Math is supposed to be clean, simple, and beautiful. Most people would probably disagree with this statement, since some topics are overly complex for practically no reason. For instance, take a look at pi (π). It tells us a lot about circles, can be used to measure angles, and makes a tasty treat. If you’ve taken a geometry course, you might know that pi results when you divide a circle’s circumference by its diameter. But wait! Isn’t a circle supposed to be a set of points that are equidistant from a fixed center? The distance from the center of a circle to a point on its edge is called the radius. If the radius is so important in the definition of a circle, why don’t we divide the circumference by that instead of the diameter?

When the circumference of a circle is divided by its radius, we get a new number. This number is called tau. Simply put, tau is equal to two times pi. Now take a look at the formula for finding the circumference of a circle. Instead of 2πr, it’s just tau * r. Pretty easy, huh? Most other formulas follow suit, although the formula for finding the area of a circle is an exception; that one is a little bit ugly. What’s wrong with just using pi, you ask? Well, nothing is inherently wrong with it, but it’s unnecessarily more complicated and confusing.

If you’re not convinced that tau is a better number, take a look at this. Radians, a common method used to measure angles in trigonometry, are usually notated using pi. In this system, pi is a semicircle (180°) and 2pi is a full circle (360°). This makes things quite complicated to understand. You might instinctively think that 90° is one-fourth of pi. In actuality, one-fourth of pi is 45°, and 90° is one-half of pi. When using tau for radians, one tau is 360°. 90° is indeed one-fourth of tau, since it’s a full circle split into a fourth. 180° is one-half of tau. Radians are made incredibly easier to comprehend using this special number.

Overall, tau would be a great replacement to pi. Not only does it simplify mathematics, but it gives a clearer picture of concepts, such as radians. It has more applications in the worlds of trigonometry and calculus, but those won’t be covered here. If you are interested in seeing those applications, including other interesting content, see the link posted below. As a special mention, tau day is on June 28^th. Tell everyone you know to bake two pies!

Link: http://tauday.com/