist, mathematician, and professor
• ### My mathematical trajectory

Stories and lessons on diversity in mathematics from a globe-trotting number theorist.
• ### In conversation with Jonathan Farley

We spoke with Jonathan Farley about his research and experiences as a black mathematician.
• ### In conversation with Tanniemola Liverpool

As part of Black Mathematician Month, we spoke to the Bristol University professor about access schemes and the importance of mentors.
• ### Read Issue 06 now!

Cardioids in coffee cups, counting with three fingers, and breakfast at Villani's.Plus the return of all your favourite fun pages.
• ### Prize crossnumber, Issue 06

Win £100 of Maths Gear goodies by solving our famously fiendish crossnumber
• ### In conversation with Cédric Villani

We feel underdressed for Breakfast at Villani's

• ### Cardioids in coffee cups

Staring at your coffee, you wonder whether the light reflecting in cup really is a cardioid curve...
• ### Mathematics for the three-fingered mathematician

Robert J Low flips one upside down.
• ### Comic: The Inverse Homotopy, part 5

Part 5 of our mathematical comic's adventure
• ### The mathematics of Maryam Mirzakhani

We take a proper look at her mathematical accomplishments
• ### Which mathematical software are you?

"R" you a Matlab or a Python? Fortran or Mathematica? Find out which package suits you best.
• ### Top Ten: Geometry instruments

The definitive chart of the best tools
• ### Biography of Sophie Bryant

A biography of Sophie Bryant
• ### What’s hot and what’s not, Issue 06

Mathematical fashion advice for an ever-changing world
• ### Top ten vote issue 06

Vote for your favourite mathematical celebration day
• ### Geographic profiling

Murder, maths, malaria and mammals
• ### Roots: Blaise Pascal

Blaise Pascal was driven to begin the mechanisation of mathematics by his father's struggles with an accounts book in 17th century France.
• ### On the cover: Euclidean Egg III

Euclidean Egg III makes the cover of issue 06!
• ### Pretty pictures in the complex plane

Contemplate the beauty of the Julia and Mandelbrot sets and an elegant mathematical explanation of them
• ### Page 3 model: Crowd control

Modelling a Saturday afternoon on Oxford Street
• ### How to make: a hyperbolic plane

A great way to waste a lot of paper
• ### Pretend numbers

20 questions, the axiom of choice and colouring sequences.
• ### Four things you didn’t notice in Issue 05

How many did you spot?
• ### The kind of problems black mathematicians wish didn’t need solving

Stories that illustrate the barriers that black mathematicians have faced in recent history.
• ### Why do Afro-Caribbean pupils underachieve in education?

Data scientist Jonny Brooks-Bartlett gives his views as part of Black Mathematician Month.
• ### In conversation with Olubunmi Abidemi Fadipe-Joseph

Meet Olubunmi Abidemi Fadipe-Joseph, an active promoter for women in mathematics from Nigeria
• ### You don’t need permission to be a great mathematician!

Nira Chamberlain, one of the UK's top 100 scientists, shares his experiences as a black mathematician.
• ### Star polynomials

Natalya Silcott introduces us to star polynomials!
• ### In conversation with Nazar Miheisi

Our first interview celebrating Black Mathematician Month
• ### October is Black Mathematician Month

Promoting black mathematicians, and talking about building a more representative mathematical community.
• ### Chalkdust Issue 06 coming 19 October

Free launch party, 7.15pm. Come along!
• ### Between a square rock and a hard pentagon: fractional polygons

A polygon with four and a half sides?!
• ### The mathematics of brewing

While drinking beer in your favourite pub, have you ever wondered how it is produced? Find here some of the science and mathematics behind brewing.
• ### Seeing double

Take a ball, divide it into parts, glue them back and get two identical copies of your ball!
• ### Tupper’s self-referential formula

A hideous equation that hides beautiful images, and much (much) more besides...
• ### Four ways Photoshop encourages thinking mathematically

How processes used in image editing are related to mathematics!
• ### Creating hot ice

We created hot ice from scratch, a solution that remains liquid even below its freezing point!
• ### Going once, going twice… game theory?

A quick look at how to get the most bang for your buck the next time you're in a bidding war
• ### Review: Mathematical T-shirt

A summer essential or an embarrassment risk on the streets of Ibiza?
• ### Winning the Chalkdust coin game

How to win a game when your expected score is 0

Did you win?
• ### How many quadratics factorise?

