# Happy Tau Day! (Or: How Some Mathematicians Think We Should Retire Pi) [Video]

When you were in school you learned all about Pi and its relationship to circles and turn-based geometry. Some mathematicians are rallying for a new lesson, on about Tau.

Michael Hartl is a mathematician on a mission, a mission to get people away from using Pi and to start using Tau. His manifesto opens:

Welcome to The Tau Manifesto. This manifesto is dedicated to one of the most important numbers in mathematics, perhaps the most important: the circle constant relating the circumference of a circle to its linear dimension. For millennia, the circle has been considered the most perfect of shapes, and the circle constant captures the geometry of the circle in a single number. Of course, the traditional choice of circle constant is π—but, as mathematician Bob Palais notes in his delightful article “π Is Wrong!”,1 π is wrong. It’s time to set things right.

Why is Pi wrong? Among the arguments is that Tau is the ration of a circumference to the radius of a circle and defining circles by their radius is more natural and that Pi is a 2-factor number but with Tau everything is based of a single unit–three quarters of a turn around a Tau-defined circle is simply three quarters of a Tau radian.

Watch the video above to see the Tau sequence (which begins 6.2831853071…) turned into a musical composition. For more information about Tau hit up the link below to read the manifesto.

The Tau Manifesto [TauDay]

Jason Fitzpatrick is a warranty-voiding DIYer who spends his days cracking opening cases and wrestling with code so you don't have to. If it can be modded, optimized, repurposed, or torn apart for fun he's interested (and probably already at the workbench taking it apart). You can follow him on if you'd like.

• Published 06/28/11
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