Linkage

As Robert Fathauer points out (\(\mathbb{M}\)), the US “Star Ribbon” postage stamp depicts a star-shaped Möbius strip. If you slice the depicted ribbon lengthwise into two linked rings, its central white portion and outer red and blue portions, the inner part is again a Möbius strip while the outer part becomes doubly twisted and twice as long, with red on one side and blue on the other.

When its Japanese-American students were released from the concentration camps at the end of World War II, the University of Southern California refused to readmit them or even allow them to transfer their credits elsewhere (\(\mathbb{M}\)). Now, 80 years after the students were taken to the camps, USC is giving them posthumous honorary degrees.

Erik and Marty Demaine profiled for their work on squishing polyhedral surfaces flat (\(\mathbb{M}\)), in Quanta.

Russian government threatens to fine Wikipedia for not sticking to Russian propaganda in its reporting of the invasion of Ukraine (\(\mathbb{M}\), via, see also). Laughable, but the likely outcome appears to be that Wikipedia becomes blocked within Russia (as there is no possibility of complying with these demands) and Russia deepens its self-imposed isolation from civilized society.

Longstanding but still-active theoretical CS blog “Gödel’s Lost Letter and P=NP” makes a roundup of other still-active math and theoretical CS blogs (\(\mathbb{M}\)).

ACM makes its early publications, from 1951 to 2000, open access (\(\mathbb{M}\)). It’s not everything I’d want, but it’s a start…

You’re probably aware that Twitter has gradually joined Facebook and Instagram in deliberately walling itself off from the open web and making itself close-to-unusable by those of us without accounts. Manuel Grabowski writes that it’s also becoming significantly less usable even by those with accounts (\(\mathbb{M}\), via).

I’m sad to hear that algorithmist Gerhard Woeginger died recently, only aged 57 (\(\mathbb{M}\)). Much of his early work was in computational geometry (how we became coauthors), and I’ve posted on other papers of his, but some of my favorites include:

• Surveys on exact algorithms for hard problems, in Combinatorial Optimization — Eureka, You Shrink! and Disc. Appl. Math. 2007.

• Arranging lines with given numbers of crossings, in Theor. Comput. Sci. 2004.

• On river-crossing puzzles, in SIAM J. Disc. Math. 2010.

Christian Lawson-Perfect finds his perfect love match: someone who agrees on the best method of stacking eggs. Which raises “Kepler’s egg-packing problem”: what is that method, in an egg box of bounded width?

It’s the long-overdue Python2 apocalypse! (\(\mathbb{M}\)). I upgraded my laptop to MacOS 12.3.1 and somehow the upgrade nuked any old python2 executables I might have had in my path, so from now on everything has to be python3. Fortunately any of my old python2 scripts that I’ve tried to use so far have been very easy to fix (most complicated issue: installing Pillow to replace PIL). But I suspect that if I ever want to update and rebuild my old PyObjC-based apps, the changes will be more substantial.

David Roberts on fixing all the old broken links from StackExchange to the “Front for the Mathematics arXiv” (\(\mathbb{M}\)), a user interface veneer for arXiv that used to be available from UC Davis and has since gone away. You would think it would be a small matter of parsing the arXiv id in the link and replacing it with a current arXiv url for the same id, but…

You may have seen Science on cracking a Russian pay-for-coauthorship ring (\(\mathbb{M}\)). As the associated preprint arXiv:2112.13322 details, many reputable publishers had their journals caught up in publications of this ring. But it also points to suspicious patterns in MDPI journals, where several people from one country were both coauthors and editors of ring papers, and coauthorship slots were advertised as reserved for those editors.

Zugzwang describes a situation where moving first is a disadvantage, especially in games where it might usually be an advantage (\(\mathbb{M}\)). Quanta outlines four zugzwang puzzles in games ranging from chess to pizza-division. Solutions.

The ACM has given Carla Brodley their inaugural ACM Frances E. Allen Award for Outstanding Mentoring (\(\mathbb{M}\)), citing her work to improve the representation of women among students and faculty in her work as dean of computer science at Northeastern University, her founding of the Center for Inclusive Computing, which helps other institutions make similar improvements, and her leadership on the Computing Research Association Committee on Widening Participation.