10: Pi Equals

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Pi Equals
My most famous drawing, and one of the first I did for the site
Title text: My most famous drawing, and one of the first I did for the site

[edit] Explanation

There are two possible references here. One is from the book Contact by Carl Sagan, where the existence of God was shown in the last chapter to be encoded in the digits of pi. The other is an old joke of a fortune cookie with a fortune that reads "Help! I'm trapped in a fortune cookie factory!" Similar jokes are often repeated for any mass-manufactured personalized item, often implying that the worker who made the item is working in a sweatshop somewhere or is literally trapped inside a factory and calling for help via the items he produces. This joke is also referenced in 327: Exploits of a Mom's title text, where Mrs. Roberts daughter's name is "Help I'm trapped in a driver's license factory."

The most literal interpretation of the joke would be that some being who helped to create the universe in a "universe factory" snuck a message into the digits of pi (a number that has an endlessly long decimal that never repeats) asking for help to get out. Mathematical concepts being manufactured in a factory is the main mental image here. One can't help but wonder if the primordial beings who labored on the universe to produce things like the gravitational constant and pi have a labor union. Judging by the fact that they're calling for help, it seems they don't.

Since pi never ends and does not follow any sort of known pattern, if each number pair were assigned a letter from the alphabet, or if it was converted to base-26 (or preferably ASCII or some other form of text encoding, if you desire capitalization and punctuation), the entire works of Shakespeare, as well as any other expressible piece of information, including the message in this comic, could be found; although the probability of finding any given string of numbers within a calculable range of digits of pi diminishes rapidly as the string length increases.

Interestingly enough, this could also work for pictures if you assign a set of nine numbers to equal an RGB hexadecimal color value, eventually you will find the Mona Lisa.

[edit] Transcript

π = 3.141592653589793helpimtrappedinauniversefactory7108914...

[edit] Trivia

  • This is the eleventh comic originally posted on livejournal. The previous was 9: Serenity is coming out tomorrow. The next was 14: Copyright. View archive here.
  • The book version of this comic (in xkcd: volume 0) has different title text: "I've put rescue instructions in e. You'll need the cheat codes for your universe, which I hid in the square root of two."
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Discussion

Interestingly, 7108914 does not occur in the first 100,000 digits of pi. However, 71089 does occur at roughly around the 2,500 digit mark. --DanB (talk) 18:17, 6 August 2012‎ (UTC)

7108914 position 13,709,690 counting from the first digit after the decimal point. The 3. is not included. --whitecat (talk) 10:43, 7 August 2012‎ (UTC)

There is a children's book called "Help, I'm a prisoner in a toothpaste factory". 86.30.117.77 (talk) 17:13, 7 January 2013‎ (UTC) (please sign your comments with ~~~~)

or it's reference of the Mac OS 6 and 7 "BlueMeanies" easter egg "Help! Help! We're being held prisoner in a system software factory!". 46.126.181.133 (talk) 08:59, 7 January 2013‎ (UTC) (please sign your comments with ~~~~)

In my profession - simplifications of π is equal perfection, I can throw a recurring function at it, but it will just give me more pages of numbers. Remember that pi will ultimately equal 22/7, and you'll be alright. - E-inspired (talk) 09:17, 3 March 2013 (UTC)

We still have to find "helpimtrappedinauniversefactory" @pi, even when Randall also does not know.--Dgbrt (talk) 20:48, 23 June 2013 (UTC)

You know, we could convert "helpimtrappedinauniversefactory" to the ASCII numbers and then use one of those algorithms that searches pi for a particular string of numbers... 108.162.219.36 22:40, 13 November 2013 (UTC)

While the string 72697680 (HELP) appears multiple times throughout the first 200,000,000 digits of pi (not counting the 3.), none of the resulting ASCII strings makes sense. The closest (7269768022774869990317421141) is at position 31,961,494 with the resulting string as "HELP�M0E". Note that it is the number "0" and not the letter "O". The string "104101108112" ("help") does not occur in the first 200,000,000 digits. -108.162.250.114 08:15, 30 December 2013 (UTC)

Umm... "Of course, because pi never ends and never repeats, if you assign each number pair a letter from the alphabet and look through the digits of pi, somewhere within it is the entire work of Shakespeare, or any other piece of information that could be expressed with human language. So, ironically, somewhere in pi, there actually is the phrase stated in the comic, in a sense." This isn't guaranteed. Just because it's infinite and non-repeating doesn't mean that every possible pattern exists within it. 0.1010010001000010000010000001... is infinite and non-repeating, but it most certainly doesn't contain Shakespeare. It would only be guaranteed if the series was perfectly random over an infinite amount of time. 108.162.237.64 23:47, 14 March 2014 (UTC)

Ah, but in 0.1010010001... there is a pattern, isn't there? 1, then n number of zeroes, where n is incremented by 1 each time it is used. I don't see such patterns in 3.14159... myself. :PNSDCars5 (talk) 12:56, 23 May 2014 (UTC)
That you don't see a pattern doesn't mean there is one. That there is no pattern doesn't mean it contains every possible sequence. --108.162.231.98 12:14, 6 August 2014 (UTC)
Have edited it to add that this requires a proof that pi is normal. For readers, to see the flaw in NSDCars5's reasoning, consider how he might have seen the entire infinite sequence of pi's digits, then realize it's impossible without a formal proof. Which is what the proof of pi being normal would solve. As it is, we don't have that proof yet, and so we cannot say for sure that pi has every possible finite sequence. 103.22.201.63 16:31, 12 August 2014 (UTC)
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