bitter waters

In quantum mechanics, the state of a physical system is described by the so-called wave function (or the "wavefunction"). What is the wavefunction? All attempts by Schrödinger, who first introduced the wavefunction, and others to interpret it as a scalar potential of some physical field, or as the de Broglie wave (as in particle-wave dualism) were not successful. In 1926, Max Born noticed that the squared amplitude of the wavefunction of a particle in a given region gives the probability of finding the particle in this region. He suggested that the wavefunction represented not a physical reality but rather our knowledge of the quantum state of an object. The wavefunction represents our knowledge of all possible quantum-mechanical states of an object. In other words, the quantum-mechanical state of a physical system is a linear [...]