Why in News?

• The golden ratio can be defined in terms of a line, divided into two unequal segments in a way that their lengths meet a simple condition.
• If we draw an arc across the top of the skull and divide it at a key junction over the brain, the two arc-segments are approximately in the golden ratio.
• The golden ratio is alternatively called the golden mean and the divine ratio. Its frequent appearances in nature have driven claims that it is the work of a divine design.
• This feature was studied recently by researchers of Johns Hopkins University, US, who have reported their findings in The Journal of Craniofacial Surgery.

How it makes the Ratio Golden?

• When the ratio between these two lengths (the longer segment divided by the shorter one) happens to be the same as the ratio between the entire line and the longer segment, then the line is said to be divided in the golden ratio (see illustration).
• For this condition to hold good, the ratio needs to be 1.61803… with the digits after the decimal going on forever; the golden ratio is what we call an “irrational number”.
• It is represented by the Greek letter phi.

Why such a ratio is Considered Special?

• Aesthetic appeal is among the first of many reasons.
• Architects such as Le Corbusier have consciously proportioned their works to the golden ratio, or close.
• So have artists such as Salvador Dalí and Leonardo da Vinci, whose fascination with the golden ratio features in the novel The Da Vinci Code and the film based on it.Interpretations of the golden ratio have not always been objective.

Other Examples:

• The fact remains, however, that the golden ratio frequently shows itself in nature, whether directly or indirectly (through its cousins called the Fibonacci numbers).
• To cite a few examples, the golden ratio appears in the seeds of sunflowers, the scales of pineapples, the arrangement of petals on a rose, DNA structures, the anatomy of the heart — and has now turned up in the human skull.