Saturday, March 14, 2015

Happy Pi Day

One problem of being an immigrant country is that from time to time we have holiday overload.  And it's happened again.

Friday was Friday the 13th.  Tomorrow is Laetare Sunday, also known as Refreshment Sunday, Mid-Lent Sunday (in French mi-carême), or Rose Sunday.  In the UK, it's known as Mothering Sunday. Laetare Sunday -- about halfway through Lent -- is a day of relaxation from normal Lenten rigours.  In England, servants were released from service for the day to visit their mothers (hence 'Mothering Sunday').  Tomorrow is also the Ides of March, the day Ceasar was warned about.  Then, Tuesday is St. Patrick's Day.   And, on top of all that, today is Pi Day.

But this is not just any Pi Day.  March 14 was chosen as Pi Day because when written numerically -- 3/14 -- it reflects the first three digits of pi:  3.14.  But, today, it is March 14 of the year '15, or 3-14-15 — the first five digits of the number pi. It's a confluence that won't happen again for a hundred years. Mathmaticians are excited. More than that, today, at 9:26 and 53 seconds, both a.m. and p.m., pi will be taken out to 10 digits: 3.141592653.

Just in case you are curious, in 2013, mathematicians calculated the number to an incredible 12.1 trillion digits.


James R said...

As is so often true, my perspective is slightly unconventional from those, like the singer, who venerate π and, for some strange reason, think it worthwhile, even admirable, to memorized its non-repeating decimal. Indeed, π is special and may be worthy of a day, but not because it is a non-repeating decimal that should be memorized. Non repeating decimals are not exactly special, since there are an infinite number of them—all the irrational numbers. There are even an infinite number of them between any two digits! Celebrate Euler's 'e', the golden ratio 'phi', the square root of 2, or just about any number's square root (except perfect squares),

What is special about π is not that it is a non-repeating number that we may waste our precious time memorizing, but that it is the exact relationship between a circle's circumference to its diameter! What is remarkable about numbers is not their 'number' but their relationship. (If only people would stop worrying about numbers and worry about relationships.)

I've met people who brag about memorizing π to, say, 30 places. I tell them, "wonderful", but I know a lot of people, even kids, who have memorized 300 or 3,000 words of Shakespeare.

Thankfully, the current generation is learning relationships of numbers in math class. Perhaps in the future we will celebrate π-Day for its special relationship.

Big Myk said...

I agree. I don't quite know why people would want to memorize pi's digits. Better to memorize something useful like "A High-Toned Old Christian Woman"or "Gunga Din." I included the video only as a modest entertainment. My main point was simply to bring to people's attention this centenary event, where the date expressed in numbers equals five digits of pi and on two moments of the day, expresses 10 digits of pi.

By the way, pi is not only irrational also transcendental, which means that it is not algebraic, which I confess I don't quite follow. As a consequence, however, it is impossible to contruct a square with the exact same area as a circle.

Even Alexander Pope got in on this one in "The Dunciad, Book 4":

Mad Máthesis alone was unconfined,
Too mad for mere material chains to bind,
Now to pure space lifts her ecstatic stare,
Now running round the circle, finds it square.

In his own footnote to this last line Pope writes: "'Running round the circle, finds it square:' regards the wild and fruitless attempts of squaring the circle."