The Professor’s Beloved Equation

This was so beautiful! It couldn’t have been done anywhere else but Japan. The premise is that this math professor has Alzheimer’s, or at least a special form of it, such that his memory is only 80 minutes long. In the movie his memory was shown to have reset every day at the least, so every morning when his housekeeper arrives, the following conversation takes place:

“What’s your shoe size?”
“24 centimetres.”
“My, what a noble number… It’s the factorial of 4.”
“What is a factorial?”
“If you multiply all the whole numbers from 1 to 4, you get 24.”
“What’s your telephone number?”
“Did you say 5,761,445? Why, that’s wonderful. That’s equivalent to the prime numbers up to one billion. In any event, come in.”

And then every day she came in after that, the same thing would repeat.

“What’s your shoe size?”
“24. The factorial of 4!”
“That’s wonderful. What a noble number…”

He meets her afresh every day, and while she goes about her daily chores he disrupts infuses her housekeeping experience with a good dose of math.

On the day one of the professor’s papers got accepted for publication in a journal:

“Do you often submit your papers to magazines?”
“Right.. I sent my proof to the Journal of Mathematics, Vol. 37 today. That’s good. ”
“Oh, no! I should’ve sent it express. Only first place takes a cash prize.”
“No, there’s no need to send it express. It’s important to arrive at the truth before anyone else, but it’s more important that the proof be beautiful. ”
“Are there such things as beautiful or ugly proofs?”
“Of course. In a truly correct proof, air-tight and compelling reasoning coexists without contradiction, with supple logic. Just as no one can prove why stars are beautiful, it’s difficult to express the beauty of mathematics.” He paused for a beat.
“What’s your birthday?”
“February 20th.”
“What a charming number!” The professor takes off his watch.
“220… Take a look at this. Back in college, I won the President’s award for my paper on Transcendental Number Theory.”
“Ah.. what a great honor..” the housekeeper tried to be relevant.
“No, that doesn’t matter. Can you read the number?”
“President’s Award No. 284. Does that mean you’re the 284th person to receive the honor?”
“I suppose. The question is 284 and 220. This is no time to be washing dishes. Come with me, quick!”

They walk over to the blackboard. The professor writes 220 and 284 on two ends.
“What do you think?”
“Well, I.. Both have 3 digits… How can I phrase this? At the meat counter at the supermarket, if there are two packets of ground beef, one 220g and one 284g, they seem the same to me. One quick glance, and they look similar. They’re both in the 200 range, and all the digits are even…”

“That’s a keen insight. Intuition is important. Grasp the numbers intuitively from your heart. Do you know what a divisor is?”
“Yes, I think so, I remember studying them.”
“Let’s write out all the divisors for 220 and 284, excepting themselves.”
220: 1, 2, 4, 5, 10, 11, 20, 22, 44, 55, 110
284: 1, 2, 4, 71, 142,
“You can calculate all those divisors in your head?”
“I’m just using the same intuition you did. Onto the next step.”
1 + 2 + 4 + 5 + 10 + 11 + 22 + 44 + 55 + 110 = 284
1 + 2 + 4 + 71 + 142 = 220
“Will you behold, this beautiful chain of numbers. Add all the divisors for 284, and you get 220. Add all the divisors for 220, and you get 284. They’re amicable numbers.”
“Amicable numbers?”
“Mm. Such pairs are very rare. Even Fermat and Descartes only discovered one pair each. They’re numbers bound to each other by God’s design.”
“God’s design…”
“Mm. Isn’t it beautiful? Your birthday and the number engraved on my wristwatch are so perfectly intertwined.”

He gave everyone in his acquaintance names, mathematical names that represented their characteristics. To the housekeeper’s son, he gave the name “Root” (of course, pronounced “Root-oh” in Japanese)

“I can tell you’ve a wise heart in here. All right, you’re a Root. You accept any number that comes your way, rejecting none. A truly generous symbol, Root.”

Root starts coming by the house everyday since the Professor cannot stand the idea of Root waiting at home alone for his mother while his mother prepares dinner for a complete stranger. After being thoroughly schooled in the beauty of numbers by the professor, Root goes on to become a math teacher, and teaches his students about the professor’s lifelong equation:

“Pi is the circle ratio, right? “i” is the square root of -1 and an imaginary number. Here we have pi, a number that continues to the ends of the universe, and the imaginary number “i” which never shows itself. What’s tricky, is “e”. “e” is also called the “Napier number,” after John Napier, the British mathematician. The Napier number is one of the constants so critical to math. For now, I’ll just tell you the conclusion. If you calculate this “e”, its value is 2.7182818284…. This is just like pi. It goes on and on and on forever. It’s an irrational number. From an infinite universe, pi drifts down to “e”, and shakes hands with the bashful “i”. They come together, and hold their breaths… none of them are connected. But, if a single human adds just one thing… the world is transformed.
The contradiction is resolved. Zero. In other words, the realm of nothingness embraces them.

