Mathematician. Reader. Fiftysomething. Cruciverbalist. Not very good at thinking of witty things to put in short bios.
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2026-08-02T14:43:37Z Event JSON
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Last Notes npub1xeq9nj0ss36mr3ynzzym9xfcgzczcxsvju6sc4rf557q5r0utcfsydnmfq gjm A bit of pedantry: surely it's not true that the 2-adics "can go on infinitely in both directions". They can go on infinitely _to the left_ and any arbitrary finite amount to the right. Just as ordinary real numbers written in base 2 can go on infinitely to the right and any arbitrary finite amount to the left. npub1xeq9nj0ss36mr3ynzzym9xfcgzczcxsvju6sc4rf557q5r0utcfsydnmfq gjm I want to see the followup from Roger Penrose and Julian Jaynes about how this means the Norse gods may have been conscious even though the ancient Greek gods weren't. npub1xeq9nj0ss36mr3ynzzym9xfcgzczcxsvju6sc4rf557q5r0utcfsydnmfq gjm My reading of that thread is that this isn't a _nicer counterexample_ but a _nicer description of the same counterexample_. Have I misunderstood? npub1xeq9nj0ss36mr3ynzzym9xfcgzczcxsvju6sc4rf557q5r0utcfsydnmfq gjm Israel's treatment of the West Bank is shockingly evil, but I think calling human beings "brutish animals without hearts or souls" is rather how we got into this sort of situation in the first place. I bet that's exactly how a lot of Israelis talk about the Palestinians who are fighting them. npub1xeq9nj0ss36mr3ynzzym9xfcgzczcxsvju6sc4rf557q5r0utcfsydnmfq gjm Superficial observation that might help somehow. (I suspect from Oscar's remark that he has made the same observation.) npub1xeq9nj0ss36mr3ynzzym9xfcgzczcxsvju6sc4rf557q5r0utcfsydnmfq gjm And, looking more carefully, my extrapolations do seem like they're closer to one another and to the value claimed on that page than they are to 41√3/168. npub1xeq9nj0ss36mr3ynzzym9xfcgzczcxsvju6sc4rf557q5r0utcfsydnmfq gjm A commenter on math.stackexchange.com at https://math.stackexchange.com/questions/4047421/what-is-the-average-distance-between-two-randomly-chosen-points-on-a-sierpi%C5%84ski links to a programming-contest site and claims that it mentions someone who's found an efficient way to compute this value. For me the link goes somewhere uninformative but archive.org has what I think the link was to. The page is in Korean so I am relying on machine translation. I think the mathematician mentioned on that page may possibly be fictional. npub1xeq9nj0ss36mr3ynzzym9xfcgzczcxsvju6sc4rf557q5r0utcfsydnmfq gjm Some numerology: npub1xeq9nj0ss36mr3ynzzym9xfcgzczcxsvju6sc4rf557q5r0utcfsydnmfq gjm This may well be an important and very correct and necessary book, but I really really dislike the title. npub1xeq9nj0ss36mr3ynzzym9xfcgzczcxsvju6sc4rf557q5r0utcfsydnmfq gjm Au contraire, it's definitely rouge. npub1xeq9nj0ss36mr3ynzzym9xfcgzczcxsvju6sc4rf557q5r0utcfsydnmfq gjm Are you sure about your Juliuses and your Scaligers? npub1xeq9nj0ss36mr3ynzzym9xfcgzczcxsvju6sc4rf557q5r0utcfsydnmfq gjm I suspect DLL's comment is a deliberate reference to this, but in case (1) it isn't or (2) others didn't notice, Raymond Smullyan wrote a whole book with this premise: https://en.wikipedia.org/wiki/To_Mock_a_Mockingbird npub1xeq9nj0ss36mr3ynzzym9xfcgzczcxsvju6sc4rf557q5r0utcfsydnmfq gjm By "fairly small" I meant on the order of 10^-10, which is the sort of thing I would expect to be fairly easily achievable in multiple ways by things looking like linear combinations of spherical