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Math

Scientists Calculate Pi To 62.8 Trillion Digits (www.fhgr.ch) 123

OneHundredAndTen writes: Pi is now known to 62.8 trillion decimal digits. Motherboard adds: Researchers in Switzerland broke the world record for the most accurate value of pi over the weekend, the team announced on Monday. They calculated the first 62.8 trillion digits, surpassing the former record by 12.8 trillion decimal points. Calculation first started in late April at the Competence Center for Data Analysis, Visualization and Simulation (DAViS) at the University of Applied Sciences in Graubünden, Switzerland. The calculated data was then backed up onto the high-performance computer where a Y-cruncher wrote it into the hexadecimal notation. It was then converted into the decimal system and verified by a mathematical algorithm
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Scientists Calculate Pi To 62.8 Trillion Digits

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  • by HanzoSpam ( 713251 ) on Tuesday August 17, 2021 @03:09PM (#61702307)

    Print the damn number already!

  • Researchers divided by zero leaving a rather large and ominous hole near a coffee shop in northern Switzerland.
  • by Mikkeles ( 698461 ) on Tuesday August 17, 2021 @03:15PM (#61702325)

    "...surpassing the former record by 12.8 trillion decimal points."

    There is only (at most) one (1) decimal point in any real number.

    Pedantry rule!

  • Oh, and you can only have one decimal point..

  • Far be it from me to critique someone else using cycles, but do we have any actual use for more bits after 50 trillion?

    • Yes, to test pi calculation algorithms and also for proving certain pi-related conjectures in number theory (for example --not pi related, but a counterexample to Euler's sum of powers conjecture wasn't discovered until 1966 because a computer was needed to exhaust the possibilities).

      • I'd really like to see the follow-up research where the output is used in some way. Get that shit into the firehose.

        Otherwise, it's just a big dick contest.

    • Comment removed based on user account deletion
    • by pr0t0 ( 216378 ) on Tuesday August 17, 2021 @03:46PM (#61702473)

      To me, the super interesting thing is that as an irrational number, there is no repeating pattern among those 62,800,000,000,000 digits. For a circle; a shape that somehow feels like a pattern should emerge. I mean...why? How? To someone who is just okay at mathematics, as opposed to someone who has a PhD in it, pi just seems fascinating to me.

      Also, this site that searches the first 200M pi digits for any given set of numbers [angio.net] is kind of cool for no real reason.

      • by cfalcon ( 779563 ) on Tuesday August 17, 2021 @04:10PM (#61702589)

        Sure, you say "no repeating pattern" like it is a good thing, but pi is infinitely long, so any given finite pattern will appear. Any and every given computer file, past, present, or future, is just a finite pattern, so what you fail to understand is that there is an infinite amount of child porn in pi's binary expression.

        Someone should contact Apple to scan it....

        • Sure, you say "no repeating pattern" like it is a good thing, but pi is infinitely long, so any given finite pattern will appear. Any and every given computer file, past, present, or future, is just a finite pattern, so what you fail to understand is that there is an infinite amount of child porn in pi's binary expression.

          Someone should contact Apple to scan it....

          I was wondering where you were going with that. Well played sir.

        • by quenda ( 644621 )

          so any given finite pattern will appear. Any and every given computer file, past, present, or future, is just a finite pattern,

          OMG, so any given file can be represented by just two integers: its length, and an index to its position in the expansion of pi !? This new compression algorithm will make me rich!

           

      • by ShanghaiBill ( 739463 ) on Tuesday August 17, 2021 @04:13PM (#61702601)

        as an irrational number, there is no repeating pattern

        If there are no repeating patterns of digits, PI is a Normal number [wikipedia.org]. If a number is "normal" in all bases, then it is said to be "absolutely normal".

        PI is believed to be absolutely normal, but there is no proof of that.

        Not all irrational numbers are normal. For instance, 0.1010010001000010000010000001 ... is irrational and transcendental, but is obviously not normal.

        The vast, vast majority of all real numbers are normal noncomputable numbers. But we know of almost no numbers that are N-N. Pi is not (it is computable). Chaitin's constant [wikipedia.org] is N-N, but we don't know, and never will know, more than the first few digits.