Write down a quadratic. What is the probability that it factorises? Paging Prof. Dirichet...
• ### Crossnumbers and cross products

A crossnumber clue takes us plunging headfirst towards projective geometry
• ### The mathematics of human migration

Human migration with mathematical models, data and a hands-on experiment!
• ### Cat among the pigeons

Some interesting observations with the pigeonhole principle

• ### Top 10 emoji for use in mathematics

We take a look at the top 10 emojis!
• ### Making your own papercupter

Next time you are finished using a paper cup, create your own papercupter!
• ### What’s your least favourite number?

Read about our least favourite numbers in this collection from issue 5!
• ### Football free-kicks… taken by Newton

Discover the mysteries behind the most spectacular free-kick ever scored and how Newton can help us to simulate it.
• ### Taking the (mathematically) perfect picture at the Leaning Tower Of Pisa

Finding the best picture at the Leaning Tower of Pisa is all about the maths rather than the pose!
• ### The croissant equation

Each time you eat a croissant you might be biting more than 500 layers of dough!
• ### Review of Elastic Numbers

We have a go at the puzzles in Daniel Griller's new book
• ### In conversation with Marcus du Sautoy

We chat to Marcus about science communication, teaching mathematics in schools, and how to make group theory sound sexy.
• ### Thinking outside the box

Negative polygons and other mathematical creations
• ### The pipe singularity

In the Aztec city of Atzlan, the scientist Remotep makes a revolutionary discovery
• ### Superegg

How optimising the space around a circular monument is related to supereggs
• ### Is it better to run or walk in the rain?

When you're caught in the rain without an umbrella... what is your best option?
• ### Why self-service machines give such awful change

Unexpected item in bagging areAAAARGGGHH here's 90p change in pennies
• ### Is it possible to reach absolute zero?

After 100 years, a key postulate of the third law of thermodynamics has been proven. We meet Lluis Masanes, one of the researchers responsible.
• ### Forget a new £1 coin, we need a £1.23 coin

Not the new coin we want, but the new coin we need
• ### Cutting my birthday cake

How to make the most slices from just a few cuts of cake
• ### Issue 05

New issue out now! Graphical linear algebra, slide rules and game theory in nature. Plus all your favourite fun pages.
• ### In conversation with Bernard Silverman

We chat to the chief scientific advisor to the Home Office about the role of scientists and mathematicians in politics
• ### Linear algebra… with diagrams

Rediscover linear algebra by playing with circuit diagrams
• ### Debugging insect dynamics

Explain the strange dynamics of certain insects using game theory
• ### Variations on Fermat: an agony in four fits

Fermat's Last Theorem with complex powers, wrapped in a story every mathematician can relate to
• ### Slide rules: the early calculators

When slide rules used to rule... find out why they still do
• ### The simplest difficult task

Factorisation is often used in cryptography. But there's something even simpler which turns out to be just as hard.
• ### Origami tesseract

Folding origami, building networks, making projections and multiple dimensions!
• ### Florence Nightingale, statistician

What is the real story behind the lady with the lamp?
• ### Roots: Mary Somerville

Mary Somerville fights against social mores to become one of the leading mathematicians of her time.
• ### Prize crossnumber, Issue 05

Win £100 of Maths Gear goodies by solving our famously fiendish crossnumber
• ### On the cover: dragon curves

Read more about the fire-breathing curves that appear on the cover of issue 05
• ### What’s hot and what’s not, Issue 05

Mathematical fashion advice for an ever-changing world
• ### Dear Dirichlet, Issue 05

Prof. Dirichlet tackles political arguments and werewolves in answering your personal problems
• ### Comic: The Inverse Homotopy, part 4

Part 4 of our mathematical comic's adventure
• ### Puzzles, Issue 05

Solve the puzzles that appeared in Issue 05.

• ### Which mathematical object are you?

Are you feeling ideal? In your prime? Discover your inner mathematical object (plus handy term explainer).
• ### How to make: a slide rule

Make calculations easy with this simple-to-make slide rule
• ### Top Ten: Parts of a circle

The definitive chart of the circle's greatest parts
• ### Top ten vote issue 05

Vote for your favourite geometry instrument
• ### Puzzle Solutions, Issue 05

The answers to the puzzles that appeared in issue 05
• ### Seven things you didn’t notice in Issue 04

How many did you spot?
• ### Chalkdust Issue 05 coming 7 March

Free launch party, 7.15pm. Come along! Free copies of Chalkdust, free pizza, and buy your own Chalkdust T-shirt.
• ### The digital sum of the products of twin primes is 8?

