Pi Day is celebrated annually on March 14, representing the first three digits of the mathematical constant pi (approximately 3.14159). Pi defines the ratio of a circle's circumference to its diameter and has infinite digits. Its applications are extensive and fundamental across various scientific and engineering fields.
Origin of Pi Day
Pi Day was established in 1988 by Larry Shaw, a physicist at the Exploratorium science museum in San Francisco. Shaw aimed to engage the public in mathematical learning. The initial celebration involved staff and later evolved into a public procession where attendees carried digits of pi. The main celebration at the museum commences at 1:59 p.m., referencing the next three digits of pi.
Applications of Pi in Science
Space Exploration
Artur Davoyan, a professor of mechanical and aerospace engineering at UCLA, states that pi is integral to almost every formula used in spacecraft motion, material science, and propulsion systems.
Any object with a round or cyclical nature, such as radio waves, involves pi.
Even irregular shapes can be analyzed using pi by breaking them down into smaller circles. Davoyan's research focuses on developing new propulsion systems for faster spacecraft travel. NASA utilizes pi to calculate Earth's orbital position for communication with probes like Voyager 1 and 2 and to process incoming signals. Complex signals, even from unknown sources, are often broken down into functions that inherently involve pi.
Fluid Dynamics and Bioengineering
Dino Di Carlo, chair of the bioengineering department at the UCLA Samueli School of Engineering, extensively uses pi in studying small fluid volumes.
His research involves creating polymer particles that function as miniature test tubes for cells, aiding in the examination of cell functions.
Pi is crucial for calculating the formation of these droplets, surface tension, and controlling droplet size. Di Carlo applies this technique to identify antibodies that can inhibit cancer cell signals. Pi is also vital in calculations for fluid flow through tubes and barriers, as seen in at-home COVID-19 tests. Di Carlo leveraged these principles to develop a 20-minute Lyme disease test, significantly reducing diagnosis time from days or weeks.