Phi - The Divine Number

Last year I read "Da Vinci Code" by Dan Brown . The best thing I liked about the book was the captivating way he defined the Phi ..(Fibonacci Series..) also known as divine proportion ...This is not Dan Brown's description but gives some good information about phi and why it is called divine proportion..or golden number...

What is Phi?

Also known as the golden number, it the basis for the 'Golden Ratio'. This is a mathematical proportion that appears repeatedly in nature and has long been considered a especially pleasing to the eye. Look at a pine cone or a nautilus shell and you will see an obvious representation of Phi.

Phi Diagrammed

With a geometric overlay, it is easy to see how the shape of a nautilus shell conforms to the Golden Ratio. The ratio of each segment's size to that of the previous segment is roughly 1.6, which is approximately equal to Phi.(See Image above)

By the Numbers

Phi is approximated as 1.618 but is actuality a 'non-terminating decimal,' meaning that it is a never-ending number. A mathmetical definition of Phi is that Phi squared equals Phi plus one. There is only one other number that has that property. Phi has been calculated with extraordinary accuracy

Why is it Called Phi?

The symbol φ or "phi" (pronounced "fee") was first used at the beginning of the 20th century. It is the first Greek letter in the name of Greek sculptor Phidias who lived around 490 - 430 B.C. Phidias used the Golden Ratio in some of his most famous sculptures including this statue of Zeus in the temple of Olympia.

Who Figured it Out?

The first definition of the golden ratio was provided around 300 B.C. by Euclid, the founder of geometry. He explained the perfect proportion of a line cut into its "extreme and mean ratio." That line (A--------------C-------B) is proportioned such that the ratio of the length of AC to that of CB equals the ratio of AB to AC.

The Significance?

Phi and the golden ratio pop up everywhere. Humans seem to find it particularly appealing. You can find it in architecture (the Guggenheim Museum), in music (some say Stradivarius used it to construct his famous violins), in nature (flowers, ferns and more) and in art such as the Last Supper.

For more information check out the following websites:
http://goldennumber.net/classic/heartbeat.htm

Courtsey: http://reference.aol.com/movies/da-vinci-code/phi