What connects the products of twin primes with something you learnt in primary school and the number 8?
• ### To share, or not to share

A tragic love story of shares and viral songs. To share, or not to share...

• ### Curiouser and curiouser!

Some surprising mathematical facts
• ### Two years of Chalkdust!

Here are some highlights of the first two years of Chalkdust!
• ### Crossnumber winners, issue 04

Are you a winner?
• ### The limit does not exist!

Lindsay Lohan is really good at L'Hôpital's rule.
• ### Is MEDUSA the new BODMAS?

Why the infamous acronym needs revising.
• ### Review: Mathematical socks

Can you wear them and be taken mathematically seriously?
• ### Chalkdust Review of the Year 2016

Before we say 'Goodbye' to 2016 let us highlight a few of the articles on the Chalkdust website.
• ### Advent Calendar: 24 December

It's the last day of the Chalkdust advent calendar, so there must be something very good behind today's door...

Behind today's door... a puzzle!
• ### The Indisputable Existence of Santa Claus – A review

Behind today's door... A book review!

Behind today's door... More fascinating facts!
• ### Christmaths carols II

Behind today's door... Another carol!
• ### Find your perfect partner

Find your perfect partner with this wonderful tree diagram!
• ### Christmas cracker joke III

Behind today's door... A joke!
• ### Dear Dirichlet Christmas special

Behind today's door... A quiz!
• ### The Chalkdust Christmas card

This year's Chalkdust puzzle Christmas card

Santa's sack of scientific surprises
• ### Which mathematician are you?

Behind today's door... a quiz!

Behind today's door... a puzzle!
• ### Christmas cracker joke II

This post was part of the Chalkdust 2016 Advent Calendar. Newton: “Are you going to the Fibonacci themed Christmas party?” Euler: “Yes! I heard it’s going to be as big as the two previous years put together.”
• ### Christmas cracker joke I

Behind today's door... a good joke!
• ### Binary magic card trick

Behind today's door... A binary magic card trick!
• ### Snowflake, the symbol of winter: different sizes, infinite shapes

Winter is coming!
• ### What should you get a mathematician for Christmas?

Behind today's door... The Chalkdust guide to Christmas presents

Behind today's door... a puzzle!
• ### Five gold rings

And on the fifth day, some rather Algebraic Golden Rings:
• ### Christmaths carols I

Behind today's door... a mathematical Christmas Carol

Santa's sack of scientific surprises

Behind the second door of the advent calendar, there is a puzzle
• ### The n days of Christmas

Get into the ChristMATHS spirit with the maths behind the popular Christmas carol!
• ### Catching criminals with maths

How crime science, and the maths it uses, is helping the police fight crime
• ### What’s your favourite set?

Here we have collected our favourite sets, from the Mandelbrot set to the Mahut-Isner set!
• ### Visualising mathematics with 3D printing

Using modern technology to understand geometry
• ### Feeling the love for Chalkdust T-shirts

The algebra will set your heart aflutter.
• ### The spider witch project

Constructing a spiderweb: in the spookiest and most horrific way possible!
• ### Hooke’s Monument

The Great Fire of London, a little-known polymath and a Monument...
• ### Killing by numbers: the mathematics of warfare

A blast from the past. Modelling battle grounds from ancient Greece.
• ### Top ten vote issue 04

Vote for your favourite part of a circle
• ### Issue 04

Our sparkly new edition, out now! Problem solving 101, proof by storytelling, plus the return of all your favourite fun pages.
• ### Problem solving 101

Never be stumped by a maths problem again, with this crash course from the ever-competent Stephen Muirhead

• ### Comic: The Inverse Homotopy, part 3

Part 3 of our mathematical comic's adventure
• ### Hedy Lamarr: Hollywood star and secret inventor

James Grime gets intimate with 'the most beautiful woman in the world' from the golden age of Hollywood
• ### The doodle theorem, and beyond…

Colin Wright juggles Euler, doodling and Millennium problems
• ### What’s hot and what’s not, Issue 04

Don't be left behind... more mathematical fashion advice
• ### Prime jewellery

Make your own treasures, guaranteed to be priceless on a future episode of Antiques Roadshow
• ### Solve our crossnumber

Win £100 of maths goodies in our fiendish crossnumber
• ### Puzzles, Issue 04

Solve the puzzles that appeared in Issue 04.
• ### Roots: Pythagoras of Samos

Pythagoras gave us so much more than a² + b² = c²
• ### Mathematics: queen of the arts?

