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This Is How the Number 3.14 Got the Name 'Pi' (time.com)
An anonymous reader shares a Time article: Ancient research on real numbers likely "didn't get improved upon until the age of Newton," says John Conway, mathematics professor emeritus at Princeton University who once won the school's Pi Day pie-eating contest. Sir Isaac Newton recorded 16 digits of pi in 1665, later admitting that he was "ashamed" of how long he had worked on the computations, as it meant that he had "no other business at the time," per the MAA. It was not until the 18th century -- about two millennia after the significance of the number 3.14 was first calculated by Archimedes -- that the name "pi" was first used to denote the number. In other words, the Greek letter used to represent the idea was not actually picked by the Ancient Greeks who discovered it. British mathematician William Jones came up with the Greek letter and symbol for the figure in 1706, and it was popularized by Swiss mathematician Leonhard Euler, Catherine the Great's mathematician, a few decades later. "Euler was a much better mathematician than the people who used [pi] before, and he wrote very good textbooks," says Conway. "He used it because the Greek letter Pi corresponds with the letter 'P'... and pi is about the perimeter of the circle."
Where's my pie for first post?
Even Newton knew that, as per TFA.
that was easy.
... and you have a sliced pie.
If the number had been discovered recently it would probably have been called pizz(a).
I thought Newton only calculated up to 3.14159265358979 (15 digits)
Now would be the perfect time to re-introduce this failed pi legislation
Also tau is the whole pie, whereas pi is half pie.
Who ordered that?
no tau is 2 pie so it is better.
Time to offend someone
Why use a foreign letter and use a false pronunciation? Î or Ï are pronounced as the english P or p. Also Î or Ï are not pronounce as you think. You may see it as ÎαÏ... in the greek alphabet, but αÏ... is either pronounced as af or av, so ÏαÏ... is pronounce the same as tough(as in stronk).
... but yes, it's "that" John Conway.
- Mike
If you're going to mention tau, you have to provide a link. http://tauday.com/tau-manifest...
Lesse... Pi is a unicode character that most computers can display.
It should appear here >>
Nope... Come on...
Or, at the very least, 3.14 is a terrible approximation of pi, which is far closer to 3.141592653589793238462643383279502884197169399375105820974944592307816406286 208998628034825342117067982148086513282306647093844609550582231725359408128481 117450284102701938521105559644622948954930381964428810975665933446128475648233 786783165271201909145648566923460348610454326648213393607260249141273724587006 606315588174881520920962829254091715364367892590360011330530548820466521384146 951941511609433057270365759591953092186117381932611793105118548074462379962749 567351885752724891227938183011949129833673362440656643086021394946395224737190 702179860943702770539217176293176752384674818467669405132000568127145263560827 785771342757789609173637178721468440901224953430146549585371050792279689258923 542019956112129021960864034418159813629774771309960518707211349999998372978049 951059731732816096318595024459455346908302642522308253344685035261931188171010 003137838752886587533208381420617177669147303598253490428755468731159562863882 353787593751957781857780532171226806613001927876611195909216420198938095257201 065485863278865936153381827968230301952035301852968995773622599413891249721775 283479131515574857242454150695950829533116861727855889075098381754637464939319 255060400927701671139009848824012858361603563707660104710181942955596198946767 837449448255379774726847104047534646208046684259069491293313677028989152104752 162056966024058038150193511253382430035587640247496473263914199272604269922796 782354781636009341721641219924586315030286182974555706749838505494588586926995 690927210797509302955321165344987202755960236480665499119881834797753566369807 426542527862551818417574672890977772793800081647060016145249192173217214772350 141441973568548161361157352552133475741849468438523323907394143334547762416862 518983569485562099219222184272550254256887671790494601653466804988627232791786 085784383827967976681454100953883786360950680064225125205117392984896084128488 626945604241965285022210661186306744278622039194945047123713786960956364371917 287467764657573962413890865832645995813390478027590099465764078951269468398352 595709825822620522489407726719478268482601476990902640136394437455305068203496 252451749399651431429809190659250937221696461515709858387410597885959772975498 930161753928468138268683868942774155991855925245953959431049972524680845987273 644695848653836736222626099124608051243884390451244136549762780797715691435997 