Pi Day is celebrated around the world on March 14 due to the similarity of the decimal extension of the number to the date “March 14”, which is written in the US in the format 3.14. The first time Pi was celebrated was in 1988 at the initiative of Larry Shaw at the Exploratorium science museum in San Francisco.

What do you possibly not know about Pi?

Pi(π) is the ratio of the circumference length of a circle to the length of its diameter. This number is fascinating, m.in. Because for many years it was very difficult to calculate. The first to do so, with an accuracy of two decimal places, was probably Archimedes in the third century. BC. The Greek mathematician is believed to have been the first to analyze the properties of π in depth. He used geometry in his work.

Many authors of historical studies in the field of mathematics emphasize that π was generally treated by the ancients in a practical way. The Babylonians were content with 3,125 and the Egyptians with 3,143. Interestingly, many Egyptian structures contain an approximate value of Pi in the various relationships between the dimensions of the objects. An interesting fact is that one of the wonders of the world, which is the pyramid of Cheops, contains in its dimensions the number π with an accuracy of four decimal places. When the researchers calculated the ratio of the sum of the two sides of the base of the building to its height, it turned out to be 3.1416! To this day, there are debates as to whether this was a coincidence or whether one of the builders was an unknown genius. Information about π is even found in the Holy Scriptures. From 1 Kings 7:23 it can be inferred that Pi is equal to 3.

In 1596, the mathematician Ludolf van Ceulen calculated the value of Pi with an “astronomical” accuracy of 20 decimal places, and before his death he managed to improve the result to 35. The number Pi was engraved on his tombstone, so it is thanks to Ludolf van Ceulen that Pi is sometimes called “Ludolfina”.

The first modern formula to calculate Pi is John Wallis’s infinite product of 1655. The same one who introduced the mathematical designation of infinity that we use today.

At the end of the 19th century, the British amateur mathematician William Shanks calculated the value of Pi to 707 decimal places. Since he did the calculations by hand, it took him 15 years!

Nowadays, the latest technology and complex computer algorithms are used to precisely determine the value of Pi. In 2019 Emma Haruka from Google Japan decided to show the world her new achievement. She calculated π with an accuracy of about 31 trillion decimal places. In doing so, it broke Peter Trueb’s record set in November 2016, which achieved an accuracy of about 22.5 trillion decimal places. However, the last word has not yet been said.

Yes! Some people think that the Greek letter π refers to the name of Pythagoras. This is a mistake. It really comes from the Greek word “perimetron” or “periphery” (circumference, periphery).

40 decimal places and the world goes round

The symbol π was introduced by the Welsh mathematician William Jones in his monograph “Synopsis palmariorum mathesos” in 1706. No one can remember its exact value. However, if you want to be sure that none of the calculations you make will cause a disaster, all you have to do is encode about 40 decimal digits in your head (cliché, right?). NASA only needs a dozen or so digits of Pi expansion not to spoil the International Space Station.

In 2005, a Japanese man recited 83,431 digits of π correctly, which was checked and confirmed, and his result was included in the Guinness World Records. (We think we are going to add order to some important discussion if we mention even in passing that there is a 1 digit inthe 100,000th decimal place in Pi and that there is no sequence 123456 in the first million digits.)

Pi has long been an inspiration for parascientists and artists. Ba! π even appeared in the name of the Raspberry Pi platform (the device consists of a single printed circuit board and was invented to support the learning of the basics of computer science). Supporters of metaphysics will probably be pleased to know that among the first 100 million digits of the expansion of Pi they will find every five-digit number, and with a probability of almost 2/3 their date of birth in the DDMMYYYY format.

And one more thing about the magic of Pi

π is the basis of many formulas and problems – in geometry, mathematical analysis, number theory. In the world of physics, it can be found, for example, in Heisenberg’s Uncertainty Principle and in the equations of Einstein’s General Theory of Relativity. The number of π can also be found in other scientific disciplines, such as computer science, architecture or construction.

• The magnetic permeability of vacuum is 4 π*10-7.
• Pi appears in formulas for radius of atom, electron size
• is a factor in the cosmological constant
• It is inextricably linked to the trigonometric calculus, which in turn is used in electronics, wave physics, medicine and astronomy

^Origin:

^{“The World’s Most Fascinating Number – Pi”, focus.pl}

^{“Today is Pi Day,” benchmark.pl}

^{“PI Number Day. What else don’t you know about it, and what should you know?”, gloswielkopolski.pl}

^{“On Friday, the number Pi celebrates its holiday,” naukawpolsce.pap.pl}

^{“The number Pi was revealed during calculations over the hydrogen atom,” ciekawe.org}

^{The number pi – Struggling with ludolphine, histmag.org}