Linkage

Congratulations to Johan Håstad, this year’s Knuth Prize winner! His contributions include important work on circuit lower bounds, interactive proof systems, and inapproximability.

Origami wrapping paper. So that after you unwrap your gift you can have fun folding something else.

We have finally figured out how to snap spaghetti into two pieces (G+, see also). The trick is to twist it as you bend it.

European parliamentarian Julia Reda wrote a blog post warning of a repeat attempt by the EU to force filtering mechanisms into all internet services, with a vote scheduled for September 12. Her opponents used the same mechannisms to censor her post from Google (G+, via).

These students are making science easier to understand on Wikipedia, one article at a time (G+).

400,000 scientists all over the world have been published in fake journals. It’s clear that this is not just a few bad apples or a few badly-advised new researchers. This corrupt parallel-publication system is thriving, in part as the result of misguided attempts to manage researcher productivity through bibliometrics.

xkcd: Edgelord (G+). Who can resist a silly joke about graph theorists? Not me.

Antipodal points. Another tennis ball theorem from +Numberphile, maybe a little easier to prove than the more famous one.

The war over supercooled water (G+, via). Beyond telling us how much still remains mysterious about something as seemingly simple and everyday as water, this story has an interesting moral to tell us about the importance of openly available software for reproducing the results of experimental simulations.

Recreational mathematics for fun, sanity, and sometimes even papers. There are some amusing mathematical puzzles in this post involving quilting bees and card shuffling, but mostly it’s about how recreational mathematics can become the gateway drug to serious mathematics, and can continue to inspire even after the mathematics becomes serious.

Draw a chessboard in perspective view, using straightedge only (via). Joel Hamkins shares some basic tricks in perspective drawing.

Road interchanges with minimal numbers of bridges (G+, via). With some debatable assumptions the problem of optimal interchange design can be reduced to computing the genus of the complete tripartite graph \(K_{n,n,1}\).

The duties of a mathematician (G+). Mochizuki follower Ivan Fesenko says mathematicians are duty-bound to “study each new groundbreaking theory or proof in one’s general area”. John Baez disagrees.