Posted at 10:03 AM ET, 06/28/2011

# Tau Day: Replace Pi, make music with Tau

Relish in the math nerdery afoot. June 28 — or 6.28 — is the day dedicated to pi’s (π) lesser known double, tau (τ). Most grade-school graduates will recognize π, the never-ending ratio of a circle’s circumference to its diameter (3.14159265...). But τ may be a bit more unfamiliar. Tau is the ratio of the circumference to its radius. It also is twice the amount of π (6.283185307179586...).

A selection of mathematicians have engaged in an online battle to draw attention to π, what they consider a more perfect measurement of a circle’s constant. But other numeral-philes, such as Michael Hartl, are trying to persuade the math literati to pay more attention to τ.

Hartl, who says on his Web site that he has a doctorate in theoretical physics and creates Web development tutorials, launched Tau Day last year. In his Tau Manifesto, he wrote: “It should be obvious that π is not ‘wrong’ in the sense of being factually incorrect; the number π is perfectly well-defined, and it has all the properties normally ascribed to it by mathematicians. When we say that ‘π is wrong,’ we mean that π is a confusing and unnatural choice for the circle constant.”

Get it? Good. Now, listen to τ set to music, from “Pi Song” musician Michael Blake:

By  |  10:03 AM ET, 06/28/2011

Tags:  Picture Show