What is the number pi and why is it so important?

Question: What do Archimedes, Euler and Isaac Newton have in common?

Answer: First, they were all famous mathematicians. Archimedes discovered the law of hydrostatics; Euler is, to date, considered the most successful mathematician of all time; and Newton formulated the law of gravitation.

Second, they all spent considerable time working on the mathematical constant known as "pi." But what makes the pi so important for these and several other bright minds that they'd spend so much of their time focusing on it? Before we answer this question we have to first cover the basics.

What is the pi?

Simply put, pi is the ratio of a circle’s circumference to its diameter, and this ratio is approximately 3.14. So it's no coincidence that the mathematics, science and engineering worlds celebrate Pi Day every year on March 14 (3/14).

Pi is a constant, stays the same no matter how large or small the circle is and it is represented by the Greek letter π. 

Here is an interesting fact about the pi: Pi has infinite decimals that are randomly distributed. If you were to look at all the decimals of the pi, you will find your birthday (month | day | year) somewhere within the string of numbers. In fact, you can use this tool to find out where your birthday falls within the pi.  

Now that the basics are covered, let’s dive into why so many bright minds across the history spent their time studying pi number. 

Why the pi is so important? 

Well, our lives would be a little different without the pi. Practically most things we use in our everyday lives leverage the pi in their designs or in the way they operate. Let's skip the most obvious ones such as tires, pipes at your home or the cup that holds your morning coffee, and focus on some of the lesser known yet indispensable uses of pi in our lives. 

• Space exploration: From ancient Egyptians to modern scientists at NASA, humankind always had the utmost desire to explore space. Whether it was Sputnik becoming the first artificial satellite in space, or the Apollo 11 spaceflight doing the first lunar landing, pi has always been there. Today, NASA commonly uses pi to drive Mars rovers, discover potentially habitable worlds and investigating alien ice and beyond. 
• Your daily entertainment: Streaming your favorite shows, talking to your friends and ordering food online, all depend on electromagnetic waves for wireless communication. Pi is used in calculating the wavelengths of these communications. 
• Keeping your life Always On: Energy is one of most essential ingredients of our lives. We use electrical energy to keep our lights on, have smart devices connected and to power our everyday activities. Power generators are often used to generate this electricity keeping us Always On. Pi is used in many places in power generators from the calculation of engine displacements to the estimation of the fuel droplet size within the combustion system. 

A world without pi would have been very different, but thanks to all the bright minds humankind had, we don’t need to speculate that world and instead enjoy the world as we know it.

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