Overgangsmatrixelement
Overgangsmatrixelement is a concept in quantum mechanics that describes the probability amplitude for a transition between two quantum states. It is a fundamental quantity used in calculating the rates of various physical processes, such as atomic excitations and de-excitations, particle scattering, and radioactive decay. Mathematically, it is represented as the matrix element of an operator corresponding to the interaction causing the transition, evaluated between the initial and final states of the system.
The magnitude of the overgangsmatrixelement is directly related to the likelihood of a particular transition occurring.