Marvel the minds of the ancient world as you discover the wonders of the golden ratio.

- The golden ratio is a mathematical term given to the phenomena of when two lengths, when divided via a formula, is equal to the number phi (φ).
- ‘Golden ratio’ is also known as ‘golden section’, ‘medial section’, ‘golden proportion’, ‘divine section’, ‘extreme and mean ratio’ and ‘golden mean’, and is called ‘sectio aurea’ in Latin.
- The formula of the golden ratio is the total of two lengths divided by the longer length (a+b/a), where it equals the longer length divided by the shorter length (a/b).
- A golden ratio occurs when the formula equation equals the number phi, which is roughly 1.618033, however, this number has an infinite number of decimal places.
- The golden ratio was likely first discovered by mathematicians of Ancient Greece, including Pythagoras and Euclid, and studied by later folk such as the Italian Leonardo Bonacci (Leonardo of Pisa).

###### Golden Ratio/Fibonacci Spiral evident in a Shell

Image courtesy of Jitz Couperos/Flick

- Many forms of nature feature the golden ratio in some arrangement, from human facial features, to the petals on flowers.
- Many artists, architects and musicians consider the golden ratio when creating their work; and the ratio is said to be evident in the Parthenon temple, and the Last Supper painting, among others.
- The Fibonacci sequence, described by Leonardo Banacci, that defines spirals evident in flowers, galaxy spirals, and hurricanes, uses the golden ratio.
- Rectangles can be created via the golden ratio, known as ‘golden rectangles’, that have sides of a 1:1.618 ratio, and they are widely accepted as being more aesthetically pleasing than rectangles of random sizes.
- The value of the golden ratio is not easily written as a fraction, as it is a continued fraction, and it is therefore usually written as a shortened decimal number, or as the symbol phi (φ).