7 ms·
Math and puzzle fans find magic in Martin Gardner's legacy
- ykonstant 2y agoAnother fantastic resource is Boris Kordemsky's book The Moscow Puzzles: https://www.amazon.com/Moscow-Puzzles-Mathematical-Recreations-Recreational/dp/0486270785 https://www.amazon.com/Moscow-Puzzles-Mathematical-Recreatio...
- I_complete_me 2y agoI think it was this book where I first saw the puzzle: Does New Year's Day fall more often on a Saturday or a Sunday? Such a simple puzzle with to (then) me such depth of knowledge to uncover the answer.
- bumbledraven 2y agoI don't see it there: https://archive.org/details/boris-a.-kordemsky-the-moscow-puzzles-1972/ https://archive.org/details/boris-a.-kordemsky-the-moscow-pu... Do you recall the solution? It seems like a tricky problem. No approach occurs to me aside from a brute force analysis of the 400 year Gregorian calendar cycle, accounting for the complete leap year rules (under which, e.g., 1900 was not a leap year but 2000 was).
- bumbledraven 2y agoIt turns out that New Year's Day is a bit more likely to fall on Sunday than Saturday. To confirm, here's a bit of simple JavaScript that checks a complete 400-year cycle. You can run it in your browser's console: const counts = Array(7).fill(0); for (let year = 2000; year < 2400; year++) { counts[new Date(year, 0, 1).getDay()]++; } console.log(`Number of Saturdays: ${counts[6]}; Number of Sundays: ${counts[0]}`); Output: Number of Saturdays: 56; Number of Sundays: 58 Note: getDay() returns 0 for Sunday and 6 for Saturday (https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Date/getDay https://developer.mozilla.org/en-US/docs/Web/JavaScript/Refe...).
- tromp 2y agoUnless you're considering a limited date range, it should fall equally often on both in the limit since neither 365 nor 366 (leap year) are multiples of 7.
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- madcaptenor 2y agoSo you’d think that, and it is approximately true. But the calendar repeats every 400 years (there are 97 leap years in 400, and 497 is a multiple of 7). And 400 isn’t a multiple of 7, so you can’t have it work out exactly.
- tromp 2y agoBut if the pair of (date, weekday) repeats every 400*7 years, then it still works out exactly?!
- bumbledraven 2y agoIn the Gregorian calendar, January 1 falls on a Saturday in any year that is a multiple of 400. (This follows from any correct day-of-the-week algorithm, such as https://firstsundaydoomsday.blogspot.com/2009/12/quick-start-guide.html https://firstsundaydoomsday.blogspot.com/2009/12/quick-start....) Since each 400-year cycle begins on the same day, rather than balancing out, any imbalances would actually accumulate. To check, see this 5-line brute-force calculation in JavaScript: https://news.ycombinator.com/item?id=42024474 https://news.ycombinator.com/item?id=42024474
- tromp 2y agoAh, the number of days in 400 years is 400 * 365 + 97 = (57*7+1) * (52*7+1) + (14*7-1) = 0 mod 7, so indeed it doesn't work out.
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- jeifneioka 2y agoDon't forget Raymond Smullyan.
- anthk 2y agoRecreational math and games boosted both computing and science. Unix was born to play games. And Curses was born for Rogue.
- chx 2y ago> Unix was born to play games Please correct me if I am wrong but I thought this was only the reason for the predecessor of it on the PDP-7: Thompson wanted Space Travel to run on the PDP-7 and the necessary boilerplate became a rudimentary OS. But porting this to the PDP-11 was not motivated by Space Travel -- or was it?
- musicale 2y agoI think "games" is one of the most accurate answers to the question "what are computers good for?" Though games are perhaps a subset of simulation in general (even if their simulation might be of an imaginary world rather than the real one.)
- beardyw 2y agoAll of his Scientific American articles were available as a CD I have. Not sure if they are online yet. As a youngster they were a source of wonder to me.
