# Musical tribute to math for Phi Day

-June 18, 2012

Three months and four days after Pi Day, we find ourselves on Phi Day, June 18.

Lesser known than Pi Day, Phi Day celebrates the golden ratio (two quantities are in the golden ratio if the ratio of the sum of the quantities to the larger quantity is equal to the ratio of the larger quantity to the smaller one), represented as 1.618 ... The reciprocal of this number is 0.618 … which in calendar notation equates to June 18.

Obviously, Phi is an important part of mathematics. But its influence is much more expansive than just one subject area.

The golden ratio is considered visually pleasing and can often be found represented in art and nature, like in the whorl of a nautilus shell. Greek sculptor Phidias is believed to have used the golden ratio when designing both the Parthenon and its great statue of Athena on the Acropolis in Athens.

Composers Bartok, Satie, and Debussy utilized the golden ratio in their music. And now, thanks to YouTube, we have visual evidence of Phi being celebrated in music. Check out this video in which Phi’s digits are translated into music as follows:

1 = C
2 = D
3 = E
4 = F
5 = G
6 = A
7 = B
8 = C octave
9 = D octave
0 = no note is played

And here’s a fun little web site devoted to the golden ratio, and here's a site all about Phi Day. May it and the video help you celebrate phi and all its golden glory!