**By Robin Prokaski**

As many mathematicians know, Pi is
the ratio between a circle’s circumference and diameter. Many of us know that
Pi can be approximated at 3.14. However, it is a never ending number. As of
2013, Pi has been calculated to 12.1 trillion digits (The Math Mystery). Even
though Pi is such an integral part of many aspects of mathematics, few truly
know the early history of Pi. Furthermore, rarely people understand that it
comes from nature, and how abundant in nature it really is.

To
start off lets first talk about the history of Pi. To this day, we do not know
the first to become conscious of this ratio. However, we seem to think human
civilizations could have been aware of this as early as 2550 BC. The great
Egyptian pyramids were built between 2550 BC and 2500 BC. It turns out that the
height and the width come out to approximately 2 times pi. These were measured
in cubits, were approximately 18 inches. However, a cubit was measured by the
length of a person’s forearm. Therefore, it varied from one person to another.
Early texts reveals the Egyptians found an approximation for pi to be 3.16
(Purewal 2013).

One
of the biggest contributors to the development of Pi was Archimedes. He is
considered to be the first person to calculate an accurate approximation of Pi.
He did this by using area of two Polygons. One of these polygons inscribed the
circle, while the other was inscribed by the circle. Essentially, he kept
increasing the number of sides of the polygons and effectively got closer and
closer to the area of the circle. He continued this process until reaching
polygons with 96 sides. This process allowed him to get an approximation
between 3.1408 and 3.1429 (Smoller 2001).

One
of the text that contains an approximation of Pi that is not as frequently
talked about is the Bible. The following verse contains an approximation for
Pi: “"And he made a molten sea, ten cubits from the one brim to the other:
it was round all about, and his height was five cubits: and a line of thirty cubits
did compass it round about"(1 Kings 7:23). From this quote, one would
think that their approximation was 3:1. However, cubits were the unit of
measurement. As mentioned previously, cubits change from person to person, and
the approximation could really have been more accurate than it seems (Purewal
2013). From here, many different
mathematicians made contributions for Pi. Now let’s focus on topic that many
people are not that familiar with, Pi in nature.

Pi
is often thought of just the ratio between circumference and diameter of a
circle. In the Documentary “The Mystery of Math” a
professor explains the following example: If a sheet of paper is divided into
any amount of sections in which r is the length between lines, and a needle, of
length r, is dropped onto the paper, the probability that the needle cuts
across a line is 2/Pi. Even though there is no circles or diameters of circles,
Pi still comes into play. Experts say that Pi is able to show up in the
strangest of places because it is one of only concepts to relate a straight
object (diameter) with a rounded one (circle). One of the places that comes
into play is the path of rivers. As we know, a river is rarely ever straight,
but is not circular either. On average, the actual length of the river over the
direct distance from start to finish is about Pi. Similar to rivers, any models
that deal with waves has Pi in them. Most commonly, these are light and sound
waves. The documentary mentioned earlier also explains that Pi tells us which
color should appear in a rainbow, and how middle C should sound like on a
piano. On the biology side of things, Pi explains how cells grow into spherical
shapes such as oranges or apples (Mystery of Math).

However, Pi is found in many other different aspects of nature. One
area that many people do not realize pi is involved in is probability.
Pi
is part of a hidden interconnected web that relates many different aspects of
our world. It is our job as mathematicians to find these hidden connections, to
better understand our world and nature.

**References**

The Math Mystery: Mathematics in
Nature and Universe - Documentary. (2015, June 11). Retrieved

November 24, 2015,
from https://www.youtube.com/watch?v=8gd-gUlBv_s

Purewal, S. (2010, March 13). A brief history of
pi. Retrieved November 11, 15, from

http://www.pcworld.com/article/191389/a-brief-history-of-pi.html

Smoller, L. (2001, February). The
amazing history of pi. Retrieved November 24, 15, from

http://www.ualr.edu/lasmoller/pi.html