Quantum theory is based heavily on probabilities, since measuring a quantum system doesn't produce the same outcome every time, but instead yields one of many outcomes that each occur with a certain ...

There is no measurement that can directly observe the wave function of a quantum mechanical system, but the wave function is still enormously useful as its (complex) square represents the probability ...

Physicists from the Canadian Institute for Measurement Standards are the first to measure a quantum mechanical wave function. And it only took 88 years from the formulation of Schroedinger’s equation!