Today, we celebrate this equation. When a single human added just one thing to my contradictory and irrational life.

Missing Snow

Saw this link on fb and it had really pretty pics of cornell in the snow:

Is it the Kremlin? #Москва or #Cornell? 😀

A post shared by Nathan Shirley (@nathanshirley) on

No winter maintenance and loving it @cornelluniversity #cornell #westcampus #theslope #ithaca

A post shared by slatersgood (@slatersgood) on

Remember slip sliding down these stairs of doom while on my way back to Risley.

#cornell #snow #ithaca #westcampus #thisarchthingistotesfromrivendell

A post shared by Deirdre. (@dd.licious) on

some nice composition although the photos are pretty grainy sometimes. Don’t people have proper camera phones?

Perfect study view #urislibrary #cornell #snow @cornelluniversity

A post shared by Deirdre. (@dd.licious) on

#Cornell now: Sliding across Bailey Hall plaza.

A post shared by Amy (@aimlessny) on

#Cornell now: The quiet before morning classes.

A post shared by Amy (@aimlessny) on

The next few are by the same person:

#VSCOcam #ithaca #cornell #whatsajuno #newyork @barakbar7

A post shared by Anthony Fairall (@afairall) on

Not Migrating South I Hope // #VSCOcam #geese #upstateny #vsco @barakbar7 #newyork

A post shared by Anthony Fairall (@afairall) on

@foreviper this one is for you // #nosnow #ithaca #cornell #VSCOcam #newyork

A post shared by Anthony Fairall (@afairall) on

Whoever said west coast best coast surely does not know what he’s talking about.

In other news, the New Yorker finally covered Yitang Zhang; the article was both on my fb feed and posted by the math chair here, with a note saying “It gets off to an unfortunate start, with the author confessing his lack of ability in math, but if you get past that, you may enjoy it.” And that piqued my interest because it was so judgy, exactly my style :P So I had a look and agree completely. That author is so narcissistic. If you’re going to be publishing an article on a math genius nobody, I repeat, nobody, in the math world is interested in how much you suck at math. People would read it because of Yitang Zhang, and nobody wants to/should have to sit through one entire paragraph detailing how bad you are at math and how you would likely not even appreciate his accomplishments despite the totally lofty title “The Pursuit of Beauty”, a beauty which I’m sure is lost on you. Journalists need to get a grip.

I was going to upload some posts on our trip to Alaska, (I kept a pen and paper journal while we were there) but since school has started there has been no rest for the wicked. I am greatly looking forward to Friday though where we will head down to the Microsoft campus and sneak in to use their laser cutter to cut out some trivets and coasters. One of our own is having a birthday party on Saturday and we are going to cut a fibonacci spiral trivet for him. Will post the end product here, if I remember to. We went downtown to the Greg Kucera gallery last friday to look at an exhibit featuring aquatint prints of the work of ten famous/noteworthy mathematicians and physicists condensed into a single equation or diagram drawn on a whiteboard.

It was really rather elegant and beautiful; I might recreate them in my house. But with equations of my choosing of course. Since we were downtown we also headed to a wood shop (Woodcraft) and picked up some 1/4″ thick plywood ($6.25), teak colored wood stain ($5), butcher’s block conditioner ($7) (containing beeswax and carnauba wax), two planks of really beautiful 1/8″ thick walnut (~$25), and a sanding sponge at grit level 180 ($2.95) in order to undertake our trivet projects. This whole thing started when we thought of ways to try to hack this beautiful wood trivet

midcentury modern trivet
on food52 that cost $50. Does that sound unreasonable to you? Actually while scoping out the wood shop we found out that solid, dark wood is ridiculously expensive, so it’s not all that surprising that it costs that much. I just.. am not willing to pay that amount :P

so with the skill of seasoned pirates (as only the chinese can be) we created an svg file that looked exactly like the original so as to cut our own trivets with the MS laser cutter.

This was a sample Z’s cousin cut for us out of MDF with the vectorized file we sent him. I stained it with our teak wood stain and then glued it onto Z’s door. Now our apartment feels so “countryside cottage”.. I love it!


Just read this essay without reading the title. Try it! It’s hilarious.

I love the shouts and murmurs section of the New Yorker. Still waiting on my first copy :/ and the accompanying tote bag! Am so sad that I just narrowly missed getting the printed food issue.

School is going ok, first round of midterms are over, thank God. I didn’t do so well on one but did ok on another. Big picture here, is that I learn stuff. And I learnt a LOT of stuff before the midterms, so that’s a plus. Also, found out what else I should pick up (proof skill wise), which is also good. The idea is to keep improving right, until one is less limited.

