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David Eppstein
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I'm tempted to gloss this as "brains aren't fractal", but the article actually says the opposite: the authors think that brains do have a fractal structure, but a different one from the structure of crumpled paper.
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Jess Wade and Maryam Zaringhalam explain why you should, too.
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Sad news from Washington that Branko Grünbaum has died. I also heard today the sad news from New York that Ricky Pollack has died, but I don't know where to find a shareable link for that.
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Here's another piece from the Bridges 2018 art gallery, a scarf with a cellular automaton pattern by Elisabetta Matsumoto, +Henry Segerman, and Fabienne Serriere. This one looks to be Rule 150. The part that raises this above the level of "just another use of cellular automata to create decorative patterns", though, is that they carried out a search for an initial seed pattern that would return to itself, in reversed form, at the right length to form a nice Möbius-band scarf. So (except possibly for any unevenness in actually fabricating the join) the pattern is seamless.
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After Scott Aaronson called himself "not a physicist" despite recently winning a physics prize, Bill Gasarch posted this piece on just who should be called a physicist, a mathematician, or a computer scientist.

This one is always a dilemma for me. In academic circles I generally introduce myself as a computer scientist because that's what my PhD and my department are. Among Wikipedia editors I'm uniformly thought of as a mathematician (especially in the context of, what would a mathematician know about this other subject...) because I tend to edit more math than CS there. Socially it's a mix — I get the impression that when I'm introduced as a mathematician it gives people a more accurate idea of what I do than when I'm introduced as a computer scientist, but being introduced purely as a mathematician also makes me feel a bit of an imposter. The Wikipedia article about me (on which I have very little influence) says both, which more or less matches my own self-image.  I'm guessing others are similarly conflicted?

I saw something related today that amused me — I've been attending a conference at UCI for Alice Silverberg's 60th birthday, https://sites.google.com/site/silverberg2018/. In the opening talk, Kristin Lauter mentioned that she thinks of cryptographic number theory and number theoretic cryptography as being two different communities (for instance differing in use of arxiv vs iacr eprint or journals vs conferences) and that one of Alice's important contributions has been to work to bring them together. So whatever scale you choose to look at these disciplines, there are always going to be blurry lines, and people working to blur the lines more.
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This is a couple years old, but it's an amusing video, possibly useful for sharing with your students at the start of the term. In my experience many more students would benefit from going to faculty office hours than actually do. Some humor could help cut through their intimidation.
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A study finds no gendered differences in mean nor in variance of mathematical abilities in children young enough for sociological factors to not yet have kicked in. This is relevant for a recent fuss about the odd and disputed publication history of a paper by Ted Hill suggesting a mathematical explanation for how genetic differences in variance might be differentially advantageous for men vs women. It's a hot topic because these supposed differences have historically been used as an excuse for failure to improve gender ratios in mathematics. But if they don't exist, there's nothing to model and no basis for the excuse.

For some criticism of the actual mathematical-modeling content of the paper, see https://gowers.wordpress.com/2018/09/13/additional-thoughts-on-the-ted-hill-paper/ although in light of this study this seems to be in spherical cow territory to me.

What actually happened to Hill's paper is unclear enough to me (with people on different sides of the issue making contradictory claims — see links at the top of https://gowers.wordpress.com/2018/09/09/has-an-uncomfortable-truth-been-suppressed/ — and most evidence confidential) that I'm not going to express an opinion on what should have happened or who is at fault for something else happening.
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This artwork by Robert Bosch draws a picture of Königsberg and its seven bridges as an Eulerian graph on the points of a grid. It's only one of many many impressive and interesting pieces of mathematical art in the Bridges 2018 gallery, http://gallery.bridgesmathart.org/exhibitions/2018-bridges-conference
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The Wikipedia article on isosceles triangles has now reached Good Article status. Plenty of other similarly basic Wikipedia articles could still use similar improvement...
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‘Securing the Vote’: A Report From the National Academies of Sciences. "This elegant study focuses on the science of election security—without partisan bluster and without political preconceptions." https://www.lawfareblog.com/securing-vote-report-national-academies-sciences
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