# Pi(e) by Mikey Yang '05

No, not π times *e*.

Yes, I’ll admit that when I first wrote “Pi(e)”, I thought of *π* times *e* even though I meant “Pi/Pie”.

Anyways, as Pi Day approaches, I thought I’d put up a post that collects some of the best pi(e) references out there. For those who are awaiting news on Pi Day, I hope this will be a fun diversion for you as you wait. And for those who are not awaiting such news, here are some fun pi(e) references!

From yesterday’s Today’s Big Thing:

And, of course, the Pi Song:

And actually, if you play both of these videos at the same time, you get an interesting little meta-mashup. (Love you, YouTube Doubler!)

One of my colleagues also made an apple pie for the office today and I was going to take a picture of it, but by the time I remembered, it was all gone. Instead, I give you a transcript of the email that was sent this morning:

From:Erin

To:MIT Admissions Office

Subject:Apple Pie

Date:Thurs, March 10, 2011 at 8:52AMGood morning,

There is delicious apple pie made by Jamilla in the fridge! Please come have a piece!

Erin

**Edit/update, 3/14/11, ~8pm:** Some more great pi(e) references:

A pretty sweet video posted by Corey on Elizabeth’s “Pi-nal Countdown” blog post:

Courtesy of my colleague Ingrid:

http://wordplay.blogs.nytimes.com/2011/03/14/numberplay-pi-in-the-sky/

Today, for Pi Day, Kris brought in a chocolate cream pie, which was quickly consumed (but at least I got some pictures this time!)

(To the right of the half-eaten pie you’ll also see some homemade Amish friendship bread that Matt brought in, too!)

Here is a picturesque slice cut by Kirsten (my attempt at cutting a piece was awful and too quickly consumed to have been photographed – NOM NOM NOM):

So, feel free to post your favorite pi/pie reference(s) in the comments below and I’ll add them in! Do you have a favorite *pi* song? Or, you could make your favorite flavor of pie and send in a picture (mine’s pumpkin)! Or you could try making a pie in the shape of *pi* while singing your favorite *pi* song and reciting the digits of *pi*…the possibilities are endless…

@comments above me:

mind = blown

@anonymous

that’s Euler’s identity

he was 22 when he discovered that, so don’t worry: there should still be some time left for you to go :-D

Haha well I knew they were from Euler’s identity, but I’d never seen those particular manipulations of it. :3

@Saurabh winrar.. nooo just use your browser.

e^π – π ≠ 20

http://www.wolframalpha.com/input/?i=e^π+-+π&sourceid=Mozilla-search

e^π – π ≈ 20

My favorite pi reference/allusion/keepsake-:

MIT

and yes I repeat, MIT!

Sorry, Wolfram|Alpha is temporarily unavailable. Please try again.

Error: DataPacletFilter: Unable to get Connection Cannot create PoolableConnectionFactory (Communications link failure Last packet sent to the server was 0 ms ago.)

When someone mentions something I am not familiar with, I look it up. I feel like there’s so much to learn, so much to discover, yet not enough time to accomplish everything I want. Does anyone feel the same way?

http://xkcd.com/217/ This comic seems appropriate for this conversation.

e^π – π = http://www3.wolframalpha.com/Calculate/MSP/MSP113119ef8f3df8gafddc0000526d27dii1ff9a4e?MSPStoreType=image/gif&s=47&w=496&h=1282

@Sam – lol

@Sam – lol

<3 WolframAlpha.

If you take the geekiest numbers in the world (42 and pi) and divide them by each other (42/pi), you get another geeky number: 13.37 (leet, for those who can’t read it.)

on the interval [0, 1], ∫4/(1+x^2) = π

on the interval [0, 1], ∫4/(1+x^2) dx = π

..whoops forgot the dx

4(1-1/3+1/5-1/9+1/11-1/13+…)= π

Just looked up pi in wikipedia and learned a bunch of interesting properties!

http://en.wikipedia.org/wiki/Pi

We’re all suffering from pimania.

Pi is beautiful, even in musical form.

Many thanks to Mr. Linday. I had never seen Euler’s identity manipulated that way before. That first step got me thinking. With the help of that, a TI-84, wolframalpha, a blank sheet of paper, and some time I figured out why Euler’s identity works and how to raise numbers to imaginary powers.

xi*y = cos(y*ln(x)) + i*sin(y*ln(x))

For any still confused, apply that to ln(-1) (or e(some numbers) = -1 to find out why i*pi fits in “some numbers.”

Math is awesome.

I apologise that the last post has no superscript. For some reason, despite the assurance “you may use HTML tags for style,” they are not working.

@Pavel yeah that’s right. if I’m not mistaken that identity can be demonstrated using Taylor series for e^x, comparing it to the power series corresponding to sin(x) and cos(x).

“Math is awesome.” 100% agreed.

See the value of pie upto 10 million places here! I calculated it! http://sites.google.com/site/csnitclub/downloads/Pi.txt

Open it using the viewer in winrar, the usual notepad is unable to open it because of its size!

Whats really crazy is that e^iπ +1=0

http://tauday.com/

Also, π^2/6 = 1 + 1/4 + 1/9 + 1/16 + … for the sheer sense of bewilderment it inspires.

e^π – π = 20

π = ln(-1) / sqrt(-1)

No one can make a better pie than me. I’m the best cook from the East Blue!

Actually, all of you are wrong. The title refers to the function π(x) evaluated at e (Euler’s constant), which gives the number of primes less than or equal to e (1).

“Powerful Quake and Tsunami Devastate Northern Japan!!!!!!!!!”

Stop worrying about the damn Pie!!!!! :@

I love chocolate cream pie!!!

@ Black Leg Sanji

Yes, as a pi(e)rate your pi(e)les of pie are great!

Happy Pi Day everyone!!!!!!!!!

All real engineers know that:

π / e = 1

also, e^(π * sqrt(163)) is an integer

@Ryan Landay I really don’t think so buddy. Wolfram alpha says otherwise. I reckon it’s another approximate.