The circle is one of the simplest forms and has been known since before the beginning of recorded history.
Circles are observed in nature. It is the basis for the wheel, a symbol for motion and progress. In mathematics, the study of the circle has helped inspire the development of geometry, astronomy and calculus. It can also be used to represent the lifecycle and the can be interpreted as the virtuous circle.
Because Pi's definition relates to the circle, it is found in many formulae in trigonometry and geometry. It is also found in other branches of science, such as cosmology, number theory, statistics, fractals, thermodynamic, mechanics and electromagnetism. The ubiquitous nature of Pi makes it one of the most widely known mathematical constants, both inside and outside the scientific community.
For thousands of years, mathematicians have been intrigued by Pi. Indian mathematicians – Madhava of Sangamagrama (13-14th century) and Srinivas Ramanujan (19-20th century) have contributed immensely in exploring Pi through their Mathematical analyses, number theory, infinite series, which has contribute greatly to modern mathematics. These mathematicians developed their own research in isolation while the world noticed and reconised the developments in Europe.
Pi shifts our attention from the linear to the circular just as sustainability tries to shift our thinking from considering things as a straight path forward to a closed-loop system – The Circle.
The first evidence of Pi dates back to 1900 BC. It has been 4000 years hence and it has not yet been completely figured out. We are still trying to get more accurate in its calculation with the 10 trillionth digit calculated. Sustainability as a concept is similar which does not seem to have an end destination, but only increasing levels of complexity, improvement and accuracy in how we practice it. Sustainability is a mix of interconnected ideas that practitioners strive to describe and refine. In the end, you can only make these relationships more and more precise all you want. Pi and Sustainability remain an expression about the relationship between things; their relevance and benefit comes from applying them.