Posted in dome.

There was a Fields Medallist named Dan Quillen, after whom are named several things in topics I’ve never head of. Other than Quillen, so far as I can tell, the only mathematical eponyms beginning with Q relate to Willard Van Ormine Quine. I know him from Godel, Escher, Bach, where

Read More →
Posted in dome.

“Lightly grease a 20x20cm baking tin with butter and spoon in the mixture. Press into the corners with the back of a spoon so the mixture is flat and score into 12 squares.” - BBC Good Food flapjack recipe by user nicolajlittle Hang on a minute - I thought, mid-baking.

Read More →
Posted in dome.

Today’s entry in the Dictionary of Mathematical Eponymy is, by some distance, the entry that’s been most useful to me since I learned about it. (The Elo rating is probably in second place.) It’s also a unique entry in that I have next to no information about its originator. What

Read More →
Posted in dome.

We’ve just reached the halfway point of the Dictionary of Mathematical Eponymy project, and it’s time for a fairly famous one (and again, one I’ve been meaning to understand better). What is Noether’s Theorem? Emmy Noether has several theorems named for her, but the first (and probably most important) can

Read More →
Posted in dome.

After the Second World War, there was a boom in the study of transmitting encoded data. In likelihood, I imagine the boom started earlier, and the boom was more about the declassified publication of papers on this topic than about a sudden increase in productivity. This month’s mathematical hero, Jessie

Read More →
Posted in dome.

When I was about eight, my parents bought, as a Christmas gift for my brother and me, a “Jungle Gym”, plastic tubes and connectors that fit together to make whatever the imagination came up with, a sort of large-scale Meccano. My brother went out into the garden to build castles

Read More →
Posted in dome.

I am a big fan of polyhedra. I’ve raved elsewhere about the icosidodecahedron, and even something as dull as a cube is something I can get behind. And so, naturally, I wondered: is there a periodic table of polyhedra? And the answer is “not exactly”. But there’s something pretty close

Read More →
Posted in dome.

I… I… I… *Looks up Ito’s Lemma* *Reaches for bargepole, then doesn’t touch it.* I… I… I… Oh! It says here, there’s a thing called Ivory’s Theorem1! What is Ivory’s Theorem? Despite the main paper I could find about it calling it “the famous Ivory’s Theorem”, it was fairly tricky

Read More →
Posted in dome.

What are they? I thought, until I looked closely, that we had a Hoberman sphere in the children’s toybox. We don’t: we have something closely related to it, though. The Hoberman mechanism comprises a series of pairs of pivoted struts arranged end to end. Each pair looks a little like

Read More →
Posted in dome.

What are they? A Sophie Germain prime is a prime such that $2p+1$ is also prime - for example, 23 is a Sophie Germain prime since 47 is also prime. The largest known Sophie Germain prime has close to 400,000 digits; it is conjectured that there are infinitely many such

Read More →