        • by truedfx ( 802492 )

          If there are no repeating patterns of digits, PI is a Normal number

          That's not what a normal number is, that's what an irrational number is. Follow the link you gave to see what a normal number is.

          For instance, 0.1010010001000010000010000001 ... is irrational and transcendental, but is obviously not normal.

          This number has no repeating pattern, but as you say it's not normal.

      • by hey! ( 33014 )

        Saying there is no repeating pattern doesn't necessarily mean what it sounds like. There are plenty of patterns that are repeated *infinite numbers of times*, but not in any regular pattern.

        For example the sequence "14159" shows up three times in the first million digits.

      • by HiThere ( 15173 )

        Since I believe the universe is finite, I also believe there is a point beyond which calculations of any of its constants are non-applicable. Pi, as it happens, only applies in a flat space-time, which we do not live in. A good approximation of pi is quite sufficient. Probably after a thousand digits or so the space-time of the flattest part of the universe, which we do not inhabit, diverges from the abstract value implied by a flat and continuous space-time.

        That said, I'm willing to believe that there m

        • by quenda ( 644621 )

          It has been reported that NASA only uses about 15 digits of pi.

          15 digits is just what you get from standard 64-bit floating point, with a 52-bit mantissa. The same precision used by a school-kid in his flappy-bird program.
          It is way, way more precision than anything needed for celestial navigation.

    • by kenh ( 9056 )

      do we have any actual use for more bits after 50 trillion?

      I'm curious, how long would it take someone to type all 62.8 trillion digits on a calculator?

      After the first 50 or 100 digits, does it really make any difference what digits you add to the number? It would be just as accurate to simply start adding random digits to the end

  • by perpenso ( 1613749 ) on Tuesday August 17, 2021 @03:20PM (#61702343)

    Scientists Calculate Pi To 62.8 Trillion Digits

    Relax folks, your computer/phone will only handle 15 digits. There is no need to start memorizing pi beyond that. :-)

    • by Mal-2 ( 675116 )

      15 digits was good enough to get New Horizons to Pluto. I think it will be good enough for deciding how much fencing to buy for your round garden plot.

      • 15 digits was good enough to get New Horizons to Pluto. I think it will be good enough for deciding how much fencing to buy for your round garden plot.

        Only because it had a motor and fuel and could do mid course corrections. When we toss unguided rocks around the solar system we will need more digits. ;-)

        • I don't believe adding more digits of PI would help even a tiny bit with course corrections. As planets/moons/asteroids are not perfectly smooth and evenly dense spheres, any slingshot maneuver used to accelerate/decelerate will require course corrections. And of course, very tiny effects from microgravity, solar wind, space dust, etc. add up over sufficiently long periods of time, requiring more course corrections. Plus thrusters aren't 100% perfect either, and neither are the instruments used to measure p

          • Huh, first attempt at a response was anon, don't remember clicking that button ... must have.

            I don't believe adding more digits of PI would help even a tiny bit with course corrections.

            Well I was not thinking just Pi but all numeric values and computations supporting more significant digits.

            As planets/moons/asteroids are not perfectly smooth and evenly dense spheres, any slingshot maneuver used to accelerate/decelerate will require course corrections. And of course, very tiny effects from microgravity, solar wind, space dust, etc. add up over sufficiently long periods of time, requiring more course corrections.

            To stick with the more digits theme, this seems to be a problem of the number of parameters not the digits.

            Why on Earth would you EVER want someone to toss unguided rocks around the solar system. IMO one of the best lines ever in a sci-fi novel... Q: "What are we going to do, throw rocks at them?" A: "Yes."

            My joke was "The Expanse" inspired. :-)

      • by ShanghaiBill ( 739463 ) on Tuesday August 17, 2021 @04:18PM (#61702625)

        My son can recite PI to 100 digits but can't remember his cell phone number.

        • LOL. Thank you. That is the funniest post I've seen on Slashdot in a long time. ;-) I would mod you up but I already posted on this one.

        • My son can recite PI to 100 digits but can't remember his cell phone number.

          LOL. I remember when I could remember friends and families numbers, do math in my head, etc. Damn electronic marvels ruined all that.