700129616089441694868555848406353422072225828488648158456028506016842739452267 467678895252138522549954666727823986456596116354886230577456498035593634568174 324112515076069479451096596094025228879710893145669136867228748940560101503308 617928680920874760917824938589009714909675985261365549781893129784821682998948 722658804857564014270477555132379641451523746234364542858444795265867821051141 354735739523113427166102135969536231442952484937187110145765403590279934403742 007310578539062198387447808478489683321445713868751943506430218453191048481005 370614680674919278191197939952061419663428754440643745123718192179998391015919 561814675142691239748940907186494231961567945208095146550225231603881930142093 762137855956638937787083039069792077346722182562599661501421503068038447734549 202605414665925201497442850732518666002132434088190710486331734649651453905796 268561005508106658796998163574736384052571459102897064140110971206280439039759 515677157700420337869936007230558763176359421873125147120532928191826186125867 321579198414848829164470609575270695722091756711672291098169091528017350671274 858322287183520935396572512108357915136988209144421006751033467110314126711136 990865851639831501970165151168517143765761835155650884909989859982387345528331 635507647918535893226185489632132933089857064204675259070915481416549859461637 180270981994309924488957571282890592323326097299712084433573265489382391193259 746366730583604142813883032038249037589852437441702913276561809377344403070746 921120191302033038019762110110044929321516084244485963766983895228684783123552 6582131449576857262433441893039686426243410773226978028073
Nope, your number isn't even substantially more accurate - what's the difference between three significant digits and 25 in the face of infinity? Nearly nothing, except for the fact that it's a rare calculation that gets any real-world benefit from more than three significant digits. (well, outside of banking I suppose...)
--- Most topics have many sides worth arguing, allow me to take one opposite you.
>> what's the difference between three significant digits and 25
Said no computer science major, ever. (Look up the effect of iteration on small differences, then study up on damping, etc.)
nonsense, need a few more digits in machining, optics, space exploration, etc.
What exactly had Lovelace to do with the Difference Engine?
Ezekiel 23:20
what's the difference between three significant digits and 25
Ummm...one is for blacksmiths and one is for astronauts?
The Arabic scholars solved for "unknown thing, " which was translated by Spaniards into Greek as "X." Or maybe Descartes popularized it. http://gizmodo.com/why-we-use-...
Jones came up with the Greek letter and symbol for the figure in 1706...
Umm, the Greek letter is the "symbol." The summary (or actually the Times article that the summary, as usual, plagiarizes, though this time they at least made an awkward attempt at attribution) makes it sound like the Greeks had this letter "pi" but no "symbol" to actually use to write it, which is as absurd as claiming, for example, that Gosset (aka Student) came up with the English letter and symbol "tee"/t to represent the result of his test of statistical significance.
In other news, this article can be much more succinctly summarized as follows: Greeks did not use the letter "pi" to represent this value; William Jones, obviously much later, was apparently the first to do so, and this usage was later popularized by Euler. The selection of this particular letter is likely due to it being the first letter in the Greek morpheme "peri-", 'around' (a bit more general than the article suggests as it seems to be overly simplified compared to other sources on the subject).
R.Mo
Do we really need to invoke Catherine the Great's name to help explain who Leonhard "one-of-the-greatest-mathematician's-of-all-time" Euler was? For me it would be more like "Catherine the Great, a sponsor of the legendary Euler, also happened to do some notable things while leading Russia".
Happy people make bad consumers.
Haven't you heard? Pie aren't round, pie are squared.
"I'm not sure I like the fugnutish tone you used in your post!" -RogL (608926)-
The pi symbol could easily be replaced with something that depicts the representation between radius and circumference, freeing up a tiny bit of learned memory for everyone who uses math. There is no reason to use a purely symbolic constant to represent a naturally occurring relationship. Save the ancient Greek symbols for meaningless artifacts which only occur in math space.
I understand that many people who would write that this is not necessary, would also write that they would not want to have to relearn the new symbol, thereby proving a point that it took too much effort to lean the old one.
