Today, “3/14” has been designated as Pi Day, since the date comprises the first three digits of PI.
Pi is a mathematical constant that is derived from the ratio of a circle’s circumference to its diameter. The formula for deriving the area of a circle is –
π R2 or Pi times the radius squared.
The circumference of a circle is found by multiplying the diameter by Pi –
π * D
The unique feature of Pi is that it’s non-repeating. Those digits after the decimal go on forever.
Pi to the first 100 places is –
3.1415926535897932384626433832795028841971693993751058209749445923078164062862089986280348253421170679
Carl Sagan gave some attention to Pi in his first contact novel Contact (also made into a film starring Jodie Foster as astronomer Dr. Eleanor “Ellie” Arroway, who is one of the first people to identify an interstellar signal as a communication from an extraterrestrial intelligence. The novel treats with the great issues of science vs religion (more accurately spirituality) and closes with Sagan revealing a message hidden deep within the sequence of numbers comprising Pi – a suggestion that our universe was created.
Pi has also featured in charges leveled against politicians; in 1897 a bill was introduced before the Indiana State Assembly that would have altered Pi’s value by legislative fiat. Apparently, some politicians don’t understand that math does’t work that way.
At the current time, Pi has been calculated out to 10 Trillion places – 10,000,000,000,000 (as of 2011). No secret messages have yet been revealed.
A number of websites celebrate the joy of Pi –
The Joy of Pi; The First One Million Digits of Pi, The Exploratorium…
Some Pi jokes can be found here.
There’s always one, right? Vi Hart has taken a personal stand against singling out Pi for special celebration. You can find a bunch of her rants here.
Take some time today to enjoy your Pi. Whatever flavor it happens to be.