The Nishina formula is a mathematical expression used in physics to describe the scattering of photons, particularly in the context of Compton scattering. It provides a way to calculate the differential cross-section, which quantifies how likely photons are to scatter at different angles when they interact with electrons. Developed by Yoshio Nishina in the early 20th century, the formula incorporates the principles of quantum mechanics and relativity. It is significant in fields such as particle physics and astrophysics, helping scientists understand the behavior of high-energy photons in various environments, including cosmic rays and radiation processes.