shells. npub1xeq9nj0ss36mr3ynzzym9xfcgzczcxsvju6sc4rf557q5r0utcfsydnmfq gjm Note that the gravitational field of _any_ spherically-symmetrical thing is the same (up to a scaling of the total mass) _everywhere_ outside the sphere containing it. So it doesn't particularly matter whether the sample points are all on a single sphere. npub1xeq9nj0ss36mr3ynzzym9xfcgzczcxsvju6sc4rf557q5r0utcfsydnmfq gjm Have you looked to see what the almost-nullspace looks like? That is, what not-very-short vectors are mapped almost-to-zero? Or, to put it differently: your empirical finding shows that some distributions of mass have almost the same effect on your 83 red dots as others; what are they? npub1xeq9nj0ss36mr3ynzzym9xfcgzczcxsvju6sc4rf557q5r0utcfsydnmfq gjm It's too bad it can't be A000001. Though it wouldn't by any means be the first known-to-be-finite OEIS sequence; for instance A100000 is another. npub1xeq9nj0ss36mr3ynzzym9xfcgzczcxsvju6sc4rf557q5r0utcfsydnmfq gjm Some years ago, in the UK there was an election which the Liberal Democrat candidate was expected to win, with the Conservative candidate a close second. So the Conservatives got someone to run as a "Literal Democrat", he picked up a bunch of votes from people who didn't read carefully, and the Conservatives won. (The election regulations got changed after that so we didn't get the otherwise-inevitable deluge of "Conversatives" and "Literal Democrats" fighting to see who could confuse more voters.) npub1xeq9nj0ss36mr3ynzzym9xfcgzczcxsvju6sc4rf557q5r0utcfsydnmfq gjm By a curious coincidence, RFK Jr. _is_ an evil troll whose actions are likely to make some children sneeze non-stop until they drop dead, or at least something in the same conceptual vicinity. npub1xeq9nj0ss36mr3ynzzym9xfcgzczcxsvju6sc4rf557q5r0utcfsydnmfq gjm I hope they made it not too difficult for people to leave early. I'm going to guess you weren't the only ones. npub1xeq9nj0ss36mr3ynzzym9xfcgzczcxsvju6sc4rf557q5r0utcfsydnmfq gjm Good luck! (I like Tavener but I don't think I would cope well with 8 hours of one Tavener piece at a stretch.) npub1xeq9nj0ss36mr3ynzzym9xfcgzczcxsvju6sc4rf557q5r0utcfsydnmfq gjm Pedantic note: I think you mean not "The Protecting Veil", a famous Tavener piece but only ~45 minutes long, but "The Veil of the Temple", a newer piece by the same composer that is, indeed, 8 hours long. npub1xeq9nj0ss36mr3ynzzym9xfcgzczcxsvju6sc4rf557q5r0utcfsydnmfq gjm This is a slightly atypical case because usually when something's named after X it's because someone else discovered the thing first and then X wrote about it later[1], whereas in this case IIUC Moessner really did get there first but didn't _prove_ it. npub1xeq9nj0ss36mr3ynzzym9xfcgzczcxsvju6sc4rf557q5r0utcfsydnmfq gjm That paper also contains the line "the d-ism of Leibniz overtook the dotage of Newton" which is rather magnificent. Knuth puts it in quotes but doesn't say who it's from; it seems to be Charles Babbage, though his wording was a little different. npub1xeq9nj0ss36mr3ynzzym9xfcgzczcxsvju6sc4rf557q5r0utcfsydnmfq gjm Whether or not _that_ was a joke, there's something very appropriate about your photo showing Aristote's Fragme Sele. npub1xeq9nj0ss36mr3ynzzym9xfcgzczcxsvju6sc4rf557q5r0utcfsydnmfq gjm You don't have to expend time or money getting to and from the movie theatre. You have comfier seating. If you have friends or family, you can all watch at once for the same price. You are much less likely to catch whatever infectious diseases may be going around.
