October | 2023 |
1 post published by jamespropp during October 2023| mathenchant.wordpress.com
In ordinary math, the infinite decimal .999… is defined to be the limit of the terminating decimals .9, .99, .999, …; that is, it’s defined to be the real number that the fractions 9/10, 99/1…| mathenchant.wordpress.com
You probably haven’t heard of David C. Kelly; he doesn’t write best-sellers or give TED talks, or study the center of the galaxy or the human genome or the social impact of algorithms. …| mathenchant.wordpress.com
This past week I was saddened to learn of the death of mathematician and teacher David C. Kelly, the founder of the Hampshire College Summer Studies in Mathematics program (HCSSiM). “Kelly”, as eve…| mathenchant.wordpress.com
“I couldn’t help but wonder…” — Carrie Bradshaw (in every episode of Sex and the City) The best birthday party I ever had as a kid was a trip to the Museum of Natural …| mathenchant.wordpress.com
If you ask a person on the street whether 1 is a prime number, they’ll probably pause, try to remember what they were taught, and say “no” (or “yes” or “I don’t remember”). Or maybe they’ll cross t…| mathenchant.wordpress.com
Since you’re reading this essay, you probably already know about the mathematical holiday called Pi Day held on March 14th of each year in honor of the mystical quantity π = 3.14…. Pi isn’t j…| mathenchant.wordpress.com
“Think about the knife tip. That is where you are. Now feel with it, very gently. You’re looking for a gap so small you could never see it with your eyes, but the knife tip will find it, if you put…| mathenchant.wordpress.com
There’s a pretty thought experiment that’s sometimes attributed to Democritus though it’s actually due to a later popularizer of the atomic hypothesis1 and it goes like this: Suppose we use the wor…| mathenchant.wordpress.com
There are mathematical operations of all kinds with the property that doing the operation twice is tantamount to not doing anything at all. Such operations are called involutions, and you can find …| mathenchant.wordpress.com
“Nobody knew math could be so complicated.”— nobody ever The most truthful — and, to me, the most infuriating — thing a certain public figure1 uttered over the course of his ongoing career was “It is what it is.” Given that he was referring to the deaths of over a hundred thousand people — deaths that, […]|
I’m a professional mathematician. That means somebody pays me to do math. I’m also a recreational mathematician. That means you might have to pay me to get me to stop. Wearing my recreational mathematician hat – quite literally, as you’ll see – I gave a talk earlier this year on some newfangled dice that do […]|
dedicated to Norman Skliar and Sidney Cahn In an earlier blog-essay, When 1+1 Equals 0, I explained how 1 + 1 = 0 makes sense in mod 2 arithmetic; today I’ll tell you how the equation 1 + 1 = 1 mak…| mathenchant.wordpress.com
John McWhorter, one of my favorite public intellectuals, writes (in his recent essay “Lets chill out about apostrophes”), “Writing does not entail immutable rules in the way that mathematics does.”…| mathenchant.wordpress.com
No reckoning allowed save the marvelous arithmetics of distance (from Smelling the Wind by Audre Lorde) Suppose a child comes up to you and says “I know 1 is odd and 2 is even, but I think 4 is mor…| mathenchant.wordpress.com
How far would you go to save a theorem? Would you invent a new kind of number? That’s what the mid-19th century German mathematician Ernst Eduard Kummer did, and while he was partly driven by the h…| mathenchant.wordpress.com
To err is human; we all make mistakes. But some mistakes have worse consequences than others. According to Greek myth, King Sisyphus of Ephyra made the especially big mistake of cheating Hades, the…| mathenchant.wordpress.com