We almost never have time to go for happy hour anymore, due to the midterms and homework. That and the fact that I go crazy every time we do groceries and wind up buying a ton of stuff that I have to use up. Just yesterday I finally finished 2 of the 3 bell peppers I bought about 3-4 weeks ago in a pasta that also used up leftovers from my dinner at Famous Dave’s last Saturday. I never thought it would happen, but our pantry is FULL. There are 4 bags of pepperidge farm cookies (when they were on sale at $2 or $2.50 each), 6 boxes of Hello Panda, 3 bottles of soda, 1 bag of Wang Wang biscuits, 1/2 bag of Japanese short grain rice (which we are in the middle of using), 20 cans of milo, 1 bottle of calpis, 1 gallon of arizona tea, various cans of tuna, boxes of jello, boxes of matcha pudding mix, a package of egg noodles, basically anything that’s on sale, I’ll buy it. Especially if it lasts forever. I’m beginning to see how Chris managed to stock up her larder to its current war-suitable standards.

We have finally got the styrofoam out of the trunk of the car (that has been travelling around with us for more than a month and taking up ALL of the space in the trunk) because we’d been waiting for a time/reason to drive down to Renton to the styrofoam recycling plant.

For winter break, just for a hoot, we have decided to go to Alaska to try to catch the northern lights. Absolutely worst time to go, weather-wise. I’m not very good at saying ‘no’. So I just said ‘yes’ to this (obviously it wasn’t mine/ze’s idea) and am now part of this bizarre death wish to trek around in Alaska in the dead of winter. Jim Schoenfeldt would get a kick out of this. He’s always told me that the fishing up in Alaska is great, you can catch enough fish to last a whole year, etc.

Oh, my uncle got leukemia. He stays in the Netherlands, so it’s hard for any of us to go see him. My mum and my other uncle got their stem cells tested to see if there’s a match though, for when the first one needs a bone marrow transplant. He’s in the very poor risk category apparently, and my mum has been freaking out about it for a month. She’s the kind of person who doesn’t let things go. I don’t see what she can possibly do to make it better, and you know how uneducated people always try to give old home remedies as advice (to freaking cure cancer)? She’s been telling my cousin to give him supplements and beetroot juice because those are good for him. As if he doesn’t have an entire panel of dietitians in the hospital figuring out what he should eat and what meds go with the chemo.

She worries so much that people worry more about her than about my uncle, who is positively transcendent about this whole thing. He even recorded a message on whatsapp telling her not to worry, but when she’s gotten it into her head to worry, nothing is going to change that. It’s annoying as hell and there’s no talking to people like that. She gets offended when I’m cavalier, she gets offended when I don’t ask enough, she gets offended when I’m not concerned enough, etc. etc. And not being all cut up about it and stressed like her is also offensive. Gah.


School has started and we’re right in the thick of things. 3 (hard) problem sets a week, I’m amazed I’m keeping up at all after 2 years of slacking my ass off. I’m not doing it well of course, just well enough to keep my head above the water.

I like the teachers at U* a lot. They’re really funny and/or personable, apart from the one who keeps nagging us to keep up with the homework like a grandfather. I know he means well but it makes me feel like rebelling haha. Also I think they are a lot clearer in their exposition than the teachers I had at C*.

Our algebra prof has started offering money for every typo students spot in his notes! $1 a typo. J asked at the end of the class “So when you said you were offering money, you mean… cash, right?”
S: “That’s right! This is it guys, this is your chance to make millions from the comfort of your own home!”
J: “So on Monday, bring cash.”
People have been hunting for typos like clam-diggers and today he shelled out 6 bucks to two different students :P

And the topo prof is also really cute. He’s got a really weird style going on with lots of striped shirts and squeaky heeled shoes, which made me think he was 30+, but it turns out he’s nearly as old as our dads and got his PhD in the 80s :S Last week he closed the door after the lesson started and this student who was late knocked on the door, and he opened it, and was like “Does it not open?” The student said he tried opening the door but it wouldn’t open. Someone else piped out that that’s not possible since undergrads walk into our classroom mistakenly all the time (we have a fixed classroom for all the core grad classes) , so I told him “Why don’t you go out and try it?” He said “Do you want to try it? I would but I’m just worried that if I go out nobody will let me back in.” lol which was so endearing (and also exactly what I was thinking).

Today he was running through the schedule at the end of class. “So, I’ve pretty much said everything I want to say on this chapter and on Friday we’ll start on simplicial complexes… Your homework is also due then, so remember to turn it in… And then on Monday we’ll have the midterm.” And he just stopped there and started packing up his notes. There was a stunned silence in the class where everybody thought oh, did I miss something? Maybe I didn’t pay attention when he announced it. One student finally ventured to ask “Wait, what?” I swear my heart literally stopped beating. And then he burst out laughing and said “That was a joke guys” and all of us were like wth kind of joke is that haha.

ok I gotta go bust my ass for the algebra problem set, so I have time tomorrow to do the topo one, and then we can all start breathing on friday afternoon when the week is over. Pumpkin carving with ggy on saturday! I’m making a lasagna and perhaps matcha creme brulee.


