March 14: Pi Day
Edward Johnson, hi-tech and engineering expert, March 14, 2025
The importance of Pi in mathematics
The number Pi (π), whose approximate value is 3.14159, is used to calculate the area of a circle (A = πr²). In astronomy, it is used to determine the orbit of planets: the distance traveled by Earth in one revolution around the Sun is given by 2πr, or about 940 million kilometers. Pi also comes into play in fluid mechanics and thermodynamics, particularly to calculate wave oscillation frequency or thermal conduction models. It is even used in cryptography to generate pseudo-random numbers.
World records related to Pi
In 2022, Japanese computer scientist Emma Haruka Iwao used Google Cloud to calculate 100 trillion decimal places of Pi using the Chudnovsky algorithm, setting a new record. On the memorization side, Indian Rajveer Meena recited 70,000 decimal places of Pi in 2015, a feat achieved in 9 hours and 7 minutes while blindfolded. In 2006, Akira Haraguchi recited more than 100,000 decimal places, although his record was not officially certified.
Unusual facts about the number Pi
In 1897, the Indiana General Assembly nearly passed a law setting the value of Pi at 3.2, an error that would have had disastrous consequences in engineering. Another surprising fact: Albert Einstein was born on March 14, a day that would later become "Pi Day." As for mathematician William Shanks, he calculated 707 decimal places of Pi by hand in 1873, but an error after the 527th digit made the following ones incorrect.
How to memorize as many decimal places of Pi as possible?
The Major System method turns digits into words to create easy-to-remember sentences, where the number of letters in each word corresponds to the digits of Pi (3.141592...). The Memory Palace technique, popularized by Sherlock Holmes, involves associating each series of digits with objects. Rajveer Meena, holder of the official record with 70,000 decimal places, used this method to navigate a mental space filled with numerical sequences. Chunking is another common approach: instead of learning one long string, the digits are divided into groups of 5 or 10, like phone numbers.