This week's post is a day early because today is Tau Day!

Tau, for those not familiar with it, is the mathematical constant equal to 2 × π (Pi), or roughly 6.28, and is represent by the greek letter Tau: τ. Today (6/28), we're going to look at the internet battle that's erupted over π versus τ since 2010.

The opening salvos in this year's battle were already launched back on Pi Day by DNews, with their Is Tau Better Than Pi? video:



3 days ago, Scientific American continued with their post, “Why Tau Trumps Pi”. Just 1 day later, prooffreader.com jumped in with Pi vs. tau: Ultimate Smackdown.

Starting at about 2:40 into the DNews video above, they come very close to a good answer. Yes, geometry and trigonometry rely heavily on 2π, and in those cases τ makes more sense, especially when it comes to concepts like τ radians in a circle. However, π has plenty of uses beyond those subjects on its own.

I'm in favor of adopting τ as a commonly-used constant, but not as a replacement for π. Talking about τ versus π to me is like getting in a heated argument over degrees versus radians. Which one is better? The answer can be degrees OR radians, depending on the context of the problem at hand. Should we use base 10, base 2, or base e in logarithms and exponents? Again, the answer depends on the context.

Kalid Azad of BetterExplained.com has 3 questions that can make even the toughest math concepts understandable: What relationship does this model represent? What real-world items share this relationship? Does that relationship make sense to me? In fact, as James Sedgwick points out in his essay, “The Meaning of Life”, you only have meaning if you have a relationship set in a context.

Yes, the endless internet battles over Pi versus Tau can be fun, but when it comes down to the important aspects, I believe we should focus on solving the problem at hand, and using the most effective tools. Besides, if we only keep one or the other, that's one less geeky holiday to celebrate in the year.

Happy Tau Day!