PMNS matrix (Pontecorvo-Maki-Nakagawa-Sakata matrix)

The PMNS matrix is a mathematical tool used in particle physics to describe how neutrinos, which are tiny, nearly massless particles, change types as they travel. Neutrinos come in three "flavors"—electron, muon, and tau—and the matrix explains how these flavors are mixtures of their underlying mass states. This mixing causes neutrinos to oscillate, or switch identities, over distance. The PMNS matrix consists of parameters that quantify the probabilities of these flavor changes, helping scientists understand neutrino behavior and fundamental properties of the universe.