New Record- Pi Memorized out 100,000 places

[Dragwyr]

I have the first 100 decimals memorized. Many have asked me why. I was bored and it was a long drive back home from Tennesee.
Only 99900 more decimals to go.

[Arnold_Winkelried]

@Shoeless

How do they calculate it out to that many digits in order to check his work? I assume they use a computer somehow, but isn’t floating point math on a computer somewhat imprecise?

2.7 trillion digits of Pi are known.
Pi calculated to ‘record number’ of digits (BBC News)
By Jason Palmer, Science and technology reporter, BBC News, Wednesday, 6 January 2010

Fabrice Bellard used a desktop computer to perform the calculation, taking a total of 131 days to complete and check the result.

How did he do it? See here (PDF document)
A sample of the digits from his record calculation:
http://bellard.org/pi/pi2700e9/pidigits.html
From his FAQ:

Where can I download all the computed Pi digits ?
The files have a size of more than 1 TB, so it would take a while to download them, even with a fast Internet connection (e.g. 10 days with a 10Mb/s download speed). Instead, I may add a web page where the user can ask the digits at a specific position.

[Aji_de_Gallina]

@bonitahi

Ají de Gallina

Assuming it was a while back that you were able to pi-out 100 digits, now after ‘x’ amount of time,
how many places-digits can you recite now? Your being out of practice, I am trying to figure the time factor in memory.

I know, small sample survey, but…

Thanks.

I was 22 or 23 so that’s 16 years ago.
On a regular day I remeber 12 or 13, on a really good one maybe 20.
I’m going to try to go back to at least 50.

[lynne-42]

@Exapno_Mapcase

The capacity of the human mind to keep and absorb huge amounts of information in a given order is astonishing and seemingly far beyond that of any animal. It’s an aspect of intelligence that I feel gets far too little attention when the subject is talked about.

I am doing my doctorate on the way scientific knowledge is encoded in oral traditions. There are a large number of mnemonic technologies which have been used to aid memory - some purely oral (mythology, song, chants, rhyme, narrative and so on - technically part of a field of research known as primary orality) and some using physical mnemonic devices. Without writing, cultures were dependent on these technologies to recall all the knowledge of their culture, much of which is pragmatic stuff, such as animal behaviour, plant use, navigation, astronomy (and other calendrical devices), and so on. It is amazing stuff - I am having a ball.

Just a few examples: the Navajo classify over 700 insects into three levels (effectively family, genus and species) - and it is all recalled in memory. (Cite: Navaho Indian Ethnoentomology: Wyman and Bailey). The plant knowledge of the Australian Yankunytjatjara (Cite: Punu by Goddard and Kalotas) is extraordinary in its detail - again all recalled in memory using Songs. The South Sea navigators could navigate the Pacific using massive chants linking stars, wave directions and other natural phenomena, all learned on land before they set off. I am finding all these non-literate knowledge systems are indexed in some way - the “in a given order” that you mention - so knowledge is not lost.

The human memory is extraordinary when trained well. With writing, however, our need to remember is greatly reduced. I really admire these memory skills, but the work load involved in learning the data is just too much. It is why indigenous knowledge systems are lost when there is contact with literacy. Writing is much easier!

[John_DiFool]

@Dragwyr

I have the first 100 decimals memorized. Many have asked me why. I was bored and it was a long drive back home from Tennesee.
Only 99900 more decimals to go.

99,900 slices of pi on the wall

99,900 slices of pi

Take one down and pass it around, 99,899 slices of pi on the wall…

[Gary_Robson]

[moderating]
I know “is this possible?” is a question, but I really think this is better suited for MPSIMS than GQ, so I’m moving it over there…
[moderating]

@bonitahi

Ají de Gallina

Assuming it was a while back that you were able to pi-out 100 digits, now after ‘x’ amount of time,
how many places-digits can you recite now? Your being out of practice, I am trying to figure the time factor in memory.

I know, small sample survey, but…

I’ll double your sample size on timing. When I was a high school junior (let’s call it age 16) I memorized pi to 50 digits. I hadn’t had any use for it in a long time (I’m 51 year old now), and just checked myself. I can still do all 50.

