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A Much Bigger Piece Of Pi

Punk_Rock_Johnny points to an AP story on Pi-obsessed Professor Yasumasa Kanada. A snippet from the story: "Kanada and a team of researchers set a new world record by calculating the value of pi to 1.24 trillion places, project team member Makoto Kudo said yesterday. The previous record, set by Kanada in 1999, was 206.158 billion places." Trillion! "

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  1. Signature of God? by Speare · · Score: 5, Interesting

    In the book version of Contact by Carl Sagan, but skipped in the Jodie Foster movie, was the notion that the aliens had discovered proof that the universe was created by a higher intelligence. A God or society of Gods far higher and more advanced than the aliens. The whole point of dragging Human-kind to that remote beach to talk with daddy was to tell Human-kind that it was time for them to look for God's signature on this universe.

    As any artist, the creator signed the creation. Where? Deep into the insignificant but irrefutably valid digits of several of the fundamental mathematical constants such as pi and e.

    The main character finds one of the signatures at the end of the book: if calculating digits of pi in base 11, after a few million or billion places, a 500x500 digit span is almost entirely zeros. If the span was rendered as a square of pixels, the non-zero digits drew a perfect circle inscribed in the square. A circle in a square. The key concept defining pi, in the digits of pi itself. The whole way the universe works is affected by that constant, so any such 'design' in it has, if you pardon the pun, a transcendental import.

    Why base 11? It's left to the reader to decide, but I expect Sagan wrote it because it is considered one of the possible designs of the universe, one of the string theories is based on an 11-dimensional all-inclusive physics model. As the alien explains to the main character, it wouldn't be base 10, because what's the likelihood that the creator also happened to have ten fingers?

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    [ .sig file not found ]
    1. Re:Signature of God? by JanneM · · Score: 4, Interesting

      No. The rearranging of bases, sizes, images and so on is just diluting it even more.

      Say we get a trillion digit sequence. Chances are that if you look long and hard enough, widening your parameters for what's acceptable enough, you will find something. Say you accept not just a perfect (according to some pixellization algorightm) circle exactly filling a 500x500 square in base eleven, but a pretty good approximation of any geometrical figure in any base up to some base and with an image size of anything from 32x32 up to those 500x500 - you suddenly have not just one chance per position in the sequence, but millions. That "Bible Code" scam worked exactly the same way - cast your net wide enough and you can't fail to find something.

      Have fun.

      --
      Trust the Computer. The Computer is your friend.
  2. No, pi is irrational by smcv · · Score: 5, Interesting

    Pi is represented usually by a fraction or relatively simple equation, it's just the division that makes the number go on for ever.

    Nope. If pi was rational (a fraction), it wouldn't go on for ever without repeating. (reference)

    In fact pi is irrational, i.e. there are no integers p, q such that pi = p / q. (proof)

    You can approximate pi as a fraction, which is what projects like this do. (pi is approximately equal to 31/10, or 314/100, or 31416/1000, or ... but these are just approximations; 22/7 is a good enough approximation a lot of the time, but that's just an approximation too)

  3. For comparison... by MarvinMouse · · Score: 5, Interesting

    A google only has 100 zeros, thus 100 places.

    10^trillion is 1 followed by 1 trillions 0's... Assuming we are following the american system that would be equivalent to.

    10^(10^12)

    Okay... now.. let's get some interesting facts with this.

    The absolutely smallest length measurable by quantum theory is the planck length which is approx 10^-34 m. Needless to say, if we have a diameter of an incredibly small perfect circle, we'll know it's circumference beyond what is possible by quantum theory (but since there are no perfect circles, and quantum theory adds probability, this doesn't mean anything really useful. :-P)

    Now, since we know the smallest measurable... lets look at what the estimates for the size of the universe are. Recent estimates put it as 10 billion light years in radius source
    Which works out to about... (assuming american notation on billion)

    10^9 * 300,000,000 m/s* 365*24*3600 ~= 10^25 m

    Okay... now if we were to measure the circumference to as accurate as allowed by quantum theory we'd have.

    pi*2.10^25 ~= 6.28*10^26 10^27 with an accuracy of about 34 decimals...

    So... to get perfect accuracy as allowed by quantum theory we would have at most 35 decimal places afterwards... therefore, we'd need pi with an accuracy of

    ~10^63...

    We have pi with an accuracy of 10^(10^12) which is
    63 : 10^12 ~= 1: 1.59x10^11
    Way more accuracy then we really need. :-)

    That's absolutely insane, but it is fun math.

    Just some food for thought.

    --
    ~ kjrose