Many interactions are perfectly described by Schroedinger's equation. The interactions inside an atom, for example. Or the operation of a quantum computer. Wha

Many interactions are perfectly described by Schroedinger's equation. The interactions inside an atom, for example. Or the operation of a quantum computer. What "occurs" (that's the part we don't really understand) with probability defined by wave function is "measurement" but not every interaction is a measurement. A measurement is the macroscopic effect of interactions (which may or may not be fully described by Schroedinger's equation).