I do like this answer on quora to the question:
Why shouldn’t the smarter, more powerful and more productive portion of humanity cull the rest?

In the Hitchhiker’s Guide to the Galaxy, the planet Golgafrincham did exactly that. They convinced the “useless third” of their world (who they classified as telephone sanitizers, personnel officers, management consultants, insurance salesmen, etc.) that the planet was about to suffer a huge calamity. They then packed all of them onto a ship that was set to crash land into some distant planet. The rest of the planet promised to follow in short succession, which of course they never did.

This worked out great for them until one day they were all killed off by a virulent disease that spread via unsanitized phones.

Moral of the story: it’s impossible to know in advance what kind of people will be useful in the future.

Imagine if some guy during the hunter-gatherer age of human evolution had the same bright idea: let’s get rid of these intellectuals: they don’t hunt; they don’t gather; they just spend all day sitting around and drawing pictures with sticks. Genetic diversity is important, because there’s no certainty what the conditions will be like in the future.

At the same time I think it would be interesting to see what would happen if the phone sanitizers ceased to exist. How much more efficient things would be, or if all systems would just stop because a lot of smart people are also incredibly lazy :P

Ah now I feel like reading the Hitchhiker’s Guide again.

On Time Travel

Stephen Hawking once said, “If time travel is real, where are all the time travelers?” Everyone I talk to thinks this is such a great quote and that it proves that time travel is just a fantasy. But what people are forgetting is that Stephen Hawking is obviously a time traveler.

Think about it. “If time travel is real, where are all the time travelers?” That is exactly the kind of thing a time traveler would say. Everyone’s like “Oh, Stephen Hawking, you’re so smart, of course there’s no such thing as time travel!” Meanwhile, Hawking is probably at the dog track right now winning trifecta after trifecta.

Let’s think about this rationally. If you were a time traveler who had visited the future, and someone asked you point-blank if time travel was possible, what would you say? “Oh, yeah, time travel is definitely possible. In fact, I’m a time traveler—confiscate my gambling earnings”? No. You would make some witty quip and change the subject. Then you would politely excuse yourself, call a bookie, and bet on Duke to defeat UNLV in the 1991 NCAA semifinals, even though they were eleven-point underdogs.

Where are all the time travelers? They’re on Wall Street, smoking Cuban cigars and laughing so hard that tears are streaming down their fat faces. Meanwhile, we’re sitting around like morons, betting our money on random dogs and horses and talking about how smart Stephen Hawking is. He probably didn’t even write his books! If you could magically travel through time, think about how easy it would be to bring back some smart book from the future, retype it, and pass it off as your own.
The following people are also probably time travelers:

  • the woman who married Bill Gates before he invented Microsoft
  • the guy who just happened to be filming JFK when he got assassinated
  • George Foreman (how else would he know to sponsor that grill?)

There have always been time travelers. And anyone who says otherwise probably has something to hide.

– Simon Rich

Finally finished the wedding invite!

I finally cracked open the little pot of amedei Tuscan nutella (which is awesome btw) that Maifen gave me and am dipping pretzel sticks into it – a crazy amazing combination! The sea salt on the pretzels give so much depth. It’s like upper crust Yan Yan and it makes me feel like I’m in my cubicle chalet again.

Anyway, this post is about the wedding dinner invites which we finished last night! Took two nights of TeXing but I am rather pleased with the results


The first page of the wedding dinner invite is usually the Chinese text. We did away with that since neither of us speak Mandarin really nor do any of our relatives. So we decided to quote a Frank O’Hara poem which Mingsee first introduced to me.


The second page is the English invitation, which we have also tweaked quite a bit to be more informal. No more silly handphone numbers for RSVP-ing, everything should be online by now. Don’t you love the Koch snowflake? There’s a rather strange gap in the middle between our names and where the message begins where I intend to write the addressees’ names in silver/mint ink. The outer card itself is a pearly mint color.

LZ did about half the TeXing under my direction (move this up, down, left, right, etc.) and I am happy to report he is much better at TeX than he is at Photoshop lol (which we were using for D&SY’s wedding prezi). I haven’t set up my MikTeX properly on my new laptop yet so couldn’t compile the tex file, especially fancy things like this require a lot of packages/style files and somehow my package manager wasn’t downloading them on the fly.

In other news, this article on image recognition apps is really interesting. I just received the link in my inbox this morning because I subscribed to her newsletter after reading Mr Penumbra’s 24 Hour Bookstore.