Exploring the connection between maths and art.
• ### How to make: mathematical crochet

How to make mathematical crochet
• ### Top Ten: Colours of chalk

The definitive chart of chalk's greatest colours
• ### Page 3 model: Hallucinations

The geometry of psychedelic hallucinations
• ### Prize crossnumber, Issue 04

Can you solve it?
• ### Puzzle Solutions, Issue 04

Warning: Contains SPOILERS!
• ### Proof by storytelling

Sit in your favourite chair and do away with those tedious algebraic proofs

• ### The Buckingham π theorem and the atomic bomb

Diego Carranza tells you to stop worrying and dimensionally analyse the bomb
• ### In conversation with Andrea Bertozzi

We chat to Andrea about crime, maths and her fluid career
• ### Issue 04 launch quiz

Tuesday 11 October, 7.15pm. Come along! Featuring hundreds of free copies of Chalkdust, free pizza, and the chance to purchase a Chalkdust T-shirt.
• ### Man vs Maths

A review of Timothy Revell's new book, describing the hidden mathematics behind our world
• ### Why maps are wrong

If only the Earth were flat...
• ### The evolutionary arms race

Applying game theory to evolution
• ### Hairy balls, cyclones and computer graphics

What can a 100-year-old result in topology say about weather and computers?
• ### Donald in Mathmagic Land

Donald Duck learns that there is “a lot more to mathematics than two-times-two”.
• ### Maths at EMF camp

Exploring the maths on offer at this year's UK hacker festival.
• ### Why I hate an empty bus stop

How the queue size tells you when the next bus is coming
• ### Mathematicians and their Gods

Believe it or not: Mathematics and Theology can coexist
• ### Crossnumber winners, issue 03

Are you a winner?
• ### Switching sides in a matrix equation

Looking for a neat description of this useful matrix part-inverse

Were you a Choco Leibniz or a Fig Newton?

Can you solve these puzzles about differentiation and integration?
• ### Changing the status quo

Difficulties in designing a voting system for referenda
• ### Tennis maths: how long should a deuce point last?

Using Markov chains to calculate some interesting tennis stats!
• ### Constructing a sphere with 455 cups

Paper cups do not follow a hexagonal pattern and the cones do not meet at a single point, but they do make a gigantic sphere
• ### Mini crossnumber

All the fun of our prize crossnumber, just smaller and without a prize
• ### The Housekeeper and the Professor

Memory and maths in the modern world
• ### Stopping distances in the Highway Code are wrong

An easy equation to remember for your driving theory test, with dangerous consequences
• ### A brief history of gravitational waves

The discovery of gravitational waves offers a new way of looking at the universe. Who knows what we will discover?
• ### How many cups does it take to make a sphere?

The Chalkdust team set you a challenge, for which the prize is a £25 Amazon voucher...
• ### Names for large numbers

Extending the million, billion, trillion system to much, much bigger numbers
• ### Cracking the Guess Who? board game

Maths and Decision Theory to be the best at playing Guess Who?
• ### The mathematics of tea-making

When-to-add-milk confusion and other related matters
• ### Hunting for polydivisibles

The search for polydivisible numbers in different bases: how many can you find?
• ### Carnival of Mathematics 133

This month's round up of mathematical blog posts.
• ### Are we getting tired of Twitter?

Here is the reason why the golden era of Twitter is gone
• ### The wonders of mathematical crochet

Hyperbolic surfaces, Klein bottles and more

• ### Issue 03 launch quiz answers

How many did you get right?
• ### Issue 03 launch quiz

How many points could you have scored at our launch quiz?
• ### Puzzle Solutions, Issue 03

Warning: Contains SPOILERS!
• ### How to make: a hexaflexagon

Make an amazing three faced hexagon
• ### Analogue computing: fun with differential equations

Solving differential equations instantaneously, using some electrical components and an oscilloscope
• ### Top Ten vote: Colours of chalk

Vote for your favourite colour of chalk for Issue 04: is it white, yellow, or the Post Office Tower?
• ### Roots: the legacy of Fibonacci

More than spirals and rabbits, Fibonacci gave us something much more fundamental.
• ### The Mathematical Games of Martin Gardner

The great contributions of the man who started popular mathematics
• ### What’s hot and what’s not, Issue 03

Maths is a fickle world. Stay à la mode with our guide to the latest trends.
• ### Puzzles, Issue 03

Solve the puzzles that appeared in Issue 03.
• ### Flexagon Templates

Print out and make a flexagon
• ### Page 3 model: Traffic flow

Ever been stuck in motorway traffic which seems to have no reason? A model for traffic flow explains why.
• ### Dear Dirichlet, Issue 03

Prof. Dirichlet tackles deaf colleagues and cold badgers.
• ### Prize crossnumber, Issue 03

Be in for a chance to win a £100 goody bag if you can solve our fiendish crossnumber
• ### Spherical Dendrite by Mark J Stock

The story behind Issue 3's cover artwork
• ### Read Issue 03 now!