- glimshe 2y agoWhat is this CD? I like old compilations. Edit: found it, it's called "Martin Gardner s Mathematical Games: The Entire Collection of His Scientific American Columns"
- Jtsummers 2y agohttps://bookstore.ams.org/view?ProductCode=GARDNER-SET https://bookstore.ams.org/view?ProductCode=GARDNER-SET Cambridge University Press also started on a project to revise and re-release all of it but that stalled out, they published four books. https://www.cambridge.org/us/universitypress/subjects/mathematics/series/new-martin-gardner-mathematical-library https://www.cambridge.org/us/universitypress/subjects/mathem...
- smath 2y agoGardeners books and sci-am columns are an amazing resource to get kids and teens interested in math. In the present time, I find Simon Singh’s parallel.co.uk has been doing interesting work holding weekly math circles for kids - deftly engaging kids with mathematical ideas. I attend a circle with my 9 yo every Sunday.
- rahimnathwani 2y ago> Simon Singh’s parallel.co.uk Perhaps you mean https://parallel.org.uk/ https://parallel.org.uk/ ? I'm curious what the age range is? My son is 8.
- smath 2y agoYes that’s the one. I’d suggest sit through on of their parallel circles with your son- it’s a free 45 min casual live only session, on Sundays. And the schedule is by age group - listed on their website
- rahimnathwani 2y agoThanks. For my son's age, there's one this Sunday at 9am Pacific Time.
- pvg 2y agohttps://archive.is/hyF0u https://archive.is/hyF0u
- vundercind 2y agoHis annotated Alice in Wonderland is really nice, too.
- wpollock 2y agoI agree, although he missed one of the puns. In that day, even young children were taught latin. The speech with "O Mouse" comes from the lesson on conjugation which often used "am" (love): amo, amus, amat, amamus, amatis, amant. Having taken latin I recognized the joke. I always wished I could've written him about it.
- quesera 2y agoThe neglected Latin pedant in me can't not comment: 2nd person singular should be "amas". :)
- quuxplusone 2y agoCunningham's Law strikes again: sorry, but I doubt "O mouse" is a soundalike pun on "Amo, amas". Instead, the English (A mouse, of a mouse, to a mouse, a mouse, O mouse!) is simply the first five declensions in the traditional order: nominative, genitive, dative, accusative, vocative. (Mus, muris, muri, murem, mus.) As seen for example in this Latin schoolbook from 1891: [1] https://archive.org/details/bellumhelvetiumf00lowe/page/203/ https://archive.org/details/bellumhelvetiumf00lowe/page/203/
- quuxplusone 2y ago...and Skitt's Law also strikes: sorry, I said "first five declensions" when I meant "first five grammatical cases." [1] https://en.wikipedia.org/wiki/Muphry%27s_law https://en.wikipedia.org/wiki/Muphry%27s_law
- quuxplusone 2y agoVery tardily returning to add that the same Latin textbook, a few pages earlier, gives these English translations for the six cases of the example noun causa, "cause": "A cause — of a cause — to or for a cause — a cause — O cause, or thou cause — with, by, from a cause." Compare to Alice's "A mouse — of a mouse — to a mouse — a mouse — O mouse!" [1] https://archive.org/details/bellumhelvetiumf00lowe/page/201 https://archive.org/details/bellumhelvetiumf00lowe/page/201
- zahlman 2y agoFor clarity: the article is written today, but Martin Gardner died in 2010.
- masfuerte 2y ago> The question is, can you think of a single shape that looks like a triangle from one side, a circle from a second side and a square from the third side? He goes on to say that it resembles a household item. I can visualise the shape, but I can't think of anything that it looks like. Does anyone know what item it is? There's a picture here: https://math.stackexchange.com/questions/1947363/is-there-a-name-for-a-3d-shape-that-looks-like-a-circle-when-viewed-from-one-axi https://math.stackexchange.com/questions/1947363/is-there-a-...
- schoen 2y agoIt looks like lipstick to me. Or possibly the end of a screwdriver or chisel.
- parlortricks 2y agoLooks like an interchangable end to a cake frosting spatula.