        • My son can recite PI to 100 digits but can't remember his cell phone number.

          He just needs to find which bit of PI his cell phone number is first quoted in, and learn up to the end of that.

        • Go find who has phone number +1 (415) 926-5358 and get them to transfer their phone number to your son.

          • by Chaset ( 552418 )

            As it turns out, 415 is a densely populated area (San Francisco) and had to split multiple times in the last few decades. It's quite possible that the number in question exists.

        • Set his unlock code to his phone number. He'll memorize it in no time. That's actually how I got my kids to learn my phone number, the shared tablet suddenly had the unlock code equal to my number.
    • I've been using this mnemonic for decades:

      "How I need a drink! Alcoholic, of course, after the tough chapters involving quantum mechanics."

      This is pi to 14 decimal places if you count the number of letters in each word and put a decimal after the initial 3 for "How".

      I did a Google search for "mnemonics for pi" and found this page, which includes the one I used and a few variants of it.

      https://www.mnemonic-device.com/arithmetic/pi/ [mnemonic-device.com]

      P.S. I was amused by this shorter one: "How I wish I could calculate pi" But

  • by PetiePooo ( 606423 ) on Tuesday August 17, 2021 @03:23PM (#61702359)
    ... which happens to be (almost) exactly 20 billion times Pi.
  • No need (Score:3, Funny)

    by backslashdot ( 95548 ) on Tuesday August 17, 2021 @03:27PM (#61702379)

    Frankly, 3 is good enough a value of pi for any and everything. If it's good enough for God (1 Kings chapter 7, verse 23) it ought to be good enough for anyone. Besides, do we even have proof the value of pi isn't 3? It seems like a globalist conspiracy to set the value of pi to something complicated the average person can't understand. Just another way for the elites to control us. My grandpa used 3 as the value of pi, and his father before that too.

  • Some people really want to know that circumference. No excuse for being sloppy anymore!.
  • I'm quite sure what the point of this is - although if they discovered something like free, nonpolluting, infinite energy, I would say it was worth the effort.

    • we have close enough in the sky, a fusion reactor with over four billion year supply of fuel.

  • Carl Sagan wants to know: Did they find the circle yet?

  • I wonder if they could have continued on or did they start hitting system limits ?
    • I wonder if they could have continued on or did they start hitting system limits ?

      I expect it is very much a matter of hitting systems limits. These algorithms add digits on each iteration, so there is no mathematical reason to stop at any particular point. However, as the number of digits increases, so does the storage required for the numbers. So if the result is of the order of trillions of digits, then trillions of bytes of storage are needed, just to hold the numbers that are needed to compute the next iteration. Presumably, you give up when you run out of RAM.

  • I understand it is important to be precise but I think it was, something like, 12 digits of Pi you could map our galaxy with a high amount of mathematical accuracy. Does this new number help to map the entire universe? What's after that, the atoms or smaller bits across the universe? Im curious of what we can do with it. Also curious how large a file would be with just this number in it.
    • Also curious how large a file would be with just this number in it.

      If stored in ASCII, the file size is 62.8 TB.

      If stored in BCD, the file size is 62.8 / 2 = 31.4 TB.

      If stored in binary, the file size is 31.4 * 10 / 16 = 19.6 TB.

      • Also curious how large a file would be with just this number in it.

        If stored in ASCII, the file size is 62.8 TB.

        If stored in BCD, the file size is 62.8 / 2 = 31.4 TB.

        If stored in binary, the file size is 31.4 * 10 / 16 = 19.6 TB.

        You should interview for Alexa's job.

    • One digit is one byte in ASCII or UTF-8, so that's 63TB. If you go with BCD [wikipedia.org], you could cut that in half, as each byte holds two base-10 digits. If you convert the fractional portion to two's compliment [wikipedia.org], you could get it down to around 25TiB, but good luck putting it to use in that form...

      See how fun math can be?!?
  • Whoa! They've taken tinkering to epic vistas never before imagined. BTW: WTF is "Graubünden"?
  • If I took the stream of numbers and used it for "generating" d10 results for the rest of my life, would any test for randomness (other than is_this_pi()) fail?