Fractional calculus, counting divisors, whether voting can ever be fair and much more
• ### You can count on Dirichlet

Counting the divisors of an integer turns out to be a rather hard problem
• ### Horoscope, Issue 03

Find out what the future holds for you... or maybe just a box of scorpions.
• ### A mathematical view of voting systems

Why voting systems can never be fair
• ### Comic: The Inverse Homotopy, part 2

Part 2 of our mathematical comic's adventure
• ### Top Ten: Calculators

Are you a FX-82 or an FX-85 fan?
• ### Menace: the Machine Educable Noughts And Crosses Engine

Teaching a bunch of matchboxes how to play tic-tac-toe
• ### Fractional calculus: the calculus of witchcraft and wizardry

How can we differentiate a function 9¾ times?
• ### In conversation with Ian Stewart

We speak to one of Britain's most successful popularisers of maths
• ### Issue 03

Fractional calculus, counting divisors, whether voting can ever be fair and much more
• ### Fun with water bells

Explaining how surface tension makes water form surprising shapes
• ### Chalkdust Issue 3 coming soon! 14/03/16

Your first peek at our Spring issue

• ### Finding the edge of your images

How can we identify objects in photos, to diagnose cancer or predict the weather? Using gradients!
• ### The analytics of healthcare

Simple Statistics can help businesses make informed decisions
• ### How to tile a chessboard

Introducing polyominoes
• ### New largest prime number discovered!

Amaze your friends with our top facts about the new largest known prime number
• ### The Drake equation

Is there life on Mars? Or anywhere else?
• ### Victorian maths tricks with old money

Exploring mental arithmetic tricks in T. Martin's 1842 guide, 'Pounds, shillings and pence'
• ### Chalkdust review of the year 2015

Have you read the best of the blog?
• ### Christmas puzzles

Something for you to solve during the post-Christmas lull

• ### Crossnumber winners

Are you a winner?
• ### How to make: Christmas Special

Making gingerbread Platonic solids, Fröbel stars and Christmas flexagons
• ### What’s your favourite function? Part II

We have received loads of feedback from people telling us their favourite function
• ### 100 years with the Sierpinski triangle

Three ways to obtain and generalise a beautiful fractal
• ### Weekend at MathsJam

Chalkdust visits popular maths' biggest conference
• ### Klaus Roth

(1925 - 2015)

• ### Puzzle Solutions, Issue 02

These solutions relate to puzzles found in Issue 02 of the magazine.
• ### Our Favourite Functions: Part I

Because we love functions!
• ### How to kick a conversion

Where should you choose to take a conversion kick from?
• ### Somewhere over the rainbow

Some mathematical questions you might have wondered every time you look at one of those rainbows
• ### Issue 02

The joy of Jacobians, the perils of p-values, and a chat in the pub with Fields medallist Artur Avila
• ### How much will I win on the new National Lottery?

What difference will an extra 10 balls make?
• ### Things to make

Platonic shapes from tube maps, flexagons, and more mathematical craft

• ### Top Ten: Mathematical symbols

It's time to reveal the Top Ten Symbols in Algebra!
• ### John Forbes Nash: the legacy

Exploring the legacy of John Nash (1928 – 2015)
• ### What’s hot and what’s not, Issue 02

We tell you what's popular in the world of maths, so you can get ahead of the curve!
• ### Comic: The Inverse Homotopy, part 1

Continue the journey of the Inverse Homotopy...
• ### Page 3 model: The Duckworth–Lewis method

Meet the Duckworth-Lewis method, 23, from Lancashire
• ### Fermat Point by Suman Vaze

The maths behind Issue 02's cover
• ### In conversation with Artur Avila

Chatting with a Fields Medallist in a Leicester Square pub
• ### Read Issue 02 now!

