Welcome to the newest edition of ** The Why**. “

**Why is Pi important**?” you ask? Good question. (Besides, it still beats answering the question: “Why do high school nerds suddenly become more attractive just because they learn stuff about computers?”

*Because even though it’s 2015 women who have equal rights still all like having a man who can pay the bills while they sit at home watching daytime TV, mmmkay?*)

As various sources have reported, March 14 is “Pi Day”. Steven Strogatz of *The New Yorker *says: “Every March 14th, mathematicians like me are prodded out of our burrows like Punxsutawney Phil on Groundhog Day, blinking and bewildered by all the fuss.”

He notes that “this is the Pi Day of the century: 3.14.15. Pi to five digits. A once-in-a-lifetime thing.” He jokes: “Just stay off the streets at 9:26:53, when the time will approximate pi to ten places: 3.141592653.”

OK but why is Pi important? Math whiz Strogatz says: “Pi does deserve a celebration, but for reasons that are rarely mentioned.”

(We learn about it for the S.A.T.s and then most of us forget it. So why is Pi important?)

Strogatz responds: “The beauty of pi, in part, is that it puts infinity within reach. The digits of pi never end and never show a pattern.”

They seem to be random. But they can’t be, right? Strogatz confirms “they can’t possibly be random, because they embody the order inherent in a perfect circle. This tension between order and randomness is one of the most tantalizing aspects of pi.”

He adds that there are “formulas in which an endless procession of smaller and smaller numbers adds up to pi. One of the earliest such infinite series to be discovered says that pi equals four times the sum 1 – + – + – + ?.” This formula “connects all odd numbers to pi, thereby also linking number theory to circles and geometry” and “joins two seemingly separate mathematical universes, like a cosmic wormhole.”

OK Pi is different from all the other numbers? Strogatz explains: “For those of us interested in the applications of mathematics to the real world, this makes pi indispensable.”

He elaborates: “When structural engineers need to design buildings to withstand earthquakes, pi always shows up in their calculations. Pi is inescapable because cycles are the temporal cousins of circles; they are to time as circles are to space. Pi is at the heart of both.”

Pi is also linked to waves . . . “from the ebb and flow of the ocean’s tides to the electromagnetic waves that let us communicate wirelessly.”

Strogatz concludes: “At a deeper level, pi appears in both the statement of Heisenberg’s uncertainty principle and the Schrödinger wave equation, which capture the fundamental behavior of atoms and subatomic particles. In short, pi is woven into our descriptions of the innermost workings of the universe.”

Why is Pi important? *Now you know.*

*You* ask the questions. * We* provide the answers.

**American Live Wire . . . Listen and be heard.**

*(Since you were so well-behaved during the math lecture, here’s some pie . . .)*