Why is there no equation for the perimeter of an ellipse‽

From Standup Mathematician. Applications for paid internships at Jane Street are open! https://www.janestreet.com/join-jane-street/internships/ A Podcast of Unnecessary Detail is out now: https://festivalofthespokennerd.com/podcast/ Come for the Unnecessary Detail, stay for the A Podcast Of. These are my approximation equations: perimeter ≈ π[53a/3 + 717b/35 – √(269a^2 + 667ab + 371b^2)] perimeter ≈ π(6a/5 + 3b/4) If…

Landmark Numbers and Bad Number Analogies

From Standup Mathematician. You can pre-order Tim’s book How to Make the World Add Up now! https://mathsgear.co.uk/products/how-to-make-the-world-add-up-signed-hardback Watch Tim Harford talk about the Stork-Baby correlation on Numberphile: https://www.youtube.com/watch?v=-n-d1ApBTFw Here is the current Landmark Number recommended toolkit (yours may differ). – population of the country you live in – ‘people days’ per year in your countries…

What is the biggest tangent of a prime?

From Standup Mathematician. What is your Mega-Favourite Number? The playlist of #MegaFavNumbers videos is here: https://www.youtube.com/watch?v=R2eQVqdUQLI&list=PLar4u0v66vIodqt3KSZPsYyuULD5meoAo If you make a video about a number bigger than 1,000,000 use the hashtag #MegaFavNumbers and we’ll add it to the playlist! Here is my current mega-favourite number: 1,169,809,367,327,212,570,704,813,632,106,852,886,389,036,911 This is the OEIS page for A249836: Numbers n for…

Does “land area” assume a country is perfectly flat?

From Standup Mathematician. You can listen to the A Problem Squared podcast here (and everywhere else). Please do! https://aproblemsquared.libsyn.com/ Huge thanks to Dr Laura Graham! Everything they did is on github: https://github.com/laurajanegraham/surface_area/blob/master/surface_area.md All about Laura: https://laurajanegraham.github.io/ Prof Alasdair Rae was also big help and sent me their slides. http://bit.ly/measurelandarea This is that video: https://www.youtube.com/watch?v=pDYkiK90WCM All…

Ellipsoids and The Bizarre Behaviour of Rotating Bodies

From Standup Mathematician. Derek’s video: The Bizarre Behavior of Rotating Bodies, Explained https://www.youtube.com/watch?v=1VPfZ_XzisU Based on this amazing footage: Dancing T-handle in zero-g https://www.youtube.com/watch?v=1n-HMSCDYtM Terence Tao’s original answer, with update. https://mathoverflow.net/questions/81960/the-dzhanibekov-effect-an-exercise-in-mechanics-or-fiction-explain-mathemat Support me on Patreon and I can make more video like this! https://www.patreon.com/standupmaths We are sat so close because we filmed this in the “before…

Complex Fibonacci Numbers?

From Standup Mathematician. Huge thanks to Jane Street! https://www.janestreet.com/join-jane-street/ Check out Ben Sparks’s GeoGebra files. Binet formula 2D complex output: https://www.geogebra.org/m/twvvzpga 3D imaginary output of Binet formula: https://www.geogebra.org/m/z6dy9cj5 3D plot of absolute output of Binet formula: https://www.geogebra.org/m/pb7hmxyd My four-part series on Numberphile videos about Fibonacci Numbers (from 2014) starts here. https://www.youtube.com/watch?v=D8ntDpBm6Ok Here is me going…

The Stack Folding Challenge

From Standup Mathematician. AHGD / BCFE AHBG / DECF The "Stack Folding Challenge" is to fold the two lay-outs I show in the video. But the MPMP meta-puzzle is to work out how many different Stack Folding Challenges are possible. That is to say: how many ways can you fold such a piece of paper…

Are Matt and James anti-psychic?

From Standup Mathematician. Yes, technically we’re "NAND psychic". Want to own Matt’s red/black sign, signed by him and James? It’s being auctioned for charity: https://www.ebay.co.uk/itm/362997607146 James’s Singing Banana channel is over here: https://www.youtube.com/user/singingbanana Here is our previous collaboration: "The Difference of Two Squares" https://www.youtube.com/watch?v=LkIK8f4yvOU Want to watch the full unedited footage of us being anti-psychic?…

The 1890 US Census and the history of punchcard computing [feat. Grant of 3blue1brown fame]

From Standup Mathematician. Thanks to Grant Sanderson (of 3blue1brown fame) for joining me on a fun day out! Best double-check you are definitely subscribed to their channel: https://www.youtube.com/3blue1brown If you are ever in the Bay Area you should totally check out the Computer History Museum. https://computerhistory.org/ Bubbles Whiting – Using Punch Cards – Hollerith and…

The Parker Machine: it’s 80% accurate.

From Standup Mathematician. Check out the full lecture on the Royal Institution YouTube channel. https://www.youtube.com/watch?v=_q4DrUHKC0Q Ri Christmas Lectures thanks to: The BBC – https://www.bbc.co.uk/programmes/m000crbc The Royal Institution – https://www.rigb.org/christmas-lectures/2019-secrets-and-lies Windfall Films – http://www.windfallfilms.com/show/1054/royal-institution-christmas-lectures.aspx Directed by David Coleman, produced by Laura Voak. Bonus footage filmed and edited by Matt Parker CORRECTIONS – Nothing yet. Let me…