The joy of Jacobians | Fields Medallist Artur Avila | Fractograms | Nash's legacy | The perils of p-values
• ### £100 Prize Crossnumber, Issue 02

Win £100 in our famous original crossnumber
• ### Puzzles, Issue 02

These puzzles appeared in Issue 02 of the magazine.
• ### The joys of the Jacobian

Robert Smith? tells us how his favourite matrix saves lives

Why does warm water freeze faster than cold water?
• ### Breaking out of the prisoner’s dilemma

What happens if you play the prisoners' dilemma against yourself?
• ### The perils of p-values

David Colquhoun explains why more discoveries are false than you thought
• ### Roots: All things being equal

The story of how we got the equals sign
• ### Fractograms

Hugh Duncan explores the hidden patterns of fractions
• ### Why is it so hard to pull two phone books apart?

Take two phone books and interleave all their pages one by one. Now try and pull them apart by their spines. Impossible, right?
• ### Chalkdust Issue 2 coming soon! 06/10/15

Find out what's going to be inside
• ### Number Rumbler–a new fun maths game!

Maths on Toast is a charity that aims to challenge and change the public's perception of mathematics...
• ### Our Favourite Blogs

A selection of our favourite mathematical blogs

• ### Can you solve these puzzles?

While we work on issue 2
• ### Time turns backwards at the Spark Festival

The extreme weirdness of slow viscous flows, and why borrowers shouldn't use doggy paddle.
• ### Introducing the Cuboku

Can you solve our 3D Sudoku puzzles?
• ### Is there a perfect maths font?

Let's print your thesis in Comic Sans
• ### Do you have too many or too few friends?

Do we have a natural limitation on the number of friends that we have?

• ### Crossnumber winners

Are you a winner?
• ### Thoughts on the crossnumber

Did you use meta-logic to solve the crossnumber?
• ### Answers to puzzles on square grids

These are the answers to the puzzles which appeared in this blog post.
• ### How to make: Platonic solids from tube maps

Impress your friends! As presented in our Talkdust show.
• ### Puzzles on square grids

How to make Sudoku more interesting
• ### Pandigital square numbers

Why are there none in base 13?
• ### Puzzles, Issue 01

These puzzles appeared in Issue 01 of the magazine.
• ### Will the Universe actually end in a big rip?

What the Guardian got wrong...
• ### Ace

How tennis players spin and slice their serves
• ### What’s your favourite number?

Favourite numbers for many are linked to birthdays or anniversaries, but here is our take on the question
• ### Maths for money: The Longitude Prize

When people do science for money…
• ### What makes a good puzzle?

If you enjoyed Hannah's sweets then you'll love these...
• ### Can we do good more effectively?

Choosing which charity we donate money to shouldn't be an entirely emotional decision.
• ### Review of Birth of a Theorem

Cédric Villani’s Birth of a Theorem tells the story of a mathematical theorem
• ### The statistics of a squeaky bum

Does form going into the play-offs predict your success?
• ### For the love of puzzles

Pub ✕ maths = ?
• ### Politics: a tweeting glance

What does Twitter have to do with politics?
• ### Introducing the Chalkdust blog

We have some fantastic blog articles, and this is how we plan to publish them.
• ### Optimal Pac-Man

Ghostbusting with graph theory
• ### Reinventing 2D

What a difference a matrix makes

How similar are you to your friends?

• ### Write for us

Share your favourite maths with the world
• ### Issue 01

The perfect game of Pac-Man, the maths of wormholes, and Anna talking at Hannah Fry
• ### Page 3 model: When zombies attack

Every issue we feature another great model on page 3 of our magazine. This time we look at what to do when zombies attack.
• ### Optimal Pac-Man

Matthew Scroggs spends too much time beating this arcade classic.
• ### Reinventing 2D: What a difference a matrix makes

How derivatives of matrices are being used in your day-to-day lives

• ### What’s hot and what’s not, Issue 01

Be the envy of your friends with our guide to what's hot in maths right now
• ### Top Ten: Mathematicians’ haircuts

The undisputed Top Ten Mathematicians' Haircuts!

Here is a very exciting way to measure how similar is your music playlist between your friends, or how similar are your Facebook contacts.
• ### In conversation with Hannah Fry

On the mathematics of love, communicating maths to the public, and women in maths.
• ### A Fields Medal at UCL: Klaus Roth

Klaus Roth and his work

• ### The Symposium of the Muses

The resultant art is the outcome and purpose that elevates and distinguishes the science.
• ### Puzzle solutions, Issue 01

These solutions relate to puzzles found in Issue 01 of the magazine.
• ### Interstellar travel: the mathematics of wormholes

Matthew Wright looks at wormholes in sci-fi
• ### Interstellar travel

Investigate the mathematics of wormholes