This is a practical method used in applied mathematics, physics and engineering.

Let me start by stating that this article will be quite technical (unlike the other articles), and might be challenging for the lay public. Anyway, I invite you to read and ask questions in the comments if something is unclear.

The Buckingham π theorem can be used to find the “hidden” relation between physical quantities that describe a certain phenomenon. It relies on the principle of dimensional homogeneity which basically tell us that we can’t sum apples with melons.

I introduce this theorem here by means of an example. Let’s consider a pendulum, and suppose that we want to find movement’s period. So, we want to find an equation that tell us how the period depends on the physical quantities that affect the period.