Because tau day isn’t half as cute. I would have let it pass in silence, but Dr. Ogden’s1 post concerning Buffon’s Needle approach to calculating pi is just too damn cute.
In 1777, a French philosopher called Georges-Louis Leclerc, Comte de Buffon, wrote out a very elegant theorem which turned out to be the earliest problem in geometric probability.
Buffon discovered that if you draw a set of equally-spaced parallel lines (say, d centimetres apart) and drop sticks on them which are shorter than the spacing (say l centimetres long, where l is less than d), then the probability of a stick crossing a line is
2l/πd.
This means that if you drop lots of sticks randomly and count how many cross the parallel lines, you can calculate what π is by rearranging the formula:
π=2ls/cd
where s is the number of sticks you drop and c is the number that crossed a line.
Go see Dr. Ogden’s post if you want the footnotes or more commentary. Or learn about the mathematician who gave it a go by spinning in circles.
Deb’s Raised Game Pie
BTW, the second to last pie I baked was supposed to be lemon meringue, but turned into caramel meringue. We discovered squirrels and other local wildlife would actually eat it.
The last pie I baked was an emergency replacement apple pie.
1Via SciFri via Spaceweather.com.
