11011110
About All posts
« Linus Pauling Commemorative Ceramic Mural Twenty questions with a random liar »

Linkage

Jan 15, 2025

  • My drunken theorem (\(\mathbb{M}\)). Bill Gasarch’s open problems column in memory of Luca Trevisan brings Lance Fortnow vague memories of drinking and deriving.

  • Origami black hole (\(\mathbb{M}\)). xkcd on what happens when you fold too many times.

  • Sophie Schmieg’s post-quantum crypto work acquires a crank who thinks he’s “created the first software only true random number generator”. Schmieg heads the ISE Crypto team at Google. It’s not clear to me exactly which blog post led to this, but her blog at Key Material has several interesting posts on post-quantum crypto and signature schemes.

  • Buddha cat dreams of Escher birds (\(\mathbb{M}\)).

    A carved yellow stone cat with a carved jacket and leaf hat sits in a buddha pose, front paws folded across its large round belly, in a garden with purple flowers, moss, bark chips, and some tufts of grass. In front of the cat is a large mossy square concrete paving tile patterned with Escher-like interlocked flying birds. A steel pole rises on the right edge of the image, next to the cat; its shadow cuts crisply across the paving tile like the gnomon of a sundial. Out of frame, the pole supports a bird feeder. Some small pebbles, smoothed round, sit at the cat's feet near the corner of the tile.

  • CodeParade tries to find another neighborly polyhedron (\(\mathbb{M}\)). The only two known ones are the tetrahedron and Szilassi polyhedron. They don’t succeed but they come surprisingly close.

  • The rectifiable rectangular peg problem (\(\mathbb{M}\)). New preprint by Tomohiro Asano and Yuichi Ike claims to prove the existence of a rectangle of arbitrary given aspect ratio in any rectifiable simple closed curve.

  • Recent encounters with atom-thin salami slicing (\(\mathbb{M}\), via), several case studies in bad-to-dishonest academic publishing uncovered by Reese Richardson.

  • Categorifiying Nicomacus of Gerasa’s equation (\(\mathbb{M}\)). A handwavy discussion of what the identity

    \[\sum_{k=1}^n k^3 = \left(\sum_{k=1}^n k\right)^2\]

    might really be counting, with nice pictures of 4-dimensional stacks of cannon balls.

  • Quanta on recent irrationality proofs for specific values of \(L\)-series (\(\mathbb{M}\)), along the lines of Apéry’s proof that \(\zeta(3)\) is irrational. Relatedly, @QuantaMagazine@mstdn.social hasn’t posted since June 2023, and @quanta_bot@social.platypush.tech hasn’t posted since November 2022. Is Quanta actually federated anywhere currently?

  • Rob Corless is annoyed at the bad reference metadata provided by Google Scholar. My go-to alternatives are MathSciNet/zbMATH for mathematics, DBLP for computer science, and a command-line invocation of curl for anything with a doi.

  • Mass exodus of German universities from X/twitter (\(\mathbb{M}\)).

  • Andrej Bauer tests Google NotebookLM, “your plastic pal who's fun to be with” “your personalized AI research assistant”. It did not go well. “The short summary is that the tool is exactly as good as an insolent incompetent science journalist.”

  • Claire Voisin: Mathematics as a private space – from the unveiling of conjectures to worldwide recognition (\(\mathbb{M}\)). Interesting interview with Voisin in the European Mathematical Society magazine, more about her life and philosophy than her mathematics.

  • New Calculator template brings interactivity to Wikipedia articles (\(\mathbb{M}\)). The template basically allows the creation of small forms that allow readers to specify some numbers as input and use a formula to generate an output. It’s even possible to simulate some simple algorithms step-by-step and expand the form after each step: see for instance an example of this for the Euclidean algorithm.

  • David Eppstein

Geometry, graphs, algorithms, and more