I can barely remember my own phone number some days, but I still know the first 50 digits (after the decimal point, that is) of pi. sigh

[Exapno_Mapcase]

@lynne-42

I am doing my doctorate on the way scientific knowledge is encoded in oral traditions.

I’ll always been fascinated by the mnemonic device called the memory palace, something that comes up frequently in fiction because as a metaphor and plot device, it has endless, um, stories. While Googling, I found has the more technical name of the method of loci.

‘the method of loci’, an imaginal technique known to the ancient Greeks and Romans and described by Yates (1966) in her book The Art of Memory as well as by Luria (1969). In this technique the subject memorizes the layout of some building, or the arrangement of shops on a street, or any geographical entity which is composed of a number of discrete loci. When desiring to remember a set of items the subject literally ‘walks’ through these loci and commits an item to each one by forming an image between the item and any distinguishing feature of that locus. Retrieval of items is achieved by ‘walking’ through the loci, allowing the latter to activate the desired items. The efficacy of this technique has been well established (Ross and Lawrence 1968, Crovitz 1969, 1971, Briggs, Hawkins and Crovitz 1970, Lea 1975), as is the minimal interference seen with its use.

This is something you’re of course familiar with, but others probably don’t know it’s the technical name of how these freakish memorization feats are faciliated even today.

There are countless other devices, and Wiki has a dense page on those as well.

[lynne-42]

@Exapno_Mapcase

While Googling, I found has the more technical name of the method of loci.

I agree that this method is central to a large proportion of memory methods. It is well documented in Frances Yates’ book, The Art Of Memory. Eight time world memory champion, Dominic O’Brien discovered the method himself before he found out its ancient roots, and called it the Journey Method. He still hasn’t found anything which works better.

Some researchers - and I agree - consider traditional cultures’ method of assigning ceremonies to given locations (referred to a sacred sites), as being a form of the Method of Loci. Linking stories, songs and ceremonies to specific landscape places is something I am finding is common to all (that I have researched so far) oral cultures, despite them having no contact with each other. Those ceremonies then serve to preserve the cultural knowledge, including the natural history. It is a totally different way of storing knowledge, though, which is leading me down some very interesting paths! And I have a scholarship, and so get paid to research this stuff. How lucky am I?

Can you tell me some of the fiction it appears in? I am not familiar with that, and it sounds very interesting.

[dhkendall]

I can just see now:

“OK, Mr. Haraguchi, begin reciting the digits of pi.”

“Ahem 3.12-”

BZZT

“Sorry, incorrect. Thank you!”

[Hadrian_s_Wall]

We are actually studying this in neuroscience. Here is a insightfularticle

[Markxxx]

Another useless record. I am amazed at things like this. I hate to be a downer, but there’s got to be a decent use for man who can do this. You know actually do something useful with this ability

[Robot_Arm]

@bonitahi

A Japanese man, Mr. Haraguchi, sounded off pi 100,000 decimal places from memory.

Now he just has to come back.

[CookingWithGas]

@CookingWithGas

…One memory expert described a way to assign a particular image to each of the three-digit numbers up to 999, and to memorize long strings of numbers he would create a story stringing these images together. Now, memorizing 1,000 images associated with numbers is a bit of a feat in itself…

@Hadrian_s_Wall

We are actually studying this in neuroscience. Here is a insightfularticle

The article includes what I’m talking about:

@Discover

To do this, he has memorized a repertoire of images for any combination of three digits between 000 and 999. To Cooke, the number 227 is the mathematician Kurt Gödel starving himself to death. The number 115 is Psmith, a character in several P. G. Wodehouse books. It also stands for the action of giving away someone else’s umbrella and the image of a young lady stranded in the rain. The number 614 has become Bill Clinton smoking (but not inhaling, Cooke notes) marijuana. When Cooke sees the number 227115614, he divides it into three parts and conjures up the images he has memorized for each triplet—“Kurt Gödel offering someone else’s umbrella to a cloud of marijuana smoke.”

I would have trouble memorizing 1,000 images and associating them each with a number.