  • by chill ( 34294 ) on Tuesday August 17, 2021 @03:58PM (#61702531) Journal

    For JPL's highest accuracy calculations, which are for interplanetary navigation, we use 3.141592653589793.

    This is an excellent blog entry from the JPL on the precision in calculating pi. https://www.jpl.nasa.gov/edu/news/2016/3/16/how-many-decimals-of-pi-do-we-really-need/ [nasa.gov]

    • I think Bill Gates predicted years ago that nobody would ever need more than 64 digits.
    • At some point not much farther than that you can compute the circumference of the known universe accurate to a distance less than the Planck length. I can't remember but it is something less than 100 digits.

      So I don't see really what use this exercise is.

      • At some point not much farther than that you can compute the circumference of the known universe accurate to a distance less than the Planck length. I can't remember but it is something less than 100 digits.

        So I don't see really what use this exercise is.

        Is Plancking still a thing?

      • Proof, scientists like to prove stuff. We assume Pi is an absolute normal number, but is it? I do not see any use case for this many digits of Pi but I am also not a mathematician.
  • 1st researcher: Looks like we passed the other team when do we stop?
    2nd researcher: about 5 times more than the last record, woah 62.8 trillion digits that oughtta do it

  • Seriously, this is .... useful how?
    • Seriously, this is .... useful how?

      This is the Mathematics department. We don't do useful things here. You want the Engineering department. They do some mathematics I believe, but we don't generally talk about that.

  • Note the start date of April 28 and end date of August 14. Three-and-a-half months running on a 64-core machine with 1TB of RAM. That's some serious computing!
  • Isn't this just an example of use-of-computing-power dick-waving?

  • I remember some talk about a whole string of zeros or 1s coming after billions and billions of digits. Carl Sagan or someone was speculating about it. ...
    • I remember some talk about a whole string of zeros or 1s coming after billions and billions of digits. Carl Sagan or someone was speculating about it. ...

      Now that is the sort thing I would expect if the Universe was tuned.

    • I remember some talk about a whole string of zeros or 1s coming after billions and billions of digits. Carl Sagan or someone was speculating about it. ...

      He did. It was the epilogue chapter of Contact.

      It's very strange, because pi is apparently random, so if you go out far enough you will find every conceivable string in it.

      Ellie found this and thought she had found God.

      Which is such a very strange thing for Carol to write about Ellie, yet he did. Quite the mystery.

  • "The ten last known digits of Pi are: 7817924264"

    That last sentence is considerably less significant than they might think it is.

  • by PPH ( 736903 )

    That's my luggage combination!

  • Personally, I'd be much more interested in the (regular) continued fraction [wikipedia.org] for pi than in the decimal digits.
  • they're well past The Nine Billion Names Of God, even taking into account that each name could have up to nine characters.

    • Technically, eight characters, since the three-character extension has to be .GOD. But since there are 51 allowable characters, there are really 51^8 = 45.7 Trillion Filenames Of God.

  • Who checks that they are correct?
  • I’m not saying anything about why calculate pi to such a degree (volumes have been written).

    However, now I feel the need to see how many digits of pi would be required to convert the radius of the observable universe, and convert it to the circumference of the universe, with an error less than a Plank Length.

    As one does, when such questions arise.

    • You don't need a number with 62.5 trillion digits for any practical purposes:
      The radius of the observable universe is approximately 46.5 billion light-years or 7.04×10^61 Planck Lengths. This gives a volume of the observable universe of 4.65×10^185 Cubic Planck Lengths

      • by sl3xd ( 111641 )

        Of course it's not needed for practical purposes. I was just wondering about how many digits of pi could match the most finicky Engineer's "Meh, close enough" requirements. Mathematicians don't always appreciate such shortcuts, as it falls short of perfection.

        A couple of posts up, somebody linked to a NASA response about how much pi they need [nasa.gov], which is close, but still leaves a little slop. I figure the Planck distance is the minimum anybody could ask for in this universe, so a few more digits of pi are req

  • @msmash : German language has that nice feature, that if you have an antiquated system that cannot display accented (umlauted) german characters, you can use the non-accented character follwed by an "e" instead. ü -> ue
    Graubünden -> Graubuenden

  • They're off by 1 in digit 34586712938456

  • Time to change my password.

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