# But what do you eat on “Tau Day?”

Replace Pi with…Tau?

“I know it will be called blasphemy by some, but I believe that pi is wrong.”

That’s the opening line of a watershed essay written in 2001 by mathematician Bob Palais of the University of Utah. In “Pi is Wrong!” Palais argued that, for thousands of years, humans have been focusing their attention and adulation on the wrong mathematical constant.

Well, okay, fine. It’s not like we’re married to pi or anything. We can have other numbers. I’m actually a big fan of the Golden Ratio, myself. But:

Two times pi, not pi itself, is the truly sacred number of the circle, Palais contended. We should be celebrating and symbolizing the value that is equal to approximately 6.28 – the ratio of a circle’s circumference to its radius – and not to the 3.14’ish ratio of its circumference to its diameter (a largely irrelevant property in geometry).

But wait a minute: 2Ï€r is circumference of a circle, but Ï€r2 is the area. So if we move to tau, you’ll just have to take half of tau before multiplying it by r2 to get the area, just as you have to double pi now to find circumference.

So how is tau any more a “truly sacred number” than pi?

Most importantly:

Last year, Palais’ followers gave the new constant, 2pi, a name: tau. Since then, the tau movement has steadily grown, with its members hoping to replace pi as it appears in textbooks and calculators with tau, the true idol of math. Yesterday – 6/28 – they even celebrated Tau Day in math events worldwide.

But on Pi Day, we get pie. Case closed.

(Cross posted at The TrogloPundit.)

## Leave a Comment

### Share this!

Enjoy reading? Share it with your friends!

Send this to a friend