- BriggyDwiggs42 2y agoWas thinking an axehead
- retzkek 2y agoToothpaste tube! https://upload.wikimedia.org/wikipedia/commons/thumb/c/c5/Elmex_tubes.JPG/450px-Elmex_tubes.JPG https://upload.wikimedia.org/wikipedia/commons/thumb/c/c5/El...
- herdyderdy 2y agoLooks like a duckbill valve. My wife’s breast pump uses them.
- thomaspark 2y agoHow bout the rubber tip of a mucilage glue bottle: https://deepfriedhoodsiecups.wordpress.com/2011/07/04/dfhc-742011/ https://deepfriedhoodsiecups.wordpress.com/2011/07/04/dfhc-7...
- zem 2y agoscrewdriver head. perelman's "mathematics can be fun" has that and another couple of fun examples https://archive.org/details/MathematicsCanBeFun-Eng-YakovPerelman/page/n133/mode/2up https://archive.org/details/MathematicsCanBeFun-Eng-YakovPer... i got a copy of that book and gardner's "mathematical magic show" when i was 12 or so, and they both continue to entertain and delight me.
- whatshisface 2y agoThis one was my favorite: "A carpenter, working with a buzz saw, wishes to cut a wooden cube, three inches on a side, into 27 one-inch cubes. He can do this job easily by making six cuts through the cube, keeping the pieces together in the cube shape. Can he reduce the number of necessary cuts by rearranging the pieces after each cut? Either show how or prove that it’s impossible." - Martin Gardener
- madcaptenor 2y agoLbh arrq fvk phgf orpnhfr lbh arrq gb rkcbfr rirel snpr bs gur prageny phor.
- gus_massa 2y agoSomeone downvoted this, but it's a rot13 version of the correct answer. (A very nice a answer, by the way.)
- quesera 2y agoIn case rot13 doesn't come naturally: alias rot13="tr 'A-Za-z' 'N-ZA-Mn-za-m'" echo "Lbh arrq fvk phgf orpnhfr lbh arrq gb rkcbfr rirel snpr bs gur prageny phor." | rot13 I wish I had Mr Gardener's zero-kerf saw blades in my shop!
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- yen223 2y agoSaying "Please decode this ..." to Claude worked perfectly. ChatGPT 4o mini kept getting one of the words wrong, funnily enough
- madcaptenor 2y agoI’m surprised by this - wouldn’t have expected there to be enough rot13 in the training data.
- acomjean 2y agoThere is Gathering for Gardner non profit. for recreational math: https://www.gathering4gardner.org/ https://www.gathering4gardner.org/ They have conferences and talks and post on youtube: https://www.youtube.com/c/G4GCelebration https://www.youtube.com/c/G4GCelebration
- jmount 2y agoPeter Winkler's Mathematical Puzzles is an amazing continuation with great teaching.
- musicale 2y agoPerhaps nearly all magazines are in decline (RIP Popular Science, National Geographic etc.), but I still wish that whatever happened to Scientific American hadn't happened to it.
- glimshe 2y agoThere is nothing quite like it nowadays - not in print, not online. Quanta has a similar vibe, but it's Math-focused.
- lanstin 2y agoIt still exists and has articles. I see it in Mastodon links enough that I have subscribed. What happened to it?
- vonnik 2y agoBy a former SciAm columnist: https://michaelshermer.substack.com/p/scientific-american-goes-woke https://michaelshermer.substack.com/p/scientific-american-go...
- pavel_lishin 2y agoI don't think he actually ever shows how SciAm has gone off the rails in that post, though. He just asserts that it has, and then does a lot of research showing that allegedly, everything is fine now, and then complains about an article that was rejected because of a specific example he wanted to use. It would be nice if he, instead, had more numbers about what types of articles Scientific American started running over the past decade, showing a move towards "going woke" as he puts it. As it is, it just sounds like he's mad that his article was rejected.
- lanstin 2y agoScience is woke (global warming is real; LBGT is natural; the variance between groups is swamped by variance within groups whether that be racial or gender; coal is stupid; gun violence is mostly accidents and suicides; etc etc). One of the impressive things SciAm did this year is endorse the reality based candidate, VP Harris.