Oddly a pie as in pie symbol makes more sense to more people.
There is a reason why so many people forget so much of their math.
https://www.youtube.com/c/BrendaEM
you forgot "in the face of infinity" in your quote.
22/infinity ~= 0%
--- Most topics have many sides worth arguing, allow me to take one opposite you.
Some years ago I had a university professor who was of Greek extraction, and he pronounced the names of the English and Greek letters the same, "pee". The coursework (communications) involved lots of probability distributions, so both came up frequently. You had to pay attention.
...laura
There are methods way faster than a Taylor series. Ramanujan's series adds 8 digits per iteration, so getting to 16 would take two steps rather than 10^15 (a significant reduction). Chudnovsky's method converges even faster.
John Conway, mathematics professor emeritus at Princeton University who once won the school's Pi Day pie-eating contest.
He also invented Life, of course.
systemd is Roko's Basilisk.
Takes something of Archimedes, and makes it his own by giving it a name he gives a faux-Ancient-Greek patina. He stole the other most famous transcendental constant, Oughtred's (or possibly Napier's) 'e', and named it after himself too.
Also, 3.14 is so undeserving to connect with pi, it might as well just be three. What is still amazing is 355/113, the most accurate fraction for pi with a denominator less than 10,000 or so. (I could be off a little, look it up.)
That would be a great joke if the plural of pie was pie.
pi are square is wrong! pi are round. cornbread are square. -stolen from Mitch Hedberg.
OSX pwns.
Fair enough, but just for fun I would like to to live in a country where people know that pi = 4 * integral(sqrt(1-x^2),x,0,1)) --https://www.wolframalpha.com/input/?i=4+integral(+sqrt(1-x%5E2),x,0,1) -- http://i.imgur.com/VyUvzQK.png
The Difference Engine was not a universal computer. It was a polynomial evaluator. You couldn't write "serious programs" for it. Jeez, I had no idea historical ignorance had reached such a level around here!
Ezekiel 23:20
To anyone who knows what they are doing, both pi and tau are simply constants. Absorb either into some constant term, or carry it around with you wherever you go---it doesn't matter. Real engineers, mathematicians, scientists, etc can handle either constant without difficulty. The real advantage that tau has over pi is pedagogical. It is much easier to communicate the relation between angle measure and arc length with tau. Since trig functions deal with lengths more readily than area, it makes sense to teach people trigonometry using a constant that is more closely related to length.
Rhapsody in Numbers
Same AC here, I don't actually understand all of the notation in the link you gave as it is displaying here, I'll have to look it up.
The Unicode on that page is borked. There is a really good discussion on this Stackoverflow page including Chudonovsky's method.
But each iteration of that looks like quite a bit of calculation too.
You could do a few iterations of Chudnovsky in a week. A quadrillion iterations of Taylor's series would take a thousand lifetimes.
That would be the difference between a clock that keeps reasonable time, and one that loses over 40 seconds a day.
I would like to disagree. I don't know how many times I've lost a 2 somewhere in the calculation. Either because of brain malfunction like "right angle = pi/4", forgetting a 2 in 2*pi*r or even adding a 2 in pi*r^2/2 just because the integral of r = r^2/2. I think most engineers and mathematicians have made similar mistakes.
Making sound choices to prevent stupid mistakes is important. Pi is an unnecessary evil.
Also, we should switch to base 6. People make too many mistakes with 6,7,8 multiplication.
Pi is the ratio of the circumference of a circle to the diameter. 3.14 is an approximation of Pi to three significant figures. A closer approximation is 3.14159265359 ... Picking on the sloppy wording in the article.
Pi is an "irrational number" which never has a final concrete value. You just get as close as you need to for the accuracy of what you are trying to do. I remember using Pi out to 13 decimal places in undergraduate physics class.
NRRPT/RCT
So Newton wasn't smart enough to figure out that the true circle constant is Tau, not Pi?
When our name is on the back of your car, we're behind you all the way!
I've got a pie here and I've got a pie there, so I'm pie-winning!
When our name is on the back of your car, we're behind you all the way!